Russian Federation

"TECHNICAL SULFUR. TEST METHODS. GOST 127.2-93" (approved by the State Standard of the USSR of 10.21.93, protocol N 4-93)

Introduction date 1997-01-01

1 DEVELOPED by the Research and Design Institute of the Sulfur Industry with a Pilot Plant, Ukraine

INTRODUCED by the Technical Secretariat of the Interstate Council for Standardization, Metrology and Certification

2 ADOPTED by the Interstate Council for Standardization, Metrology and Certification on October 21, 1993 (order N 1 to protocol N 4-93)

State name	Name of the national standardization body
Republic of Armenia	Armstate standard
Republic of Belarus	Belstandard
The Republic of Kazakhstan	State Standard of the Republic of Kazakhstan
The Republic of Moldova	Moldovastandard
Russian Federation	Gosstandart of Russia
Turkmenistan	Turkmenglavstate inspection
The Republic of Uzbekistan	Uzgosstandart
Ukraine	State Standard of Ukraine

3 Resolution of the Committee Russian Federation on standardization, metrology and certification dated March 21, 1996 N 199, the interstate standard GOST 127.2-93 was put into effect directly as state standard since January 1, 1997

4 INSTEAD OF GOST 127-76 (in terms of analysis methods)

This standard applies to technical sulfur liquid, lump and ground and establishes methods for testing its physical and chemical properties.

REFERENCE REGULATIONS AND TECHNICAL DOCUMENTS

	Number of paragraph, subparagraph	The designation of the NTD to which the link is given	Number of paragraph, subparagraph
GOST 127.3-93	1.8	GOST 5789-78	7.1.2
GOST 435-77	9.1.2	GOST 5841-74	6.3.2; 7.2.2
GOST 1027-67	6.1.2; 10.1.2	GOST 5848-73	7.1.2
GOST 1625-89	9.1.2	GOST 5955-75	5.2.2
GOST 1770-74	4.2; 5.4.2; 6.1.2; 6.3.2;	GOST 6613-86	5.2.2; 6.2.2; 13.2
	7.1.2; 7.2.2; 8.2;	GOST 6552-80	9.2.2
	9.1.2; 9.2.2; 10.1.2;	GOST 6709-72	1.4
	10.2.2	GOST 7172-76	6.3.2
GOST 1973-77	6.1.2; 6.3.2	GOST 7328-82	1.4
GOST 2053 77	5.4.2	GOST 7995-80	5.1.2
GOST 2603 79	5.2.2	GOST 8864-71	10.1.2; 10.2.2
GOST 3118-77	6.1.2	GOST 9147-80	5.1.2:5.4.2; 6.3.2
GOST 3760-79	7.1.2; 10.1.2; 10.2.2	GOST 10485-75	6.1.2
GOST 3765-78	6.3.2	GOST 10652-73	7.1.2; 10.2.2
GOST 3773-72	7.1.2	GOST 12026-76	4.2; 5 4 2- 6.3.2;
GOST 3776-78	5.1.2		10.2.2
GOST 4109-79	6.1.2; 7.2.2	GOST 13045-81	5.1.2
GOST 4165-78	10.1.2	GOST 13647-78	6.1.2
GOST 4166-76	5.1.2	GOST 14919-83	3.2; 5.4.2; 6.1.2;
GOST 4171-76	5.1.2		6.3.2: 8.2; 9.1.2;
GOST 4204-77	5.1.2; 6.1.2; 6.3.2;		9.2.2
	7.1.2; 7.2.2; 8.2;	GOST 16539-79	5.1.2; 11.2
	9.1.2; 9.2.2; 10.1.2;	GOST 18300-87	4.2; 5.4.2; 6.2.2;
	10.2.2		6.3.2; 11.2
GOST 4212-76	1 6-6 1 2; 7 1 2- 7 2.2	GOST 19908-90	3.2; 5.3.2; 6.3.2; 8.2
GOST 4232-74	6.1.2	GOST 20288-74	5.4.2; 6.1.2; 7.2.2;
GOST 4328-77	4.2		10.1.2
GOST 4461-77	6.1.2; 6.3.2; 7.2.2;	GOST 20490-75	5.1.2; 9.2.2
	8.2; 9.2.2; 10.2.2	GOST 22280-76	8.2
GOST 4470-79	11.2	GOST 24104-88	1.4
GOST 4517-87	1.6; 4.2; 6.1.2	GOST 24363-80	4.2; 5.1.2
GOST 4530-76	5.1.2	GOST 25336-82	3.2; 4.2; 5.1.2; 5.2.2;
GOST 4919.1-77	1.6		5.3.2; 5.4.2; 6.1.2;
GOST 4919.2-77	1.6		6.2.2; 6.3.2; 7.1.2;
GOST 5456-79	8.2; 9.1.2		7.2.2; 9.2.2; 10.1.2;
GOST 5556-81	5.1.2; 7.1.2; 9.1.2;		10.2.2; 12.2; 13.2
	10.1.2	GOST 25794.1-83	1.6

1.1 The limits of application of the methods are indicated in Table 1.

Table 1

	Defined indicator	Analysis method	Limits of application of the method, mass fraction of the element. %	Section, paragraph of the standard containing the method of analysis
1	Sulfur	Estimated	-	2
2	Ash	weight	0.007 to 0.4	3
3	acids	Titrimetric	More than 0.001	4
4	organic matter	gas volumetric	More than 0.005	5.1
	organic matter	Spectral		5.2
		weight		5.3
		extraction	-"-	5.4
5	Arsenic	Photometric using silver diethyldithiocarbamate	0.00005 to 0.005	6.1
		Spectral	0.0001 to 1.0	6.2
		Photometric using molybdenum blue	0.005 to 0.1	6.3
6	Selenium	Photometric using 3.3"-diaminobenzidine	0.0005 to 0.04	7.1
		Photometric using hydrazine sulfate	-"-	7.2
7	Iron	Photometric using O-phenanthroline	0.002 to 0.2	8
		Spectral	0.001 to 1	11
8	Manganese	Photometric with formaldehyde oxime	0.0005 to 0.002	9.1
		Photometric using potassium iodate	-"-	9.2
		Spectral	0.001 to 1	11
9	Copper	Photometric using lead diethyldithiocarbamate	0.0005 to 0.001	10.1
		Photometric using sodium diethyldithiocarbamate	0.0002 to 0.002	10.2
		Spectral	0.001 to 1	11
10	Water	weight	More than 0.001	12
11	Grading	weight	0.001 to 0.01	13

1.2 The established confidence level (P), with which the determination error is within the limits specified in the methods of analysis, is 0.95.

1.3 The results of analyzes are rounded up to significant figures in accordance with the norms established by the standards for the corresponding type of sulfur.

1.4 When conducting analyzes and preparing reagent solutions, unless otherwise indicated, the following is used:

Reagents of qualification not lower than pure for analysis (analytical grade);

General purpose laboratory scales of the 2nd accuracy class according to GOST 24104 with the highest limit weighing 200 g;

A set of general-purpose weights of the 2nd accuracy class according to GOST 7328, weighing 210 g.

1.5 It is allowed to use for quality control any methods, measuring instruments and equipment that have passed metrological certification and having accuracy characteristics not lower than those given in this standard. In case of disagreement in the assessment of quality, the determination is carried out using the methods of this standard.

1.6 Preparation of solutions and reagents is carried out according to GOST 4212, GOST 4517, GOST 4919.1, GOST 4919.2, GOST 25794.1.

1.7 Calibration graphs are built once every three months and after each change of reagents.

When constructing calibration graphs, each point should be the arithmetic mean of the results of three parallel measurements.

1.8 Sampling and preparation according to GOST 127.3.

The mass fraction of sulfur in terms of dry matter X1, %, is calculated by the formula

X1 = 100 - (X2 + X3 + X5),

(1)

Where X2 is the mass fraction of ash, determined according to Sec. 3,%;

X3 - mass fraction of acids in terms of sulfuric acid, determined according to Sec. four, %;

X5 - mass fraction organic matter, determined according to Sec. 5, %.

3.1 Essence of the method

The method is based on the weight determination of the mass of the residue after calcination of the sample at a temperature of (800 ± 10) °C.

3.2 Apparatus:

Electric resistance furnace laboratory type SNOL, providing a stable heating temperature (800±10) °C;

Desiccator 2-230 according to GOST 25336;

Bowl 50 (80) or crucible H-50 (80) according to GOST 19908;

Single-burner electric stove according to GOST 14919.

3.3 Conducting an analysis

(20.0±0.1) g of the sample is placed in a bowl, previously calcined and brought to constant weight. The bowl is placed on an electric stove, the sulfur is slightly melted and set on fire. The heating temperature is maintained at about 220 ° C, so that the sulfur burns slowly for 30 minutes until the sulfur is completely burned. Then the bowl is placed in an electric furnace, calcined at a temperature of (800 ± 10) ° C to constant weight, cooled in a desiccator and weighed. The results of all weighings in grams are recorded to the third decimal place.

If the mass fraction of ash in sulfur is less than 0.02%, it is allowed to increase the sample up to 50.0 g.

3.4 Handling results

The mass fraction of ash X2,%, is calculated by the formula

(2)

Where m1 is the mass of the residue after calcination in an electric furnace, g;

m is the mass of the analyzed sample, g.

The result of the analysis is taken as the arithmetic mean of the results of two parallel determinations, the absolute allowable discrepancy between which, as well as the absolute total error of the analysis results, do not exceed the values indicated in Table 2.

table 2

In percents

Mass fraction of ash	Permissible discrepancy	Total error
From 0.007 to 0.030 inclusive	0,004	0,002
St. 0.030 to 0.070 - "-	0,010	0,006
-"- 0.07 to 0.10 -"-	0,02	0,01
-"- 0.10 to 0.30 -"-	0,03	0,01
-"- 0.30 to 0.40 -"-	0,07	0,03

4.1 Essence of the method

The method is based on the extraction of acidic substances with water and titration of the resulting extract with sodium hydroxide or potassium hydroxide in the presence of phenolphthalein.

4.2 Apparatus, reagents and solutions:

Pipette with a capacity of 100 cm3;

Burettes with a capacity of 5 and 10 cm3;

Beaker 250 according to GOST 1770;

Cylinder 1-25 according to GOST 1770;

Glass B-1-400 TC according to GOST 25336;

Flask Kn-2-250-34 XC according to GOST 25336;

Laboratory filter paper according to GOST 12026;

Ethyl alcohol technical according to GOST 18300;

Phenolphthalein (indicator), alcohol solution with mass fraction th 1%;

Potassium hydroxide according to GOST 24363 or sodium hydroxide according to GOST 4328, concentration solution with (KOH, NaOH) = 0.01 mol/dm3 (0.01n.);

Distilled water, not containing CO2; prepared according to GOST 4517.

4.3 Conducting the analysis

(50 ± 1) g of sulfur are weighed, recording the weighing result in grams to the nearest three decimal places, placed in a beaker, moistened with 25 cm3 of ethanol and 200 cm3 of water are added. The contents of the glass are stirred, the glass is covered with a watch glass and boiled for 15-20 minutes, stirring occasionally. After cooling, the contents of the beaker are filtered through a folded paper filter into a volumetric flask, the volume of the solution is adjusted to the mark with water that does not contain CO2, and mixed thoroughly. 100 cm3 of the filtrate are taken into a conical flask, titrated from a burette with a solution of potassium or sodium hydroxide in the presence of phenolphthalein until a light pink color does not disappear within 1 minute. It is allowed to carry out titration using a potentiometer, taking pH = 8.2-8.3 as the equivalence point (end of titration).

At the same time, a control experiment is carried out with a solution containing water and alcohol under the same conditions and with the same amount of reagents, but without the analyzed product.

4.4 Handling results

The mass fraction of acids in terms of sulfuric acid X3,%, is calculated by the formula

(3)

Where V1 is the volume of sodium or potassium hydroxide solution used for titration of the analyzed solution, cm3;

V2 is the volume of sodium or potassium hydroxide solution used for titration of the control sample solution, cm3;

0.00049 is the mass of sulfuric acid corresponding to 1 cm3 of sodium or potassium hydroxide solution with a concentration of exactly 0.01 mol/dm3, g;

m is the weight of the sample of sulfur, g;

K is a correction factor to bring the concentration of sodium or potassium hydroxide solution to exactly 0.01 mol/dm3.

The arithmetic mean of the results of two parallel determinations is taken as the result of the analysis, the absolute permissible value of the discrepancies between which, as well as the absolute values of the total error of the result of the analysis, do not exceed the values indicated in Table 3.

Table 3

In percents

8.1 Essence of the method

The method is based on the photometric measurement of the optical density of the red complex of iron (II) with o-phenanthroline at pH 3-4.

8.2 Apparatus, reagents and solutions:

SF-type spectrophotometer with a visible radiation limit and cuvettes with a thickness of a light-absorbing layer with a solution of 1 and 2 cm;

Laboratory resistance electric furnace of the SNOL type, providing a stable heating temperature (500 ± 10) °С;

Single-burner electric stove according to GOST 14919;

Cylinder 1-10 according to GOST 1770;

Flasks 2-50-2, 2-100-2, 2-500-2, 2-1000-2 according to GOST 1770;

Pipettes with a capacity of 5, 10, 20, 25 and 50 cm3;

Crucible H-20 according to GOST 19908;

Nitric acid according to GOST 4461, chemically pure, diluted 1:1;

Sulfuric acid according to GOST 4204, chemically pure diluted 1:2;

Hydroxylamine hydrochloric acid according to GOST 5456, solution with a mass fraction of 10%;

Sodium citrate according to GOST 22280, solution with a mass fraction of 25% and pH 3-5;

O-phenanthroline, h., solution with a mass fraction of 0.25%, obtained by dissolving in hot water (freshly prepared);

Iron-ammonium alum, chemically pure;

The main solution with a mass concentration of iron of 0.1 mg/cm3 is prepared as follows: 0.8635 g of iron ammonium alum is dissolved in water with the addition of 4 cm3 of concentrated sulfuric acid and topped up with water in a volumetric flask with a capacity of 1 dm3 to the mark, working solution with a mass concentration of iron 0.01 mg/cm3 is prepared by 10-fold dilution of the stock solution with water.

8.3 Preparing for analysis

To build a calibration graph, 0; 2.5; 5; ten; 12.5; fifteen; twenty; 25 and 30 cm3 of a working solution containing, respectively, 0.000; 0.025; 0.050, 0.100, 0.125; 0.200; 0.250 and 0.300 mg of iron, diluted with water to 20 cm3, add 1 cm3 of hydroxylamine hydrochloride solution, hold for 5 minutes, then add 5 cm3 of o-phenanthroline solution, 2 cm3 of sodium citrate solution, add water to the mark and mix. After 15 minutes, the optical density of the solutions is measured with respect to water at a wavelength of 500 nm, in a cuvette with a thickness of the solution absorbing light layer of 1 cm.

Based on the data obtained, a calibration graph is built, plotting the mass of iron in milligrams on the abscissa axis, and the corresponding optical density value on the ordinate axis.

8.4 Conducting analysis

(20 ± 1) g of sulfur is weighed, recording the weighing result in grams to the fourth decimal place, placed in a quartz crucible, carefully burned and the residue is calcined at (500 ± 10) ° C for 15-20 minutes.

After cooling, the residue in the crucible is poured with 10 cm3 of nitric acid solution, heated for about 10 minutes, 2 cm3 of sulfuric acid solution are carefully added and evaporated until white fumes appear.

Then cool and add 20 cm3 of water. The resulting solution is filtered and transferred quantitatively to a 100 cm3 volumetric flask. The solution is used to determine the mass fraction of manganese and copper.

5 cm3 of an aliquot of the solution is taken with a pipette, placed in a volumetric flask with a capacity of 50 cm3, diluted with water to 20 cm3, 1 cm3 of hydroxylamine hydrochloride solution is added, incubated for 5 minutes, then 5 cm3 of o-phenanthroline solution, 2 cm3 of sodium citrate solution are added, topped up with water to the mark, mix and after 15 min measure the optical density of the analyzed solution according to 8.3.

The reference solution is a solution prepared under the same conditions and with the same amount of reagents, but without the analyzed product.

The mass of iron in the analyzed solution in milligrams is found according to the calibration curve.

8.5 Handling results

The mass fraction of iron X8,%, is calculated by the formula

(13)

Where m1 is the mass of iron found from the calibration curve, mg;

m is the weight of the sample of sulfur, g;

V is the volume of the solution selected for analysis, cm3.

The result of the analysis is taken as the arithmetic mean of the results of two parallel determinations, the relative discrepancy between which does not exceed the allowable discrepancy of 20%.

Agate or chalcedony mortars, 90 mm in diameter;

Spectrographic photographic plates of the "micro" type with a sensitivity of 90 units;

Infrared lamp;

Electrodes coal brand OS. part 7-4 or C-1; lower electrode with a crater 4 mm in diameter, 4 mm deep; the upper electrode is sharpened on a truncated cone with a platform of 2 mm;

iron oxide;

Copper (II) oxide according to GOST 16539;

Manganese (IV) oxide according to GOST 4470;

Sulfur os. ch. 16-5;

Developer and fixer;

Ethyl alcohol technical according to GOST 18300, distilled.

11.3 Preparing for analysis

The main sample of sulfur with a mass fraction of iron, manganese and copper, 10% of each element, is prepared as follows: 6.027 g of sulfur of special purity. mixed with 1.429 g of iron oxide, 1.253 g of copper oxide and 1.291 g of manganese oxide. The mixture is ground in an agate mortar under a layer of alcohol for 1.5-2 hours, then dried under an infrared lamp at (80 ± 2) ° C to constant weight.

Reference samples are prepared from the main sample by successive dilution of pure sulfur. Mass fraction of iron, manganese and copper in samples, %:

The first comparison sample - 1;

the second sample of comparison - 0.3;

the third comparison sample - 0.1 each;

the fourth comparison sample - 0.03 each;

the fifth comparison sample - 0.01 each;

the sixth comparison sample - 0.003 each;

the seventh comparison sample - 0.001 each.

Comparison samples, like the main sample, are prepared in an agate mortar under a layer of alcohol. Samples are stored in plastic containers with ground stoppers.

Reference samples are introduced into the hole of the lower electrode using a dosing plate made of organic glass.

A low-voltage spark is ignited between the electrodes from a DG-2 generator with a current of 6 A, the distance between the electrodes is 2 mm, the exposure is 25 s.

The spectra of reference samples are photographed three times with a spectrograph at a slit width of 0.01 mm.

On the obtained spectrograms, the blackening of the analytical lines and the background near the analytical lines is measured according to table 5.

Table 5

Based on the results of photometry of the spectra of comparison samples, calibration graphs are built in the coordinates - mass fraction (of iron, manganese and copper) - blackening of analytical lines.

11.4 Conducting analysis

The analyzed sulfur sample is crushed under alcohol to the same size as the reference samples, and the blackening of the analytical lines is measured according to 11.3.

According to the results of photometry of the spectra according to the calibration curve, the mass fraction of iron, manganese and copper in the analyzed sample is found.

The result of the analysis is taken as the arithmetic mean of the results of two parallel determinations, the relative allowable discrepancy between which should not exceed the allowable discrepancy equal to 30% of the average value.

Limits of permissible relative total error of the analysis result ± 15%.

The reproducibility of the spectral method for determining the mass fraction of iron, manganese and copper in sulfur is characterized by the mean square error of ± 15%.

12.1 Essence of the method

The method is based on weight determination of weight loss due to drying at (70 ± 2)°C.

12.2 Apparatus:

A cup of ChBN-2 according to GOST 25336.

12.3 Conducting analysis

(100 ± 1) g of lump sulfur and (10 ± 1) g of ground sulfur are weighed in cups dried to constant weight, dried in an oven at a temperature of (70 ± 2) ° C to constant weight and weighed.

Up to 0.80 incl.0,1 0,05 St. 0.800,02 0,01

13.1 Essence of the method

The method is based on the weight determination of the content of fractions obtained by sieving the sample on sieves.

13.2. Equipment and reagents:

Sieves with a shell with a diameter of 75 mm, a height of 45 mm, mesh 014 H and 0071 H according to GOST 6613;

Flute brush (N 18 from horsehair);

Drying cabinet type SNOL, providing a stable heating temperature (70 ± 2) ° С;

Cup CH according to GOST 25336;

Cup ChKTs in accordance with GOST 25336.

13.3 Testing

(20 ± 1) g of ground sulfur dried at (20 ± 2) ° C is transferred to a sieve with a 014 N mesh, a sieve with a 0071 H mesh is placed under it, and then a tray and sieving is carried out for 20 minutes. Then open the lid, crush the lumps of sulfur on the sieves with a soft brush and remove the sulfur from the back of the sieve into the next sieve or tray. Sieving is repeated until the residue on the sieves ceases to decrease.

Note - In the absence of an apparatus for mechanical sieving, sieving is carried out manually on the same sieves, wiping the sulfur on the sieve with a brush.

At the end of the sieving, the residue is transferred with a brush into a weighed cup and weighed.

The results of all weighings in grams are recorded to the third decimal place.

13.4 Handling results

The residue on the X12 sieve, %, is calculated by the formula

(19)

Where m is the weight of the sample of sulfur, g;

m1 - mass of residue on the sieve, g.

The result of the analysis is taken as the arithmetic mean of the results of two parallel determinations, the relative discrepancy between which does not exceed the allowable discrepancy equal to 10% of the average value.

Limits of permissible relative total error of the analysis result ± 7%.

GOST 127.5-93

INTERSTATE STANDARD

SULFUR GROUND
FOR AGRICULTURE

TECHNICAL CONDITIONS

INTERSTATE COUNCIL
ON STANDARDIZATION, METROLOGY AND CERTIFICATION

Minsk

Foreword

Technicalterms

Ground sulfur for agriculture. Specifications

Introduction date 1997-01-01

This standard applies to ground sulfur for Agriculture obtained by grinding technical sulfur.

Ground sulfur for agriculture is used as an acarofunsicide to control powdery mildew and mites on all crops, except for gooseberries, for the preparation of sulfur formulations and mixed preparations, as well as for export.

The requirements of this standard are mandatory.

1 TECHNICAL REQUIREMENTS

2 SAFETY REQUIREMENTS

2.1 Sulfur is flammable.

Sulfur dust suspended in the air is fire and explosion hazard: the lower concentration limit of flame propagation (ignition) is 17 g / m 3, the autoignition temperature is 190° C according to GOST 12.1.041.

When sulfur burns, sulfur dioxide is formed.

Sulfur belongs to the 4th hazard class (GOST 12.1.005).

The maximum permissible mass concentration in the air of the working area: sulfur - 6 mg/m 3 ; sulfur dioxide - 10 mg / m 3. Sulfur does not form additional toxic compounds in the air and sewage in the presence of other substances and does not have cumulative properties.

2.2 All work with sulfur is carried out in accordance with GOST 12.3.041.

2.3 Production facilities and laboratories where sulfur is handled must be equipped with supply and exhaust mechanical ventilation that ensures compliance with the maximum permissible concentrations of harmful substances in the air of the working area.

2.4 All employees must be provided special clothing and personal protective equipment:

Dressing gowns or overalls made of moleskin dustproof fabric according to GOST 21790;

Mittens "KR" cotton with a film coating in accordance with GOST 12.4.020;

safety shoes;

Anti-dust glasses according to GOST 12.4.013;

Respirators of the "Petal" type.

2.5 When sulfur dust enters the human body, inflammation of the mucous membranes of the eyes and upper respiratory tract, irritation of the skin, and a disease of the gastrointestinal tract are possible.

2.6 If sulfur gets inside, it is necessary to drink several glasses of warm water or a weak solution of potassium permanganate and induce vomiting by mechanical irritation of the pharynx.

After that, drink 0.5 glass of water with 2 - 3 activated charcoal tablets, and then rinse your mouth with water.

If sulfur gets on the skin, wash thoroughly with soap and water. If sulfur gets into the eyes, rinse them with plenty of water, a 2% solution of baking soda or boric acid. In case of poisoning through the respiratory tract - immediately remove the victim from the sulfur zone, change contaminated clothing, rinse the mouth with warm water.

In all cases of sulfur poisoning, you should consult a doctor.

There should be a first aid kit in places where sulfur is handled.

2.7 After working with sulfur, you need to take a shower, change clothes and underwear.

2.8 Disposal of overalls and containers must be carried out in places specially designated for this purpose, no closer than 200 m from housing and industrial buildings. Paper bags must be burned. Thoroughly shake out overalls after finishing work with sulfur.

Overalls are washed in a hot soapy-soda solution containing 0.5% soda and 2.5% soap, at least after 8 working shifts.

Cleaning of premises and equipment is carried out in a dry way using a vacuum system.

2.9 While working with sulfur, it is strictly forbidden to smoke and use open fire. In case of ignition, extinguish with sand, asbestos cloth or water jet.

3 ACCEPTANCE RULES

3.1 Sulfur is accepted in batches. A batch is considered to be the amount of sulfur with a volume of not more than one transport unit (wagon, car), accompanied by one quality document.

3.2 The quality document must contain:

Name of the manufacturer and (or) its trademark;

Product name;

Batch number and date of manufacture;

The results of the analyzes carried out or confirmation of the product's compliance with the requirements of this standard;

Net weight;

The designation of this standard;

Signature and stamp of the technical control service.

3.3 Sulfur is subjected to acceptance tests.

3.4 For quality control, at least 1% of sulfur packaging units are selected, but at least five bags or two containers.

3.5 Upon receipt of unsatisfactory results of the analysis for at least one of the indicators for this indicator, a re-analysis of a sample taken from a double number of packaging units of sulfur of the same batch is carried out.

The results of the reanalysis apply to the entire batch.

4 METHODS OF ANALYSIS

4.1 Sampling and preparation of samples - by GOST 127.3.

4.2 Determination of the mass fraction of sulfur

4.2.1 Method Essence

The method is based on the weight loss determination after sample calcination at a temperature (250± 10) ° FROM.

4.2.2 Equipment:

Laboratory resistance electric furnace of the SNOL type, providing a stable heating temperature (250± 10) ° FROM;

Desiccator 2-230 according to GOST 25336;

Bowl 50 or crucible H-50 according to GOST 19908;

Single-burner electric stove according to GOST 14919.

4.2.3 Conducting an analysis

(20 ± 0.1) g of the sample is placed in a pre-calcined to constant weight and weighed bowl. The bowl is placed on an electric stove, the sulfur is slightly melted and set on fire. After the combustion of sulfur, the bowl is placed in an electric furnace, calcined at a temperature of (250± 10) ° C to constant weight, cool in a desiccator and weigh.

The results of all weighings in grams are recorded to the third decimal place.

4.2.4 Results processing

Mass fraction of sulfur in terms of dry matter X , %, calculated by the formula

( 1 )

where t- the weight of the weighed sample of the analyzed sample is with the bowl, g;

t 1 - the mass of the residue together with the bowl after calcination, g;

t 2 is the weight of the weighed portion of the analyzed sample, g.

The result of the analysis is taken as the arithmetic mean of the results of at least two parallel determinations, the allowable discrepancies between which do not exceed 0.05%.

4.3 The mass fraction of arsenic is determined by GOST 127.2.

4.4 The mass fraction of water is determined by GOST 127.2.

4.5 The residue on the sieve is determined by GOST 127.2.

5 TRANSPORT AND STORAGE

5.1 Sulfur is transported by all types of transport in covered vehicles in accordance with the rules for the transport of dangerous goods in force for this type of transport.

It is allowed to use open types of vehicles provided that they are protected from atmospheric precipitation.

5.2 Transportation of sulfur intended for export is carried out in accordance with the requirements of this standard or contract.

5.3 Sulfur, packed in bags, in packaged and unpackaged form, is stored indoors on wooden pallets.

Pallets with packaged sulfur are stacked. Between the stacks there must be a passage with a width of at least 0.75 m. It is not allowed to install pallets with sulfur near water pipes and heating appliances.

GOST 127.2-93

INTERSTATE STANDARD

SULFUR TECHNICAL

TEST METHODS

INTERSTATE COUNCIL
ON STANDARDIZATION, METROLOGY AND CERTIFICATION

Minsk

Foreword

1 DEVELOPED by the Research and Design Institute of the Sulfur Industry with a Pilot Plant, Ukraine INTRODUCED by the Technical Secretariat of the Interstate Council for Standardization, Metrology and Certification 2 ACCEPTED by the Interstate Council for Standardization, Metrology and Certification on October 21, 1993 (order No. 1 to protocol No. 4- 93) Voted for adoption:

State name	Name of the national standardization body
Republic of Armenia	Armstate standard
Republic of Belarus	Belstandard
The Republic of Kazakhstan	State Standard of the Republic of Kazakhstan
The Republic of Moldova	Moldova standard
Russian Federation	Gosstandart of Russia
Turkmenistan	Turkmenglavstate inspection
The Republic of Uzbekistan	Uzgosstandart
Ukraine	State Standard of Ukraine

3 Resolution of the Committee of the Russian Federation for Standardization, Metrology and Certification No. 199 dated March 21, 1996, the interstate standard GOST 127.2-93 was put into effect directly as a state standard from January 1, 1997. 4 INSTEAD OF GOST 127-76 (in terms of analysis methods)

INTERSTATE STANDARD

SULFUR TECHNICAL

Methods tests

Sulfur for industrial use.
Test methods

GOST
127.2-93

Introduction date 1997-01-01

This standard applies to technical sulfur liquid, lump and ground and establishes methods for testing its physical and chemical properties.

1 GENERAL REQUIREMENTS

1.1 The limits of application of the methods are indicated in Table 1. Table 1

Defined indicator	Analysis method	Limits of application of the method, mass fraction of the element, %	Section, paragraph of the standard containing the method of analysis
1 Sulfur	Estimated
2 Ash	weight	0.007 to 0.4
3 acids	Titrimetric	More than 0.001
4 Organic matter	gas volumetric	More than 0.005
	Spectral
	weight
	extraction
5 Arsenic	Photometric using silver diethyldithiocarbamate	0.00005 to 0.005
	Spectral	0.0001 to 1.0
	Photometric using molybdenum blue	0.005 to 0.1
6 selenium	Photometric using 3.3¢-diaminobenzidine	0.0005 to 0.04		Photometric using hydrazine sulfate
6 selenium	7 Iron	Photometric using O-phenanthroline	0.002 to 0.2
Spectral	7 Iron	0.001 to 1
8 Manganese	Photometric with formaldehyde oxime	0.0005 to 0.002		Photometric using potassium iodate
	Spectral	0.001 to 1
	9 Copper	Photometric using lead diethyldithiocarbamate	About 0.0005 to 0.001
Photometric using sodium diethyldithiocarbamate		0.0002 to 0.002
Spectral		0.001 to 1
10 Water	weight	More than 0.001
11 Particle size distribution	weight	0.001 to 0.01

1.2 The established confidence level (P), with which the determination error is within the limits specified in the methods of analysis, is 0.95. 1.3 The results of analyzes are rounded up to significant figures in accordance with the norms established by the standards for the corresponding type of sulfur. 1.4 When conducting analyzes and preparing solutions of reagents, if there are no other indications, the following are used: - reagents of qualifications not lower than pure for analysis (analytically pure); - distilled water according to GOST 6709; - general-purpose laboratory scales of the 2nd accuracy class according to GOST 24104 with the maximum weighing limit of 200 g; - a set of general-purpose weights of the 2nd accuracy class according to GOST 7328, weighing 210 g. 1.5 It is allowed to use any methods, measuring instruments and equipment for quality control that have passed metrological certification and have accuracy characteristics not lower than those given in this standard. In case of disagreement in the assessment of quality, the determination is carried out using the methods of this standard. 1.6 Preparation of solutions and reagents is carried out according to GOST 4212, GOST 4517, GOST 4919.1, GOST 4919.2, GOST 25794.1. 1.7 Calibration graphs are built once every three months and after each change of reagents. When constructing calibration graphs, each point should be the arithmetic mean of the results of three parallel measurements. 1.8 Sampling and preparation of samples in accordance with GOST 127.3.

2 DETERMINATION OF THE MASS FRACTION OF SULFUR

Mass fraction of sulfur in terms of dry matter X 1 , %, calculated by the formula

X 1 \u003d 100 - (X 2 + X 3 + X 5), (1)

Where X 2 - mass fraction of ash, determined according to Sec. 3,%; X 3 - mass fraction of acids in terms of sulfuric acid, determined according to Sec. four, %; X 5 - mass fraction of organic substances, determined according to Sec. 5, %.

3 DETERMINATION OF THE MASS FRACTION OF ASH

3.1 Essence of the method The method is based on the weight determination of the mass of the residue after calcination of the sample at a temperature of (800 ± 10) ° С. - desiccator 2-230 according to GOST 25336; - bowl 50 (80) or crucible H-50 (80) according to GOST 19908; - single-burner electric stove according to GOST 14919. 3.3 Analysis (20.0 ± 0.1) g of the sample is placed in a bowl, previously calcined and brought to constant weight. The bowl is placed on an electric stove, the sulfur is slightly melted and set on fire. The heating temperature is maintained at about 220 ° C, so that the sulfur burns slowly for 30 minutes until the sulfur is completely burned. Then the bowl is placed in an electric furnace, calcined at a temperature of (800 ± 10) ° C to constant weight, cooled in a desiccator and weighed. The results of all weighings in grams are recorded to the third decimal place. If the mass fraction of ash in sulfur is less than 0.02%, it is allowed to increase the sample up to 50.0 g. 3.4 Processing the results Mass fraction of ash X 2,%, calculated according to the formula

Where t 1 - mass of residue after calcination in an electric furnace, g; t- mass of the analyzed sample, g. The arithmetic mean of the results of two parallel determinations is taken as the result of the analysis, the absolute allowable discrepancy between which, as well as the absolute total error of the analysis results, do not exceed the values indicated in Table 2. Table 2 In percent

Mass fraction of ash	Permissible discrepancy	Total error
From 0.007 to 0.030 inclusive
St. 0.030 to 0.070"
"0.07 to 0.10"
"0.10 to 0.30"
"0.30 to 0.40"

4 DETERMINATION OF THE MASS FRACTION OF ACIDS IN CONVERSION TO SULFURIC ACID

4.1 Essence of the method The method is based on the extraction of acidic substances with water and titration of the resulting extract with sodium hydroxide or potassium hydroxide in the presence of phenolphthalein. 4.2 Apparatus, reagents and solutions: - pipette with a capacity of 100 cm 3 ; - burettes with a capacity of 5 and 10 cm 3; - beaker 250 according to GOST 1770; - cylinder 1-25 according to GOST 1770; - glass B-1-400 TC according to GOST 25336; - flask Kn-2-250-34 XC according to GOST 25336; - laboratory filter paper according to GOST 12026; - technical ethyl alcohol according to GOST 18300; - phenolphthalein (indicator), alcohol solution with a mass fraction of 1%; - potassium hydroxide according to GOST 24363 or sodium hydroxide according to GOST 4328, concentration solution With(KOH, NaOH) \u003d 0.01 mol / dm 3 (0.01 n.); - distilled water, not containing CO 2 ; prepared in accordance with GOST 4517. 4.3 Analysis (50 ± 1) g of sulfur is weighed, recording the weighing result in grams with an accuracy of three decimal places, placed in a glass, moistened with 25 cm 3 of ethyl alcohol and 200 cm 3 of water are added. The contents of the glass are stirred, the glass is covered with a watch glass and boiled for 15 - 20 minutes, stirring occasionally. After cooling, the contents of the beaker are filtered through a folded paper filter into a volumetric flask, the volume of the solution is adjusted to the mark with water free of CO 2 and mixed thoroughly. 100 cm 3 of the filtrate are taken into a conical flask, titrated from a burette with a solution of potassium or sodium hydroxide in the presence of phenolphthalein until a light pink color does not disappear within 1 minute. It is allowed to carry out titration using a potentiometer, taking pH = 8.2 - 8.3 as the equivalence point (end of titration). At the same time, a control experiment is carried out with a solution containing water and alcohol under the same conditions and with the same amount of reagents, but without the analyzed product. 4.4 Processing of results The mass fraction of acids in terms of sulfuric acid X 3,%, is calculated by the formula

(3)

Where V 1 - the volume of sodium or potassium hydroxide solution used for titration of the analyzed solution, cm 3; V 2 - volume of sodium or potassium hydroxide solution used for titration of the control sample solution, cm 3 ; 0.00049 is the mass of sulfuric acid corresponding to 1 cm 3 of a solution of sodium or potassium hydroxide with a concentration of exactly 0.01 mol / dm 3, g; t- mass of sulfur sample, g; To- correction factor to bring the concentration of sodium or potassium hydroxide solution to exactly 0.01 mol/dm 3 . The arithmetic mean of the results of two parallel determinations is taken as the result of the analysis, the absolute allowable difference between which, as well as the absolute values of the total error of the result of the analysis, do not exceed the values indicated in Table 3. Table 3 In percent

5 DETERMINATION OF THE MASS FRACTION OF ORGANIC SUBSTANCES

5.1 Gas volume method 5.1.1 Method Essence The method is based on burning a sulfur sample in a furnace in an oxygen stream and absorbing the released carbon dioxide with a potassium hydroxide solution. 5.1.2 - installation for determining carbon (Figure 1); - stopwatch; - pipette; - asbestos, calcined at a temperature of (800 ± 25) ° C, is stored in a desiccator; - desiccator 2-230 according to GOST 25336;

1 - oxygen balloon, 2 - reducer; 3 - gasometer or rotameter according to GOST 13045; 4 - flask SPZH-250 according to GOST 25336; 5 - bottle 3-0.5 according to GOST 25336; 6 - connecting glass tap K1X according to GOST 7995; 7 , 14 - traffic jams; 8 - tube made of transparent quartz glass or porcelain; 9 - tubular furnace, providing a stable heating temperature (850 ± 50) ° С; 10 , 11 - LSG boat according to GOST 9147; 12 - copper mesh or copper wire MM-0.5 according to GOST 2112; 13 - tubular furnace, providing a stable heating temperature (525 ± 25) ° С; 15 - pipes TX-2-100 according to GOST 25336; 16 - bottle CH-2 according to GOST 25336; 17 - bottle CH-1-100 according to GOST 25336; 18 - 32 - gas analyzer GOU-1

Figure 1 - Installation for the determination of carbon

Cotton wool absorbent according to GOST 5556; - glass wool; - calcium carbonate according to GOST 4530; - potassium hydroxide according to GOST 24363, solution with a mass fraction of 35%; - chromium (VI) oxide according to GOST 3776, the chromium mixture is prepared as follows: 4 g of chromic anhydride is dissolved in 10 cm 3 of water, then 5 cm 3 of sulfuric acid are added in small portions with constant stirring; - sodium sulfate 10-water according to GOST 4171, a solution with a mass fraction of 20% or sodium sulfate anhydrous according to GOST 4166, a solution with a mass fraction of 10%, saturated with carbon dioxide or oxygen. 5 - 6 drops of sulfuric acid and a few drops of methyl orange (barrier liquid) are added to the solution; - calcium or barium silicate, not containing CO 2 ; in the presence of CO 2, calcium or barium silicate is calcined in an electric resistance furnace, then in a combustion pipe at (950 ± 10) ° C in a stream of oxygen or sulfur dioxide; - copper oxide granulated according to GOST 16539, copper mesh, wire or shavings; - methyl orange (indicator), aqueous solution with a mass fraction of 0.1%; - potassium permanganate according to GOST 20490, solution with a mass fraction of 5%; - ascarite; - calcium chloride; - sulfuric acid according to GOST 4204; - a comparison sample of sulfur with a mass fraction of carbon of 0.03% for sulfur grades 9998, 9995, 9990 and 0.15% for other grades. The reference sample is prepared according to 5.2.3. 5.1.3 Preparation for analysis A quartz or porcelain tube 8 is inserted into the furnaces 9 and 13, which must protrude from the furnaces by at least 175 mm on each side. Both ends of the pipe are closed with plugs 7 and 14, into the holes of which one-way glass taps 6 are inserted. In the pipe 8 of the furnace 13, between the asbestos plugs, a copper mesh 12 is placed, rolled up in the form of a cylinder, sprinkled with calcium silicate (barium) containing no CO 2 . Instead of mesh, copper wire, copper shavings or copper oxide can be used. To burn a sulfur sample, oxygen is supplied to the furnace from a cylinder 1 with a reducer 2 or from a gas meter 3. Oxygen is purified by passing through a Tishchenko flask 4 containing a solution of potassium permanganate in a solution of potassium hydroxide, then through a column 5 for dry absorbers, filled at the bottom with glass beads, and above, with ascarite and calcium chloride, separated by glass or absorbent wool. The oxygen supply is regulated by a valve 6. Gases from the furnace for cleaning sulfur combustion products are passed sequentially through a U-shaped tube 15 filled with glass or absorbent wool (to retain solid particles entrained in gas and condensing sulfuric acid mist), through a buffer bottle 6, preventing transferring chromic anhydride into a U-shaped tube 15, through two absorption bottles 17 containing 50 cm 3 of a solution of chromic anhydride in sulfuric acid. After that, the gas enters the gas analyzer type GOU-1 to measure the volume of carbon dioxide. The gas analyzer type GOU-1 consists of a gas measuring burette (eudiometer) * 24 with a capacity of 250 cm 3 with an automatic shutter - a float 22, a thermometer 23 and a scale 26, a refrigerator 25 and an absorption vessel 18 filled with a solution of potassium hydroxide and equipped with an automatic shutter-float 22. The divisions of the scale show the percentage of carbon in sulfur at 1 g. Burette 24 has double walls (jacket), the space between which is filled with water through a special hole at the top of the burette to maintain a constant temperature. The equalizing bottle 27 has a side tube 31, a stopper 32 that can be closed. From 400 to 500 cm 3 of an aqueous solution of sodium sulfate is poured into the bottle 27 and closed with a rubber stopper 29, into the hole of which a three-way valve 28 with a rubber bulb 30 is inserted. Using a bulb, the gas mixture is pumped from burettes 24 into the absorption vessel 18 and back. Before starting operation, furnaces 9 and 13 are heated to a temperature of (850 ± 50) ° C and (525 ± 25) ° C, respectively. Check all connections and taps for tightness and bring the device into working condition. To do this, the valve 21 of the comb 19 is placed in a position in which the burette 24, the absorption vessel 18 and the refrigerator 25 are separated from each other. Having opened the valve 29 to connect the burette 24 with the atmosphere, using the equalizing bottle 27 and pear 30, fill the burette 24 with the sealing liquid (in this case, the valve 28 of the equalizing bottle 27 is put in the position of separation from the atmosphere, and the tube 31 is closed with a stopper 32). As soon as the liquid fills the burette 24, the valve 20 is closed, the valve 21 is put in a position in which the burette 24 is connected to the absorption vessel 18. The valve 28 of the equalizing bottle 27 is connected to the atmosphere, while the liquid from the burette 24 begins to drain into the bottle 27, the level of the alkali solution in the absorption vessel 18 rises, raising the float 22. As soon as the float closes the exit from the absorption vessel 18, the valve 21 of the comb 19 is placed in a position in which the burette 24, the absorption vessel 18 and the refrigerator 25 are disconnected from each other. The small valve 20 is again put on the connection of the burette with the atmosphere and, in the same way as indicated above, using the equalizing bottle 27, the valve 28 and the pear 30, the burette 24 is filled with liquid to the upper limit (the float closes the exit from the burette). When the burette 24 is filled with liquid, the valve 20 is closed, and the valve 28 of the equalizing bottle 27 is connected to the atmosphere. If the device is sealed, then the absorption vessel 18 remains filled, and the liquid level in the buret remains unchanged. The constancy of the level is observed when the liquid is in the narrow part of the burette 24, the reading is carried out according to the divisions of the scale 26. If the levels of the solutions fall, then the device is not airtight, it should be disassembled, wipe the taps, lubricate them with Vaseline and re-check for leaks. 5.1.4 Analysis conditions The measuring burette must be thoroughly cleaned of contamination by washing with chromium mixture and then with distilled water. When reading the burette scale, it is always necessary to bring the tube 31 of the equalizing bottle 27 to the burette in the same way, holding it so that the liquid is always at the same level. The hose connecting the burette to the equalizing bottle must always be in the same position and not hang down from the table. Burette readings can only be taken after 15 - 20 seconds of exposure (measured with a stopwatch), so that the liquid can completely drain from the walls. When 8 drops of sulfuric acid appear in the tube, calcium silicate (barium) is replaced with fresh. Porcelain or quartz boats 80 - 100 mm long are calcined in an oven at 800 - 900 ° C and stored in a desiccator. 5.1.5 Conducting an analysis Three boats 10 and 11 with calcium silicate (barium) are inserted into the combustion tube 8 using a copper hook through the hole for the plug 7 and the furnaces 9 and 13 are heated. As soon as the furnaces are heated to the appropriate temperatures, the gas analyzer is placed in working position , and the tube 8 is connected with the help of plugs 7 and 14 to the U-shaped tube 15 and to the tap 6, after which a control experiment is carried out, i.e. pass a current of oxygen through a heated tube 8 and observe the readings of the scale 26 of the burette 24 before and after absorption of carbon dioxide. As soon as carbon disappears from the system, the difference in the readings of the scale before and after the absorption of carbon dioxide will be equal to zero or will give the same value of the quantity (1 - 2 divisions of the scale), which is subtracted in the calculation. Then the operation of the device is checked using a sulfur comparison sample, for this, boats 10 and 11 are removed from the tube 8 of the furnace 9, 0.3 - 0.5 g of the sulfur comparison sample is placed in the boat 10, covered with calcium silicate (barium). Boats 10 and 11 are quickly pushed with a hook into the tube 8 of the furnace 9 and the tube is closed with a rubber stopper 7. Tap 6 is opened and a current of oxygen is passed from the gasometer 3 at a speed of 4 - 5 bubbles per second. The valve 21 must be adjusted so that the descent of the barrier liquid from the burette 24 into the flask 27 proceeds evenly (filling the burette 24 with gases should take about 1 - 1.5 minutes). In this case, the valve 28 of the equalizing bottle 27 is connected to the atmosphere. As soon as the narrow (lower) part of the burette is filled with gases and the liquid level reaches zero division of the scale 26, the valve 21 is put in the position of separation from the refrigerator 25, the burette 24 and the absorber 18, the oxygen supply is stopped (the valve 6 is closed), the liquids are allowed to drain from the walls and after 15 - 20 s, the volume of the resulting gas mixture is measured. To do this, the stopper 32 is removed from the tube 31 of the flask 27 and, by moving the flask 27 with the corresponding position of the valve 28 along the burette (next to it), they reach a position at which the liquid levels in the burette 24 and the tube 31 of the flask 27 are at the same level. The readings of the scale 26 are recorded, the tube 31 is closed with a stopper 32. The bottle 27 is separated with the atmosphere with a tap 28, the burette 24 is connected to the vessel 18 by turning the tap 21 and with the help of a pear 30 gaseous products are transferred 2 - 3 times from the burette 24 to the absorption vessel 18 and back. When transferring gas to the burette 24, the valve 28 of the equalizing bottle is placed in the position of communication with the atmosphere. Record the scale readings. The difference in readings before and after the absorption of CO 2 determine the amount of absorbed carbon dioxide. After measuring the volume of absorbed carbon dioxide with the help of a valve 20, the burette is released from gas, filled with a barrier liquid, and secondary combustion is carried out. The determination is considered complete if, during the control combustion of the sample, the difference between the readings before and after the absorption of CO 2 is equal to zero. At the end of each test, the temperature and atmospheric pressure are measured and, according to the table attached to the instrument, an amendment is found for the conditions under which the determination of carbon was carried out. The mass fraction of carbon in the analyzed sulfur is determined in the same way as in the reference sample. 5.1.6 Results processing Mass fraction of carbon X 4 , %, calculated according to the formula

Where V is the volume of carbon dioxide, expressed as a percentage of carbon; To- correction for temperature and pressure; t- mass of sulfur sample, g. Mass fraction of organic matter X 5 , %, calculated according to the formula

X 5 = X 4×1.25, (5)

Where X 4 - mass fraction of carbon, %; 1.25 is the conversion factor for carbon to organic matter. The arithmetic mean of the results of two parallel determinations is taken as the result of the analysis, the absolute permissible discrepancy between which, as well as the absolute total error of the analysis results, do not exceed the values indicated in Table 4. Table 4 In percent The gas volume method for determining the carbon content is arbitration. 5.2 Spectral method 5.2.1 Method Essence The method is based on photographing the spectra of samples and determining the total carbon from a calibration curve. 5.2.2 Equipment, materials and reagents: - ISP-30 spectrograph with a single-lens quartz condenser; - alternating current arc generator DG-2 in the low-voltage spark mode; - microphotometer type IFO-451 or MF-2, MF-4; - aluminum electrodes AD-1, 6 mm in diameter. At the ends of the electrodes, a cylindrical channel is drilled, with an outer diameter of 3 mm, an inner diameter of 2.5 mm, and a depth of 3–5 mm. Two electrodes filled with sample are used for operation. Aluminum electrodes made on a lathe or using a stamp are wiped and washed in acetone or benzene to remove traces of lubricating oils, dried under a draft and then fired on an aluminum baking sheet in an electric furnace at (500 ± 10) ° C for 20 min to remove traces of organic compounds. After cooling, the electrodes are placed in a closed glass jar and stored in a dry place; - an aluminum plate measuring 24 ´ 70 ´ 10 mm for dosing the filling of electrodes with samples, in which a flat recess 8 mm deep and 16 ´ 16 mm in size was made by a cutter; - aluminum foil for storing samples; - developer and fixer; - mortar agate or chrome-plated steel with a diameter of 90 mm; - sieve with mesh 0071N according to GOST 6613; - aluminum ruler; - electric resistance furnace of the SNOL type, providing a stable heating temperature (500 ± 10) ° С; - drying cabinet type SNOL, providing a stable temperature (80 ± 2) ° С; - cup SN-85/15 according to GOST 25336; - sulfur os.h. 16-5; - sulfur with a mass fraction of organic substances 0.3 - 0.5%; - acetone according to GOST 2603; - benzene according to GOST 5955. 5.2.3 Preparation for analysis To prepare the main sample, about 50 g of sulfur is crushed with a mass fraction of organic substances from 0.3 to 0.5%, sieved and kept in an oven at (80 ± 2) ° C for 20 hours until constant weight. Then determine the mass fraction of organic substances according to 5.1. The arithmetic mean of the results of ten parallel determinations is taken as the value of the mass fraction of organic substances. Comparison samples are prepared by mixing sulfur of the main sample with sulfur of special purity grade, previously crushed and sifted through a sieve. To do this, sulfur samples of the main sample weighing 20; 6 and 2 g are thoroughly mixed in a mortar, respectively, with weighed portions of sulfur of special purity grade. weighing 40, 54, 58 g. The results of all weighings in grams are recorded with an accuracy of the third decimal place. The mass fraction of carbon in the first sample is 0.1 - 0.2%, in the second sample - 0.003 - 0.06% and in the third sample - 0.01 - 0.02%. Samples were stored in glass cups with ground stoppers. The reference samples are introduced into the electrodes (upper and lower), for which the sample is placed on the dosing plate before shooting in an even layer, which rises above the plate by 3–5 mm. With the edge of an aluminum ruler, 5-6 successive cuts of the powder layer in the form of a rectangular grid are made, then the excess powder is cut off with the same ruler. The electrode is pressed into the powder layer until it stops at the bottom of the plate and is removed from it with a slight turn. A low-voltage spark with a current of 6 A is ignited between the electrodes. The distance between the electrodes is 2 mm, the exposure is 25 s, the gap width is 0.01 mm. Based on the results of photometry of the spectra of reference samples, a calibration graph is built, plotting the logarithm of the mass fraction of carbon (lgC) in sulfur along the abscissa axis, and blackening (S) on the spectrogram of the analytical carbon line at 247.86 nm and the background near it along the ordinate axis. 5.2.4 Conducting an analysis The analyzed sample is crushed, sieved, injected into the electrodes and photometrically carried out according to clause 5.2.3. The mass fraction of carbon is found according to the calibration curve. 5.2.5 Results processing Mass fraction of organic matter X 5 , %, calculated according to the formula

X 5 = X 4×1.25, (6)

Where X 4 - mass fraction of carbon in sulfur, found according to the calibration curve, %; 1.25 is the conversion factor for carbon to organic matter. The result of the analysis is taken as the arithmetic mean of the results of two parallel determinations, the relative discrepancy between which does not exceed the allowable discrepancy equal to 30% of the average value. Limits of permissible relative total error of the analysis result ± 15%. 5.3 Weight method 5.3.1 Method Essence The method is based on the weight determination of residues by mass difference after double calcination of the sample at a temperature of (250 ± 10) ° С and (800 ± 10) ° С. 10) ° С and (250 ± 10) ° С; - desiccator 2-230 according to GOST 25336; - bowl 50 according to GOST 19908; - sand bath. 5.3.3 Conducting an analysis(50 ± 1) g of the sample is placed in a bowl, previously calcined and weighed. The sample is melted and fired in a sand bath. Then the bowl with the residue is calcined at a temperature of (250 ± 10) ° C for 2 hours to remove traces of sulfur. The bowl with the residue, consisting of organic matter and ash, is transferred to a desiccator, cooled and weighed. Then the bowl with the residue is placed in an electric furnace, calcined at a temperature of (800 ± 10) ° C to constant weight, cooled in a desiccator and weighed. The results of all weighings in grams are recorded to the third decimal place. 5.3.4 Results processing X 5 , %, calculated according to the formula

Where t- mass of the analyzed sample, g; m l is the mass of the residue containing organic matter and ash, g; t 2 - the mass of the residue after calcination in an electric furnace, g. The arithmetic mean of the results of two parallel determinations is taken as the result of the analysis, the relative discrepancy between which does not exceed the allowable discrepancy, equal to 30% of the average value. Limits of permissible relative total error of the analysis result ± 15%. 5.4 Extraction method 5.4.1 Method Essence The method is based on the extraction of organic substances with chloroform or carbon tetrachloride in a Soxhlet apparatus and the weight determination of the residue after evaporation of the solvent. The method cannot be applied in the presence of volatile organic substances soluble in water. 5.4.2 Equipment, reagents and solutions: - nozzle NET-100 TC according to GOST 25336; - drying cabinet type SNOL, providing a stable heating temperature (70 ± 2) ° С; - water bath or single-burner electric stove according to GOST 14919; - glass V-1-400 THS according to GOST 25336; - cylinder 1-250 according to GOST 1770; - desiccator 1-230 according to GOST 25336; - water jet pump according to GOST 25336; - evaporation bowl 4 according to GOST 9147; - laboratory filter paper according to GOST 12026; - technical ethyl alcohol according to GOST 18300; - chloroform or carbon tetrachloride according to GOST 20288, freshly distilled; - sodium sulphide 9-water according to GOST 2053, solution with a mass fraction of 45% (the solution must be transparent). 5.4.3 Conducting an analysis(25 ± 1) g of sulfur is placed in a beaker, moistened with 10 cm 3 of ethyl alcohol, stirred with a glass rod, then 200 cm 3 of sodium sulfide solution are added, the solution is heated on a water bath to (80 ± 2) ° C and stirred at this temperature until complete dissolution of sulfur. After cooling to room temperature, the solution is filtered through paper filters previously extracted with chloroform or carbon tetrachloride. The residue on the filter is washed three times with a warm solution of sodium sulfide and warm distilled water until the filter is completely discolored, dried for 30 minutes. in a desiccator under vacuum using a water-jet pump and extracted in a Soxhlet apparatus until the solvent in the upper part of the apparatus is completely discolored. At the end of the extraction, transfer the extract quantitatively to a glass evaporating bowl, previously dried and weighed. The evaporating bowl with the extract is placed in a water bath, the solvent is distilled off under a fume hood, the residue is dried in an oven at (70 ± 2) °C to constant weight and weighed. The results of all weighings in grams are recorded to the third decimal place. 5.4.4 Results processing Mass fraction of organic substances X 5 , %, calculated according to the formula

, (8)

Where m l is the mass of the evaporation bowl with organic substances, g; m 2 - mass of the evaporation bowl, g; t is the weight of the analyzed sample, g. The arithmetic mean of the results of two parallel determinations is taken as the result of the analysis, the relative discrepancy between which does not exceed the allowable discrepancy, equal to 25% of the average value. Limits of permissible relative total error of the analysis result ± 10%.

6 DETERMINATION OF THE MASS FRACTION OF ARSENIC

6.1 Photometric method using silver diethyldithiocarbamate 6.1.1 Method Essence The method is based on the reduction of arsenic to arsenic hydrogen, its absorption by a pyridine solution of silver diethyldithiocarbamate, and photometric measurement of the optical density of the resulting solution. 6.1.2 Apparatus, reagents and solutions: - installation for the determination of arsenic (Figure 2) or a distillation apparatus for distillation of arsenic according to GOST 10485-75, consisting of a reaction flask (a conical flask with a capacity of 100 cm 3), an outlet tube expanded in the upper part and narrowed at the bottom, test tubes with a capacity of 10 cm 3. The outlet tube is connected to the reaction flask through a thin section; - spectrophotometer of the SF type with a visible radiation limit and cuvettes with a thickness of the light-absorbing solution layer of 1 cm or a photoelectrocalorimeter of the FEK type; - water bath; - sand bath; - flasks 2-1000-2, 2-100-2, 2-50-2 according to GOST 1770; - flasks Kn-500-34 TU and Kn-1-100-19/26 TS according to GOST 25336; - cylinder 1-100 according to GOST 1770; - pipettes with a capacity of 1, 2, 5, 10 and 25 cm 3; - sulfuric acid according to GOST 4204, diluted 1:2; - arsenic anhydride according to GOST 1973; - nitric acid according to GOST 4461, density 1.4 g/cm 3 ; - sulfuric acid according to GOST 4204, free from arsenic, density 1.84 g / cm 3, concentration c (1/2 H 2 SO 4) \u003d 21.5 mol / dm 3 (21.5 n.);

1 - conical flask with a capacity of 100 cm 3; 2 - nozzle for absorption of hydrogen sulfide; 3 - rubber stopper; 4 - absorber for absorption ASH 3, manufactured according to the specified dimensions.

Figure 2 - Installation for the determination of arsenic

Hydrochloric acid according to GOST 3118; - carbon tetrachloride according to GOST 20288, chemically pure; - bromine according to GOST 4109; - a mixture of bromine and carbon tetrachloride, taken 2:3; - tin dichloride, solution with a mass fraction of 40%; - granulated zinc, chemically pure, free from arsenic; - lead acetic according to GOST 1027, chemically pure, saturated solution; - potassium iodide according to GOST 4232, solution with a mass fraction of 15%; - pyridine according to GOST 13647; - silver diethyldithiocarbamate, a solution with a mass fraction of 0.5%, is prepared as follows: 1 g of silver diethyldithiocarbamate is dissolved in 200 cm 3 of pyridine. The solution is stored in dark glass bottles. The solution is stable for 14 days; - cotton wool in accordance with GOST 4517, impregnated with a solution of lead acetate; - arsenic, the main solution with a mass concentration of 0.1 mg/cm 3 prepared according to GOST 4212; - arsenic, a working solution with a mass concentration of 0.0025 mg / cm 3, is prepared as follows: 25 cm 3 of the stock solution is taken into a volumetric flask with a capacity of 1 dm 3 and topped up with water to the mark. 6.1.3 Preparation for analysis To build a calibration graph in conical flasks with a capacity of 100 cm 3, 1 is taken in turn; 2; 3; four; 6 and 8 cm 3 working solution containing, respectively, 0.0025; 0.005; 0.0075; 0.010, 0.011 and 0.020 mg of arsenic, add 10 cm 3 of sulfuric acid solution and add water to 40 cm 3, add 2 cm 3 of potassium iodide solution, 2 cm 3 of tin dichloride solution and leave the solution for 15 minutes. In the nozzle 2 of the installation (Figure 2), cotton wool impregnated with lead acetate is placed, and 5 cm 3 of silver diethyldithiocarbamate solution is poured into absorber 4. After 15 min. 5 g of zinc are placed in a conical flask with a solution and the flask is quickly connected with a nozzle and an absorber. The released arsenic hydrogen is absorbed with a solution of silver diethyldithiocarbamate in pyridine for 45 minutes. Then the solution is topped up with pyridine to a volume of 5 cm 3 , mixed in an absorber, and the optical plane of the solution is measured at a wavelength of 540 nm, using a solution of silver diethyldithiocarbamate in pyridine as a reference solution. On the basis of the obtained results, a calibration graph is built, plotting the mass of arsenic in milligrams on the abscissa axis, and the corresponding value of optical density on the ordinate axis. 6.1.4 Conducting an analysis To prepare a solution of the analyzed sample (10 ± 1) g of sulfur is weighed, recording the weighing result in grams with an accuracy of the fourth decimal place, placed in a conical flask with a wide neck with a capacity of 500 cm 3, add 40 cm 3 of a mixture of bromine with carbon tetrachloride, mix the contents flasks for about 30 minutes, after which small portions of 1 - 2 cm 3 50 cm 3 of nitric acid are introduced with constant stirring. After adding the first portion, wait until the temperature of the mixture rises sharply, and only then add the same portions of nitric acid, expecting a faster release of bromine, an increase in temperature and a weak boiling of the mixture. In the case of a strong heating of the mixture (sudden and prolonged intensive release of bromine), the flask is cooled in a mixture of water with ice before adding each new portion of nitric acid. The entire operation is carried out in a fume hood, observing safety precautions. With incomplete decomposition of sulfur, the decomposition operations are repeated using a smaller number of reagents. Excess bromine and carbon tetrachloride are eliminated by heating the solution first in a water bath, and then in a sand bath until white fumes appear. The solution is cooled, 25 cm 3 of water are added and evaporated until white fumes appear, this operation is repeated three times until the nitric acid is completely removed. The residue is cooled, transferred to a volumetric flask with a capacity of 50 cm 3 and topped up with water to the mark. (The solution is used to determine the mass fraction of selenium by the photometric method). To prepare a control solution, 40 cm 3 of a mixture of bromine with carbon tetrachloride and 50 cm 3 of nitric acid are evaporated to a volume of several milliliters, 2 cm 3 of a sulfuric acid solution are added, evaporated to white fumes, 5 cm 3 of water are added and the evaporation is repeated. After cooling, the residue is poured into a solution of sulfuric acid (1:2), poured into a volumetric flask with a capacity of 50 cm 3 and topped up to the mark with the same solution of sulfuric acid. 25 cm 3 of the resulting solution is taken into a flask with a capacity of 100 cm 3, 2 cm 3 of a sulfuric acid solution (1: 2) are added and topped up with water to a volume of 40 cm 3, then the analysis is carried out according to clause 6.1.3., measuring the optical density of the analyzed solution relative to the control solution. The mass of arsenic in milligrams in the analyzed solution is found according to the calibration curve. 6.1.5 Results processing Mass fraction of arsenic X 6 , %, calculated according to the formula

Where t t is the weight of the weighed portion of the analyzed sample, g; V- the volume of the solution selected for determination, cm 3 . The result of the analysis is taken as the arithmetic mean of the results of two parallel determinations, the relative discrepancy between which does not exceed the allowable discrepancy equal to 30% of the average value. Limits of permissible relative total error of the analysis result ± 15%. Determination of the mass fraction of arsenic by a photometric method using silver diethyldithiocarbamate is arbitrary. 6.2 Spectral method 6.2.1 Method Essence The method is based on photographing the spectra of samples and determining arsenic from a calibration curve. 6.2.2 Equipment, materials and solutions: - ISP-30 spectrograph with a single-lens illumination system; - alternating current arc generator DG-2 in arc mode and low-voltage spark mode; - microphotometer type IFO-451 or MF-4, MF-2; - device for sharpening carbon electrodes; - carbon electrodes special purity grade 7-4 or C-1. Lower and upper electrode with a crater 4 mm in diameter, 5 mm deep. Prior to analysis, carbon electrodes are analyzed for the absence of arsenic lines in their spectra under the conditions of the analysis method. In the presence of arsenic lines, the electrodes are fired for 20 seconds in the analysis mode; - dosing plate made of organic glass for filling the electrodes with a sample 24 ´ 70 ´ 8 mm in size, in which a flat recess 6 mm deep and 16 ´ 16 mm in size was made by a cutter; - spectrographic photographic plates of type 1 and 3 spectral sensitivity in relative units, equal to 6 and 9 units, respectively; - photographic plates of the UVS type with a spectral sensitivity of 20 units; - quartz condenser (F = 75 mm); - mortar agate or chrome-plated steel with a diameter of 90 mm; - cup CH 85/15 according to GOST 25336; - sieve with mesh 0071 H according to GOST 6613; - developer and fixer; - technical ethyl alcohol according to GOST 18300, distilled; - sulfur os.h. 16-5; - sulfur with a mass fraction of arsenic from 0.3 to 0.6%. 6.2.3 Preparation for analysis To prepare the main sample, about 50 g of sulfur is crushed with a mass fraction of arsenic from 0.3 to 0.6%, then sieved through a sieve and the value of the mass fraction of arsenic is determined according to clause 6.1. Comparison samples are prepared by successive mixing of sulfur of the main sample with sulfur of special purity grade, preliminarily crushed and sifted through a sieve. To do this, sulfur samples of the main sample weighing 20 and 6 g are thoroughly mixed in a mortar under alcohol, respectively, with sulfur samples of special purity grade. weighing 40 and 54 g. Thus, the first and second comparison samples were obtained with a mass fraction from 0.1 to 0.2 and from 0.03 to 0.06% arsenic. The third and fourth comparison samples with a mass fraction of arsenic from 0.01 to 0.02 and from 0.003 to 0.006% are prepared in a similar way, using 20 and 6 g of sulfur of the second comparison sample as the basis. They are mixed, respectively, with 40 and 54 g of sulfur of special purity grade. Using the sulfur of the fourth comparison sample, the fifth and sixth comparison samples are prepared with a mass fraction of arsenic from 0.001 to 0.002 and from 0.0003 to 0.0006% by mixing 20 and 6 g of the fourth comparison sample, respectively, with 40 and 54 g of os.p. . The seventh comparison sample with a mass fraction of arsenic from 0.0001 to 0.0002% is prepared by mixing 20 g of sulfur of the sixth sample and 40 g of sulfur of special purity grade. The results of all weighings in grams are recorded to the fourth decimal place. To prepare one reference sample, 100 cm 3 of alcohol are used. The obtained samples are stored in cups. Reference samples are introduced into the electrodes (upper and lower) and photometered: a) at a mass fraction of arsenic from 0.0001 to 0.01%. Between the electrodes, an alternating current arc is ignited from a DG-2 generator, with a current of 18 A (with an additional rheostat turned on - 11 Ohm; 15 A). Distance between electrodes 2.5 mm, exposure 15 s. The spectra of reference samples are photographed three times with a spectrograph (a quartz condenser with F = 75 mm is installed at a distance of 67 mm from the source and 316 mm from the slit), with a spectrograph slit width of 0.025 mm. To photograph the spectra of arsenic, photographic plates "spectral, type 3" or "UFSH-3" are used. On the obtained spectrograms, the blackening of the analytical line of arsenic at 228.81 nm (or 234.98 nm) and the background near the analytical line are measured; b) with a mass fraction of arsenic from 0.001 to 0.6%. A low-voltage spark is ignited between the electrodes from a DG-2 generator with a current of 5 A (rheostat switch position 80 Ohm, 10 A). Distance between electrodes 2.5 mm, exposure 15 s. The spectra of reference samples are photographed three times with a spectrograph with a spectrograph slit width of 0.015 mm. To photograph the spectra of arsenic, spectral photographic plates, type 1, are used. On the obtained spectrograms, blackening of the analytical lines of arsenic 234.98 nm (with a mass fraction of arsenic from 0.001 to 0.1%) and 245.65 nm (with a mass fraction of arsenic from 0.1 up to 0.6%) and the background near the analytical lines. Based on the results of photometry of the spectra of reference samples, a calibration graph is built, plotting the logarithm of the mass fraction of arsenic on the abscissa axis, and blackening of the analytical lines on the ordinate axis. 6.2.4 Conducting an analysis The analyzed sample is crushed, sieved, injected into the electrodes (upper and lower) and photometered according to 6.2.3. According to the results of photometry of the spectra of samples, the mass fraction of arsenic in the analyzed sample is found from the calibration curve. The result of the analysis is taken as the arithmetic mean of the results of two parallel determinations, the relative discrepancy between which does not exceed the allowable discrepancy equal to 30% of the average value. 6.3 Molybdenum blue photometric method 6.3.1 Method Essence The method is based on the formation of a complex of arsenic with ammonium molybdate in the presence of hydrazine sulfate and photometric measurement of the optical density of the complex obtained. 6.3.2 Equipment, reagents and solutions: - photoelectrocolorimeter type FEK-56, FEK-60; - a spectrophotometer with a visible radiation limit and cuvettes with a thickness of the light-absorbing solution layer of 1 cm, type SF; - Laboratory resistance electric furnace of the SNOL type, providing a stable heating temperature (500 ± 10) ° С; - drying cabinet type SNOL, providing a stable heating temperature (130 ± 5) ° С; - Buechner funnel according to GOST 9147; - flasks 2-100-2, 2-1000-2, 2-50-2 according to GOST 1770; - pipette with a capacity of 10 cm 3; - a burette with a capacity of 50 cm 3: - a water bath or a single-burner electric stove according to GOST 14919; - crucible H-20 according to GOST 19908; - glass B-1-100 according to GOST 25336; - laboratory filter paper according to GOST 12026; - nitric acid according to GOST 4461, density 1.4 g/cm 3 ; - sulfuric acid according to GOST 4204, chemically pure, 5 N. solution; - potassium pyrosulfate according to GOST 7172, chemically pure; - ammonium molybdate according to GOST 3765; recrystallized, solution with a mass fraction of 1%. Recrystallization is carried out as follows: 200 g of ammonium molybdate is thoroughly shaken with 300 cm 3 of a distilled hearth heated to 70 - 80 ° C. The undissolved precipitate is filtered off, and 1/3 by volume of ethyl alcohol is added to the filtrate. The precipitated finely crystalline precipitate of pure ammonium molybdate is filtered off on a Buchner funnel with suction. The filter cake is washed three times with alcohol and dried in air; - hydrazine sulfate according to GOST 5841, crystalline, solution with a mass fraction of 0.15%; - rectified technical ethyl alcohol in accordance with GOST 18300; - arsenic anhydride according to GOST 1973; - the main solution with a mass concentration of arsenic 1 mg / cm 3 is prepared according to GOST 4212 or as follows: 0.1320 g of arsenic anhydride, weighed in a glass, is oxidized with 5 cm 3 of concentrated nitric acid, evaporated almost to dryness and dried in an oven at (130 ± 5) ° C for half an hour. The residue in the beaker is dissolved in distilled water, transferred to a volumetric flask with a capacity of 100 cm 3 . The glass is washed off several times with water into the same flask, the solution in the flask is brought to the mark with water and mixed thoroughly; - a working solution with a mass concentration of arsenic of 0.01 mg/cm 3 is prepared as follows: 10 cm 3 of the main solution is taken with a pipette with a rubber pear into a volumetric flask with a capacity of 1 dm 3, brought to the mark with water and mixed. 6.3.3 Preparation for analysis To build a calibration graph in volumetric flasks with a capacity of 50 cm 3, 3 are taken in turn; 5; ten; fifteen; 20 and 30 cm 3 of the working solution, which contain, respectively, 0.03; 0.05; 0.10; 0.15; 0.20 and 0.30 mg arsenic. The volume of the solution in each flask is adjusted with water to 35-40 cm 3 . Then, 3 cm 3 of a solution of sulfuric acid, a solution of ammonium molybdate and a solution of hydrazine sulfate are added successively to each flask. The contents of the flask are shaken after adding each reagent. The flasks with solutions are placed in a boiling water bath for 10 minutes so that the part of the flask filled with liquid is immersed in water. Then the flasks are cooled, brought to the mark with distilled water, and the optical density of the solutions is measured relative to the control solution, which is prepared under the same conditions and with the same amount of reagents, but without a working solution, using a red light filter with a light transmission region of 835 nm. Based on the data obtained, a calibration graph is built, plotting the mass of arsenic in milligrams on the abscissa axis, and the corresponding value of optical density on the ordinate axis. 6.3.4 Conducting an analysis 0.3 - 0.6 g of sulfur (depending on the arsenic content) is weighed, recording the weighing result in grams to the fourth decimal place, mixed in a quartz crucible with 2.2 g of potassium pyrosulfate. The crucible is placed in an electric furnace and the temperature is gradually increased to (500 ± 10) ° C. The crucible is kept at this temperature until all the sulfur is sublimated and the alloy becomes transparent. After that, the crucible is removed from the electric furnace, cooled, placed in a glass and the contents are leached with small amounts of water while heating. The solution from the glass is transferred to a volumetric flask with a capacity of 50 cm 3 and the glass is washed several times with small portions of water, which are added to the same flask. Then sequentially add 3 cm 3 of a solution of sulfuric acid, a solution of ammonium molybdate and a solution of hydrazine sulfate. The contents of the flask are shaken after adding each solution. The flask is placed for 10 minutes in a boiling water bath so that the part of the flask filled with liquid is immersed in water. Then the flask is cooled, brought to the mark with water and the optical density of the analyzed solution is measured relative to the control solution according to 6.3.3. The mass of arsenic in the analyzed solution is found according to the calibration curve. 6.3.5 Results processing Mass fraction of arsenic X 6 , %, calculated by the formula

Where t 1 - mass of arsenic, found according to the calibration curve, mg; t is the weight of the sulfur sample, g. The arithmetic mean of the results of two parallel determinations is taken as the result of the analysis, the relative allowable discrepancy between which does not exceed the allowable discrepancy equal to 30% of the average value. Limits of permissible relative total error of the analysis result ± 15%.

7 DETERMINATION OF THE MASS FRACTION OF SELENIUM

7.1 Photometric method using 3.3 ¢ - diaminobenzidine 7.1.1 Method Essence The method is based on the photometric measurement of the optical density of the yellow toluene extract of the complex formed by selenium (IV) with hydrochloric acid 3.3 ¢ -diaminobenzidine. 7.1.2 Apparatus, reagents and solutions: - Spectrophotometer type SF with a visible radiation limit and cuvettes with a thickness of the light-absorbing solution layer of 1 cm; - universal ion meter EV-74; - glass B-1-100 XC according to GOST 25336; - funnel VD-1-100 XC according to GOST 25336; - flask 2-10-2 according to GOST 1770; - pipettes with a capacity of 1, 2, 5, 10, 25 and 50 cm 3; - absorbent cotton wool according to GOST 5556; - microwave grade selenium; - 3.3 ¢ - diaminobenzidine hydrochloric acid, solution with a mass fraction of 0.5%; prepared using distilled freshly boiled chilled water; the solution is stable for 4 hours; - sulfuric acid according to GOST 4204, solution with a mass fraction of 10%; - disodium salt of ethylenediamine-N, N, N ¢, N ¢, -tetraacetic acid, 2-water (trilon B) according to GOST 10652, concentration solution c (C 10 H 14 N 2 Na 2 O 8 × 2 H 2 0) \u003d 0.1 mol / dm 3; - formic acid according to GOST 5848, solution with a mass fraction of 10%; - aqueous ammonia according to GOST 3760, solution with a mass fraction of 10%; - toluene according to GOST 5789; - ammonium chloride according to GOST 3773; solution with a mass fraction of 20%; - universal paper indicator; - selenium, the main solution with a mass concentration of selenium 1 mg/cm 3 is prepared according to GOST 4212; - selenium, a working solution with a selenium mass concentration of 0.01 mg/cm 3 is prepared as follows: the stock solution is diluted 100-fold with water. 7.1.3 Preparation for analysis To build a calibration graph, 1, 2, 3, 4 cm 3 of the working solution are taken in turn in glasses with a capacity of 100 cm 3, 50 cm 3 of an ammonium chloride solution are added, then a sulfuric acid solution until the pH of the solution is 2.5, determining the pH with a potentiometer or paper indicator, add 2 cm 3 of formic acid solution and 4 cm 3 of 3.3 ¢ -diaminobenzidine hydrochloric acid solution, stir with a glass rod and leave for 40 minutes, then add aqueous ammonia solution, adjust the pH of the solution to 6 - 7, transfer to a separating funnel with a capacity of 100 cm 3, add 10 cm 3 of toluene in two portions (6 and 4 cm 3), each time shaking for 1 min. After adding each portion, separate the layer of toluene, filter through cotton wool into a volumetric flask with a capacity of 10 cm 3 and add toluene to the mark. The solution is placed in cuvettes and the optical density is measured relative to the optical density of toluene at a wavelength of 420 nm. On the basis of the results obtained, a calibration graph is built, plotting the mass of selenium in milligrams on the abscissa axis, and the corresponding optical density value on the ordinate axis. 7.1.4 Conducting an analysis In a glass with a capacity of 100 cm 3, 10 - 25 cm 3 of a solution of the analyzed sample prepared according to 6.1.4 are taken, 50 cm 3 of an ammonium chloride solution, 5 cm 3 of a solution of Trilon B are added. Then, adding a solution of aqueous ammonia, bring the pH of the solution to 2, 5, measuring the pH with a potentiometer or paper indicator. Add 2 cm 3 of a solution of formic acid, 4 cm 3 of a solution of hydrochloric acid 3,3 ¢ -diaminobenzidine, stir the solution with a glass rod and leave for 40 minutes, then add a solution of aqueous ammonia, adjust the pH of the solution to 6 - 7, transfer to a separating funnel with a capacity of 100 cm 3 , add 10 cm 3 toluene in two portions (6 and 4 cm 3 ) each time shaking for 1 minute. After each addition, the toluene layer should be separated by filtering through cotton wool into a volumetric flask with a capacity of 10 cm 3 and topped up with toluene to the mark. Measurement of optical density is carried out according to 7.1.3. The mass of selenium in milligrams is determined from the calibration curve. 7.1.5 Results processing calculated according to the formula

(11)

Where t 1 - mass of selenium in the analyzed solution, determined according to the calibration curve, mg; t- mass of sulfur sample, g; V- the volume of the solution selected for analysis, cm 3 . The result of the analysis is taken as the arithmetic mean of the results of two parallel determinations, the relative discrepancy between which does not exceed the allowable discrepancy, equal to 15% of the average value. Limits of permissible relative total error of the analysis result ± 10%. The photometric method for determining the mass fraction of selenium using 3.3 ¢ -diaminobenzidine is arbitrary. 7.2 Photometric method using hydrazine sulfate 7.2.1 Method Essence The method is based on the photometric measurement of the optical density of a colored solution of elemental selenium obtained by the reduction of selenium compounds with hydrazine. 7.2.2 Apparatus, reagents and solutions: - spectrophotometer with a visible radiation limit and cuvettes with a thickness of the light-absorbing solution layer of 1 and 2 cm, type SF; - flask Kn-2-100-18 THS according to GOST 25336; - cylinder 3-50 according to GOST 1770; - flasks 2-100-2, 2-1000-2 according to GOST 1770; - pipettes with a capacity of 1, 2, 5, 10 and 20 cm 3; - sulfuric acid according to GOST 4204, chemically pure, diluted 1:2; - nitric acid according to GOST 4461, chemically pure, with a density of 1.4 g / cm 3; - carbon tetrachloride according to GOST 20288, chemically pure; - bromine according to GOST 4109, chemically pure; - a mixture of bromine and carbon tetrachloride, taken 2:3; - hydrazine sulfate according to GOST 5841, solution with a mass fraction of 1%; - microwave grade selenium; - the main solution with a selenium mass concentration of 1 mg / cm 3 is prepared according to GOST 4212 or as follows: 1 g of selenium is weighed, recording the weighing result in grams to the fourth decimal place, dissolved in 10 cm 3 of concentrated nitric acid, evaporated to dryness, two pour 10 cm 3 of water once, evaporate to dryness, transfer to a volumetric flask with a capacity of 1000 cm 3, add water to the mark and mix; - a working solution with a selenium mass concentration of 0.1 mg/cm 3 is prepared by 10-fold dilution of the stock solution with water. 7.2.3 Preparation for analysis To build a calibration graph in conical flasks with a capacity of 100 cm 3, pipette 0.5; 2; 4, 10; fifteen; 30 cm 3 working solution containing, respectively, 0.05; 0.2; 0.4; 1.0; 1.5; 3.0 mg of selenium, dilute with a solution of sulfuric acid to 40 cm 3 and add 1 cm 3 of a solution of hydrazine sulfate. The contents of the flask are gently heated to boiling and cooled under running cold water. The cooled solution is transferred to a volumetric flask with a capacity of 50 cm 3 and topped up with water to the mark. The optical density of solutions is measured with respect to water in a cuvette with a thickness of a light-absorbing layer of 2 cm at a wavelength of 600 nm. Based on the data obtained, a calibration graph is built, plotting the mass of selenium in milligrams on the abscissa axis, and the corresponding value of optical density on the ordinate axis. 7.2.4 Conducting an analysis 10 - 40 cm 3 of the solution (depending on the selenium content) prepared according to clause 6.1.4. are taken with a pipette, transferred to a conical flask with a capacity of 100 cm 3, 1 cm 3 of hydrazine sulfate is added. The contents of the flask are gently heated to boiling and cooled under running cold water. The resulting red color of the solution indicates the presence of selenium. The cooled solution is transferred to a volumetric flask with a capacity of 50 cm 3, topped up with water to the mark. Measurement of the optical density of the analyzed solution is carried out according to 7.2.3. The reference solution is a solution prepared under the same conditions and with the same amount of reagents, but without the analyzed solution. The mass of selenium in the analyzed solution in milligrams is found according to the calibration curve. 7.2.5 Results processing Mass fraction of selenium X 7,%, calculated according to the formula

(12)

Where t 1 - mass of selenium, found according to the calibration curve, mg; t- mass of sulfur sample, g; V

8 DETERMINATION OF THE MASS FRACTION OF IRON

8.1 Essence of the method The method is based on the photometric measurement of the optical density of the red iron complex (11) with o-phenanthroline at pH 3 - 4. 8.2 Equipment, reagents and solutions: - spectrophotometer of the SF type with a visible radiation limit and cuvettes with a thickness of the light-absorbing layer with a solution of 1 and 2 cm; - Laboratory resistance electric furnace of the SNOL type, providing a stable heating temperature (500 ± 10) ° С; - single-burner electric stove according to GOST 14919; - cylinder 1-10 according to GOST 1770; - flasks 2-50-2, 2-100-2, 2-500-2, 2-1000-2 according to GOST 1770; - pipettes with a capacity of 5, 10, 20, 25 and 50 cm3; - crucible H-20 according to GOST 19908; - nitric acid according to GOST 4461, chemically pure, diluted 1:1; - sulfuric acid according to GOST 4204, chemically pure diluted 1:2; - hydrochloric hydroxylamine according to GOST 5456, solution with a mass fraction of 10%; - sodium citrate according to GOST 22280, solution with a mass fraction of 25% and pH 3 - 5; - o-phenanthroline, h., solution with a mass fraction of 0.25%, obtained by dissolving in hot water (freshly prepared); - iron-ammonium alum, chemically pure; - the main solution with a mass concentration of iron of 0.1 mg / cm 3 is prepared as follows: 0.8635 g of iron ammonium alum is dissolved in water With by adding 4 cm 3 of concentrated sulfuric acid and topped up with water in a volumetric flask with a capacity of 1 dm 3 to the mark, a working solution with a mass concentration of iron of 0.01 mg/cm 3 is prepared by 10-fold dilution of the stock solution with water. 8.3 Preparation for analysis To construct a calibration curve, 0; 2.5; 5; ten; 12.5; fifteen; twenty; 25 and 30 cm 3 working solution containing, respectively, 0.000; 0.025; 0.050, 0.100, 0.125; 0.200; 0.250 and 0.300 mg of iron, diluted with water to 20 cm 3, add 1 cm 3 of hydroxylamine hydrochloride solution, stand for 5 minutes, then add 5 cm 3 of o-phenanthroline solution, 2 cm 3 of sodium citrate solution, add water to the mark and mix. After 15 minutes, the optical density of the solutions is measured with respect to water at a wavelength of 500 nm, in a cuvette with a thickness of the light-absorbing solution layer of 1 cm. optical density value. 8.4 Analysis (20 ± 1) g of sulfur is weighed, recording the weighing result in grams to the fourth decimal place, placed in a quartz crucible, carefully burned and the residue is calcined at (500 ± 10) ° C for 15 - 20 minutes. After cooling, the residue in the crucible is poured into 10 cm 3 of a nitric acid solution, heated for about 10 minutes, 2 cm 3 of a sulfuric acid solution are carefully added and evaporated until white fumes appear. Then cool and add 20 cm 3 of water. The resulting solution is filtered and quantitatively transferred into a volumetric flask with a capacity of 100 cm 3 . The solution is used to determine the mass fraction of manganese and copper. 5 cm 3 of an aliquot of the solution is taken with a pipette, placed in a volumetric flask with a capacity of 50 cm 3, diluted with water to 20 cm 3, 1 cm 3 of a solution of hydrochloric acid hydroxylamine is added, incubated for 5 minutes, then 5 cm 3 of a solution of o-phenanthroline, 2 cm 3 are added sodium citrate solution, add water to the mark, mix and after 15 min measure the optical density of the analyzed solution according to 8.3. The reference solution is a solution prepared under the same conditions and with the same amount of reagents, but without the analyzed product. The mass of iron in the analyzed solution in milligrams is found according to the calibration curve. 8.5 Processing of results The mass fraction of iron X 8,%, is calculated by the formula

(13)

Where t 1 - the mass of iron found according to the calibration curve, mg; t- mass of sulfur sample, g; V- the volume of the solution selected for analysis, cm 3 . The result of the analysis is taken as the arithmetic mean of the results of two parallel determinations, the relative discrepancy between which does not exceed the allowable discrepancy of 20%. Limits of permissible relative total error of the analysis result ± 10% of the average value. The photometric method for determining the mass fraction of iron using o-phenanthroline is arbitrary.

9 DETERMINATION OF THE MASS FRACTION OF MANGANESE

9.1 Photometric method using formaldoxime 9.1.1 Method Essence The method is based on the photometric measurement of the optical density of the brown-red complex formed by manganese with formaldoxime. 9.1.2 Apparatus, reagents and solutions: - Spectrophotometer type SF with a visible radiation limit and cuvettes with a thickness of the light-absorbing solution layer of 1 cm; - Laboratory resistance electric furnace of the SNOL type, providing a stable heating temperature (400 ± 10) ° С; - water bath or single-burner stove according to GOST 14919; - flasks 2-25-2, 2-1000-2 according to GOST 1770; - pipettes with a capacity of 1, 2, 5 and 10 cm 3; - cylinder 1-5 according to GOST 1770; - hydroxylamine hydrochloric acid according to GOST 5456; - formalin according to GOST 1625; solution with a mass fraction of 38% formaldehyde; - manganese sulfate according to GOST 435; - sulfuric acid according to GOST 4204, chemically pure, density 1.84 g/cm 3 ; - universal paper indicator; - formaldoxime (CH 2 NOH), 1 M solution, prepared as follows: 7.0 g of hydroxylamine hydrochloride is dissolved in a small amount of water in a volumetric flask with a capacity of 1 dm 3, 7.9 g of formalin are added and brought to the mark with water. The solution is stable for 1 month; - manganese, the main solution with a mass concentration of 1 mg / cm 3 is prepared as follows: 2.743 g of manganese sulfate, obtained from 5-aqueous manganese sulfate by drying at a temperature of (400 ± 10) ° C to constant weight, is dissolved in a volumetric flask with a capacity of 1 dm 3 in water with the addition of 1 cm 3 concentrated sulfuric acid and dilute with water to the mark; - manganese, a working solution with a mass concentration of manganese 0.01 mg/cm 3 is prepared by 100-fold dilution of the stock solution; - sodium hydroxide according to GOST 4328, concentration solution c (NaOH) = 1 mol / dm 3 (1 n.). 9.1.3 Preparation for analysis To build a calibration graph in volumetric flasks with a capacity of 25 cm 3 select 1.0 in turn; 2.0; 3.0; 4.0 and 5.0 cm 3 working solution containing, respectively, 0.01; 0.02, 0.03; 0.04 and 0.05 mg of manganese, add 2 cm 3 of formaldoxime solution and immediately neutralize in the presence of universal litmus paper with sodium hydroxide solution, add another 2 cm 3 of sodium hydroxide solution and add water to the mark and leave for 10 minutes. Then heated in a water bath at (70 ± 2) °C for 5 min, cooled to room temperature and measured the optical density of the solution at a wavelength of 455 nm, using water as a reference solution. Based on the results obtained, a calibration graph is built, plotting the mass of manganese in milligrams on the abscissa axis, and the corresponding optical density value on the ordinate axis. 9.1.4 Conducting an analysis In a volumetric flask with a capacity of 25 cm 3, 10 cm 3 of the solution prepared according to 8.4 is taken, 2 cm 3 of the formaldoxime solution are added, neutralized with sodium hydroxide solution in the presence of universal litmus paper and 2 cm 3 of sodium hydroxide solution are added and topped up with water to the mark, leaving for 10 min. Then heat in a water bath at (70 ± 2) °C for 5 min, cool to room temperature and measure the optical density of the analyzed solution relative to water according to 9.1.3. The mass of manganese in milligrams is determined from the calibration curve. 9.1.5 Results processing calculated according to the formula

(14)

Where t 1 - mass of manganese in the solution of the analyzed sample, found according to the calibration curve, mg; V t is the weight of the sulfur sample, g. The arithmetic mean of the results of two parallel determinations is taken as the result of the analysis, the relative discrepancy between which does not exceed the allowable discrepancy, equal to 15% of the average value. Limits of permissible relative total error of the analysis result ± 10%. The photometric method for determining the mass fraction of manganese using formaldoxime is arbitral. 9.2 Photometric method using potassium iodide 9.2.1 Method Essence The method is based on the photometric measurement of the optical density of the colored complex formed as a result of the oxidation of manganese (11) with potassium iodide. 9.2.2 Apparatus, reagents and solutions: - Spectrophotometer of the SF type with a visible radiation limit and cuvettes with a thickness of the light-absorbing solution layer of 1 and 2 cm; - single-burner electric stove according to GOST 14919; - flasks 2-25-2, 2-500-2 according to GOST 1770; - glass B-2-50 THS according to GOST 25336; - pipettes with a capacity of 2, 5, 10, 20, 50 cm 3; - nitric acid according to GOST 4461; chemically pure, diluted 1:1; - sulfuric acid according to GOST 4204; chemically pure, diluted 1:2; - orthophosphoric acid according to GOST 6552; chemically pure solution with a mass fraction of 85%; - potassium iodate (meta); - distilled water, twice distilled; - potassium permanganate according to GOST 20490-75; - the main solution with a mass concentration of manganese 0.1 mg/cm 3 is prepared as follows: 0.1440 g of potassium permanganate is weighed, recording the weighing result in grams to the fourth decimal place, dissolved in bidistilled water in a volumetric flask with a capacity of 500 cm 3 ; - a working solution with a mass concentration of manganese 0.01 mg/cm 3 is prepared by 10-fold dilution of the stock solution with water. To build a calibration graph in a glass with a capacity of 50 cm 3 pipette 2, 3, 4, 6 and 8 cm 3 of the working solution containing, respectively, 0.02; 0.03; 0.04; 0.06 and 0.08 mg of manganese, add 2 - 3 drops of phosphoric acid, 20 mg of potassium iodide, gently heat to a boil, boil for 1 - 2 minutes, cool, transfer to a volumetric flask with a capacity of 25 cm 3 and add water to the mark. The contents of the flask are mixed and the optical density of the solutions is measured with respect to water at a wavelength of 540 nm, using cuvettes with a thickness of the light absorbing layer of the solution of 2 cm. the corresponding optical density value. 9.2.4. Conducting an analysis 20 cm 3 of the solution prepared according to clause 8.4 are taken with a pipette, transferred to a glass with a capacity of 50 cm 3, 2-3 drops of phosphoric acid, 20 mg of potassium iodide are added, carefully heated to a boil, boiled for 1-2 minutes, cooled, transferred to a measuring a flask with a capacity of 25 cm 3, add water to the mark, mix and measure the optical density of the analyzed solution according to 9.2.3. The mass of manganese in the analyzed solution in milligrams is found according to the calibration curve. 9.2.5 Results processing Mass fraction of manganese X 9,%, find by formula

(15)

Where t 1 - mass of manganese, found according to the calibration curve, mg; t- mass of sulfur sample, g; V- the volume of the solution selected for analysis, cm 3 . The result of the analysis is taken as the arithmetic mean of the results of two parallel determinations, the relative discrepancy between which does not exceed the allowable discrepancy equal to 30% of the average value. Limits of permissible relative total error of the analysis result ± 15%.

10 DETERMINATION OF THE MASS FRACTION OF COPPER

10.1 Photometric method using lead diethyldithiocarbamate 10.1.1 Method Essence The method is based on the photometric measurement of the optical density of copper (II) chloroform extract with lead diethyldithiocarbamate 10.1.2 Equipment, reagents and solutions: - spectrophotometer with visible radiation limit and cuvettes with a light-absorbing solution layer thickness of 1 cm, SF-4A, SF-16 or SF-26; - flasks 2-10-2, 2-1000-2 according to GOST 1770; - funnel VD-1-100 XC according to GOST 25336; - cylinders 3-100, 1-500 according to GOST 1770; - pipettes with a capacity of 1, 5, 10, 20 and 50 cm 3; - absorbent cotton wool according to GOST 5556; - sulfuric acid according to GOST 4204, concentration solution c (H 2 SO 4) = 1 mol / dm 3 (1 n.); - indicator universal litmus paper; - lead diethyldithiocarbamate, a solution with a mass fraction of 0.25% in carbon tetrachloride or chloroform; - sodium N, N-diethyldithiocarbamate according to GOST 8864, solution with a mass fraction of 0.4%; - sodium tartrate or potassium tartrate; - lead acetic acid according to GOST 1027, solution with a mass fraction of 0.4%; - phenol red indicator, aqueous solution with a mass fraction of 0.1%; - aqueous ammonia according to GOST 3760, solution with a mass fraction of 5%; - chloroform, chemically pure, or carbon tetrachloride according to GOST 20288. Note - Reagents - sodium diethyldithiocarbamate, sodium or potassium tartrate, lead acetate, phenol red, aqueous ammonia in chloroform or carbon tetrachloride - are used in the absence of a ready-made solution of lead diethyldithiocarbamate with mass fractions of 0.025%, which is prepared as follows: 50 cm 3 of sodium diethyldithiocarbamate solution and 1 g of sodium (potassium) tartrate are weighed, recording the weighing result in grams to the fourth decimal place, placed in a separating funnel with a capacity of 1 dm 3, add 30 cm 3 lead acetate solution, stir and neutralize with aqueous ammonia solution in the presence of phenol red. The solution, together with the white precipitate in suspension, is shaken with 500 cm 3 of carbon tetrachloride or chloroform. The precipitate should dissolve. Then separate the aqueous layer, shake the non-aqueous layer with two portions of water, 100 cm 3 each. The non-aqueous layer is separated by filtration through absorbent cotton into a volumetric flask with a capacity of 1 dm 3 and topped up with chloroform or carbon tetrachloride to the mark. The solution is stable for 1 month. - copper sulphate according to GOST 4165; - the main solution with a mass concentration of copper 0.1 mg / cm 3 is prepared as follows: 0.3928 g of crystalline copper sulfate is weighed, recording the weighing result in grams to the fourth decimal place, dissolved in water with the addition of 2 cm 3 concentrated sulfuric acid in a volumetric flask with a capacity of 1 dm 3, add the solution with water to the mark and mix; - a working solution with a mass concentration of copper 0.001 mg/cm 3 is prepared by 100-fold dilution of the stock solution. 10.1.3 Preparation for analysis To build a calibration graph in separating funnels with a capacity of 100 cm 3 select 1.0 in turn; 5.0; 10.0; 15.0 and 20.0 cm 3 of the working solution containing, respectively, 0.001; 0.005; 0.010; 0.015; 0.020 mg of copper and topped up with water to a volume of 20 cm 3 . Adding a solution of sulfuric acid, bring the pH to 1 - 6 in the presence of universal litmus paper, add 5 cm 3 of a solution of lead diethyldithiocarbamate and shake for 2 minutes. Then the non-aqueous layer is separated, filtered through absorbent cotton into a volumetric flask with a capacity of 10 cm 3 . Then another 4 cm 3 of a solution of lead diethyldithiocarbamate is added, shaken for 1 min, the non-aqueous layer is separated, filtered through cotton wool and added to the solution in a volumetric flask, and topped up with chloroform or carbon tetrachloride to the mark. Optical density is measured at a wavelength of 435 nm using chloroform or carbon tetrachloride as a reference solution. On the basis of the results obtained, a calibration graph is built, plotting the mass of copper in milligrams on the abscissa axis, and the corresponding value of optical density on the ordinate axis. 10.1.4 Conducting an analysis 10 cm 3 of the analyzed sample solution, prepared according to clause 8.4, are placed in a separating funnel with a capacity of 100 cm 3, topped up with water to 20 cm 3. Adding a solution of sulfuric acid, bring the pH to 1 - 6 in the presence of universal litmus paper, add 5 cm 3 of a solution of lead diethyldithiocarbamate and shake for 2 minutes. The non-aqueous layer is separated by filtering through absorbent cotton into a 10 cm 3 volumetric flask. Then another 4 cm 3 of a solution of lead diethyldithiocarbamate is added, shaken for 1 min, the non-aqueous layer is separated, filtered through cotton wool, added to the solution in a volumetric flask, and topped up with chloroform or carbon tetrachloride to the mark. The optical density of the analyzed solution is measured according to 10.1.3, using as a reference solution a solution prepared under the same conditions and with the same amount of reagents, but without the analyzed solution. The mass of copper in the analyzed solution is found according to the calibration curve. 10.1.5 Results processing Mass fraction of copper X 10,%, find by formula

(16)

Where t 1 - mass of copper in the analyzed sample, found from the calibration curve, mg; V- the volume of the solution selected for analysis, cm 3 ; t is the weight of the sulfur sample, g. The arithmetic mean of the results of two parallel determinations is taken as the result of the analysis, the relative discrepancy between which does not exceed the allowable discrepancy, equal to 15% of the average value. Limits of permissible relative total error of the analysis result ± 10%. Determination of the mass fraction of copper using lead diethyldithiocarbamate is an arbitration method. 10.2 Photometric method using sodium diethyldithiocarbamate 10.2.1 Method Essence The method is based on: photometric measurement of the optical density of an extract of copper (II) with sodium diethyldithiocarbamate, colored yellow. 10.2.2 Equipment, reagents and solutions:- a spectrophotometer with a visible radiation limit and cuvettes with a thickness of the light-absorbing solution layer of 1 cm, type SF; - flasks 2-500-2, 2-1000-2 according to GOST 1770; - funnels VD-1-50 XC according to GOST 25336; - cylinder 1-5 according to GOST 1770; - pipettes with a capacity of 1, 2, 5 and 10 cm 3; - laboratory filter paper according to GOST 12026; - nitric acid according to GOST 4461, chemically pure, diluted 1:1; - sulfuric acid according to GOST 4204-77, chemically pure, diluted 1:2; - chloroform, chemically pure; - ammonia according to GOST 3760-79, chemically pure, diluted 1:1; - disodium salt of ethylenediamine-N, N, N ¢ N ¢ -tetraacetic acid, 2-aqueous (trilon B) according to GOST 10652-73, chemically pure, solution with a mass fraction of 10%; - sodium N, N ¢ -diethyldithiocarbamate according to GOST 8864-71, solution with a mass fraction of 1% (freshly prepared); - disubstituted ammonium citrate, solution with a mass fraction of 25%; - the main solution with a mass concentration of copper 0.1 mg/cm 3 is prepared according to 10.1.2; - a working solution with a mass concentration of copper of 0.01 mg/cm is prepared by 10-fold dilution of the stock solution. 10.2.3 Preparation for analysis To build a calibration graph in separating funnels with a capacity of 50 cm 3, pipette 1, 2, 4, 6, 8 cm 3 of a working solution containing, respectively, 0.01; 0.02; 0.04; 0.06; 0.08 mg of copper and carefully neutralized dropwise with an ammonia solution, add 1 cm 3 of a solution of Trilon B, 5 cm 3 of a solution of ammonium citrate, 1 cm 3 of a solution of sodium diethyldithiocarbamate and 10 cm 3 of chloroform. The resulting solution is shaken for 2 minutes. After separation of the layers, the chloroform layer is filtered through a dry paper filter and the optical density of the colored extract is measured at a wavelength of 435 nm, relative to the solution prepared under the same conditions and with the same amount of reagents, but without the working solution of copper. Based on the data obtained, a calibration graph is built, plotting the mass of copper in milligrams on the abscissa axis, and the corresponding optical density value on the ordinate axis. 10.2.4 Conducting an analysis 10 cm 3 of the solution prepared according to 8.4 is pipetted into a separating funnel with a capacity of 50 cm 3 and then analyzed according to 10.2.3. The reference solution is a solution prepared under the same conditions and with the same amount of reagents, but without the analyzed solution. The mass of copper in the analyzed solution is found according to the calibration curve. 10.2.5 Results processing Mass fraction of copper X 10,%, calculated according to the formula

(17)

Where t 1 - mass of copper in the analyzed sample, found from the calibration curve, mg; t- mass of sulfur sample, g; V- the volume of the solution selected for analysis, cm 3 . The result of the analysis is taken as the arithmetic mean of the results of two parallel determinations, the relative discrepancy between which should not exceed the allowable discrepancy equal to 25% of the average value. Limits of permissible relative total error of the analysis result ± 15%.

11 DETERMINATION OF THE MASS FRACTION OF IRON, MANGANESE AND COPPER

11.1 Essence of the method The method is based on photographing the spectra of the analyzed samples and reference samples and determining the mass fraction of iron, manganese and copper according to the calibration curve. 11.2 Apparatus, reagents and solutions: - ISP-30 or ISP-28 quartz spectrograph with a single-lens illumination system; - alternating current arc generator DG-2 in the low-voltage spark mode; - microphotometer IFO-451 (MF-2); - spectrum projector SPP-1; - device for sharpening carbon electrodes; - agate or chalcedonic mortars, 90 mm in diameter; - spectrographic photographic plates of the "micro" type with a sensitivity of 90 units; - infrared lamp; - carbon electrodes special purity grade 7-4 or C-1; lower electrode with a crater 4 mm in diameter, 4 mm deep; the upper electrode is sharpened on a truncated cone with a platform of 2 mm; - iron oxide; - copper (II) oxide according to GOST 16539; - manganese (IV) oxide according to GOST 4470; - sulfur wasps. ch. 16-5; - developer and fixer; - technical ethyl alcohol according to GOST 18300, distilled. 11.3 Preparation for analysis The main sample of sulfur with a mass fraction of iron, manganese and copper, 10% of each element, is prepared as follows: 6.027 g of os.p. sulfur. mixed with 1.429 g of iron oxide, 1.253 g of copper oxide and 1.291 g of manganese oxide. The mixture is ground in an agate mortar under a layer of alcohol for 1.5 - 2 hours, then dried under an infrared lamp at (80 ± 2) ° C to constant weight. Reference samples are prepared from the main sample by successive dilution of pure sulfur. Mass fraction of iron, manganese and copper in the samples, %: the first comparison sample - 1 each; the second sample of comparison - 0.3; the third comparison sample - 0.1 each; the fourth comparison sample - 0.03 each; the fifth comparison sample - 0.01 each; the sixth comparison sample - 0.003 each; the seventh comparison sample - 0.001 each. Comparison samples, like the main sample, are prepared in an agate mortar under a layer of alcohol. Samples are stored in plastic containers with ground stoppers. Reference samples are introduced into the hole of the lower electrode using a dosing plate made of organic glass. A low-voltage spark is ignited between the electrodes from a DG-2 generator with a current of 6 A, the distance between the electrodes is 2 mm, the exposure is 25 s. The spectra of reference samples are photographed three times with a spectrograph at a slit width of 0.01 mm. On the obtained spectrograms, the blackening of the analytical lines and the background near the analytical lines is measured according to Table 5. Table 5 Based on the results of photometry of the spectra of the comparison samples, calibration graphs are built in the coordinates - mass fraction (of iron, manganese and copper) - blackening of the analytical lines. 11.4 Analysis The sulfur sample to be analyzed is crushed under alcohol to the same size as the reference samples, and the blackening of the analytical lines is measured according to 11.3. According to the results of photometry of the spectra according to the calibration curve, the mass fraction of iron, manganese and copper in the analyzed sample is found. The result of the analysis is taken as the arithmetic mean of the results of two parallel determinations, the relative allowable discrepancy between which should not exceed the allowable discrepancy equal to 30% of the average value. Limits of permissible relative total error of the analysis result ± 15%. The reproducibility of the spectral method for determining the mass fraction of iron, manganese and copper in sulfur is characterized by the mean square error of ± 15%.

12 DETERMINATION OF THE MASS FRACTION OF WATER

12.1 Essence of the method The method is based on weight determination of weight loss as a result of drying at (70 ± 2) °C. 12.2 Equipment: - SNOL type drying cabinet providing a stable heating temperature (70 ± 2) °C; - a cup of ChBN-2 according to GOST 25336. 12.3 Analysis (100 ± 1) g of lump sulfur and (10 ± 1) g of ground sulfur are weighed in cups dried to constant weight, dried in an oven at a temperature of (70 ± 2) ° C to constant weight and weighed. The results of all weighings in grams are recorded to the third decimal place. 12.4 Processing of results Mass fraction of water X 11,%, calculated according to the formula

Where t- mass of sulfur sample, g; t 1 - mass of the residue after drying, g. The arithmetic mean of the results of two parallel determinations is taken as the result of the analysis, the absolute allowable discrepancy between which, as well as the absolute total error of the analysis results, does not exceed the values \u200b\u200bspecified in Table 6. Table 6 In percent

13 DETERMINATION OF PARTICULATION COMPOSITION

13.1 Essence of the method The method is based on the weight determination of fractions , obtained by screening samples on sieves. 13.2. Equipment and reagents: - sieves with a shell 75 mm in diameter, 45 mm high, mesh 014 N and 0071 N according to GOST 6613; - flute brush (No. 18 from horsehair); - drying cabinet type SNOL, providing a stable heating temperature (70 ± 2) ° С; - cup CH according to GOST 25336; - a cup of CCC according to GOST 25336. 13.3 Carrying out the test (20 ± 1) g of ground sulfur dried at (20 ± 2) ° С is transferred to a sieve with a 014 N mesh, a sieve with a 0071 H mesh is placed under it, and then a tray and sieving is carried out within 20 min. Then open the lid, crush the lumps of sulfur on the sieves with a soft brush and remove the sulfur from the back of the sieve into the next sieve or tray. Sieving is repeated until the residue on the sieves ceases to decrease. Note - In the absence of an apparatus for mechanical sieving, sieving is carried out manually on the same sieves, wiping the sulfur on the sieve with a brush. At the end of the sieving, the residue is transferred with a brush into a weighed cup and weighed. The results of all weighings in grams are recorded to the third decimal place. 13.4 Processing of results Residue on sieve X 12 % calculated according to the formula

Where t- mass of sulfur sample, g; t 1 - mass of the residue on the sieve, g. The arithmetic mean of the results of two parallel determinations is taken as the result of the analysis, the relative discrepancy between which does not exceed the allowable discrepancy, equal to 10% of the average value. Limits of permissible relative total error of the analysis result ± 7%.

INFORMATION DATA

REFERENCE REGULATIONS AND TECHNICAL DOCUMENTS

	Number of paragraph, subparagraph
GOST 127.3-93	1.8
GOST 435-77	9.1.2
GOST 1027-67	6.1.2 ; 10.1.2
GOST 1625-89	9.1.2
GOST 1770-74	4.2 ; 5.4.2 ; 6.1.2 ; 6.3.2 ; 7.1.2 ; 7.2.2 ; 8.2 ; 9.1.2 ; 9.2.2 ; 10.1.2 ; 10.2.2
GOST 1973-77	6.1.2 ; 6.3.2
GOST 2053-77	5.4.2
GOST 2603-79	5.2.2
GOST 3118-77	6.1.2
GOST 3760-79	7.1.2 ; 10.1.2 ; 10.2.2
GOST 3765-78	6.3.2
GOST 3773-72	7.1.2
GOST 3776-78	5.1.2
GOST 4109-79	6.1.2 ; 7.2.2
GOST 4165-78	10.1.2
GOST 4166-76	5.1.2
GOST 4171-76	5.1.2
GOST 4204-77	5.1.2 ; 6.1.2 ; 6.3.2 ; 7.1.2 ; 7.2.2 ; 8.2 ; 9.1.2 ; 9.2.2 ; 10.1.2 ; 10.2.2
GOST 4212-76	1.6 ; 6.1.2 ; 7.1.2 ; 7.2.2
GOST 4232-74	6.1.2
GOST 4328-77	4.2
GOST 4461-77	6.1.2 ; 6.3.2 ; 7.2.2 ; 8.2 ; 9.2.2 ; 10.2.2
GOST 4470-79	11.2
GOST 4517-87	1.6 ; 4.2 ; 6.1.2
GOST 4530-76	5.1.2
GOST 4919.1-77	1.6
GOST 4919.2-77	1.6
GOST 5456-79	8.2: 9.1.2
GOST 5556-81	5.1.2 ; 7.1.2 ; 9.1.2 ; 10.1.2
GOST 5789-78	7.1.2
GOST 5841-74	6.3.2 ; 7.2.2
GOST 5848-73	7.1.2
GOST 5955-75	5.2.2
GOST 6613-86	5.2.2 ; 6.2.2 ; 13.2
GOST 6552-80	9.2.2
GOST 6709-72	1.4
GOST 7172-76	6.3.2
GOST 7328-82	1.4
GOST 7995-80	5.1.2
GOST 8864-71	10.1.2 ; 10.2.2
GOST 9147-80	5.1.2 ; 5.4.2 ; 6.3.2
GOST 10485-75	6.1.2
GOST 10652-73	7.1.2 ; 10.2.2
GOST 12026-76	4.2 ; 5.4.2 ; 6.3.2 ; 10.2.2
GOST 13045-81	5.1.2
GOST 13647-78	6.1.2
GOST 14919-83	3.2 ; 5.4.2 ; 6.1.2 ; 6.3.2: 8.2 ; 9.1.2 ; 9.2.2
GOST 16539-79	5.1.2 ; 11.2
GOST 18300-87	4.2 ; 5.4.2 ; 6.2.2 ; 6.3.2 ; 11.2
GOST 19908-90	3.2 ; 5.3.2 ; 6.3.2 ; 8.2
GOST 20288-74	5.4.2 ; 6.1.2 ; 7.2.2 ; 10.1.2
GOST 20490-75	5.1.2 ; 9.2.2
GOST 22280-76	8.2
GOST 24104-88	1.4
GOST 24363-80	4.2 ; 5.1.2
GOST 25336-82	3.2 ; 4.2 ; 5.1.2 ; 5.2.2 ; 5.3.2 ; 5.4.2 ; 6.1.2 ; 6.2.2 ; 6.3.2 ; 7.1.2 ; 7.2.2 ; 9.2.2 ; 10.1.2 ; 10.2.2 ; 12.2 ; 13.2
GOST 25794.1-83	1.6

INTERSTATE STANDARD

SULFUR TECHNICAL

SAMPLING AND PREPARATION

Official edition

MKZH1 SUDAISCHVINNY SOVKG BUT STANDARDIZATION. METROLOGY AND CERTIFICATION Minsk

GOST 127.3-M

Foreword

1 DEVELOPED by Sulfur Industry R&D Pietist with Pilot Plant, Ukraine

INTRODUCED by the Technical Secretariat of the Interstate Council for Standardization, Metrology and Certification

2 ADOPTED by the Interstate Council for Standardization, Metrology and Certification on October 21, 1993 (order N? I to protocol No. 4-93)

3 By the Decree of the Committee of the Russian Federation for Standardization, Metrology and Certification dated March 21, 1996 No. 200, the interstate standard GOST 127.3-93 was put into effect directly as a state standard from January 1, 1997.

3.2 Sample preparation equipment:

Dividers are mechanical, providing uniform division of the combined sample;

Sheet for cutting samples;

Drying cabinet, providing a stable temperature heated (70 ± 2) 'C;

Mechanical or manual grinders that provide grinding of a sample with a particle size of not more than 0.16 mm;

Scales with a weighing error of ±10 g;

Sample receivers for combining samples;

Sieves with grids 016 according to GOST 6613.

4 SAMPLING

4.1 Sampling of code sulfur

4.1.1 Sampling of lump sulfur is carried out from vehicles (gondola cars, barges).

It is allowed to take sulfur samples during loading (unloading gondola cars, barges), from a stack prepared for shipment, during the formation of a stack during filling.

4.1.2. From vehicles, point samples are taken with a scoop at points evenly distributed over the surface of the mass being tested.

If there are lumps of sulfur larger than 50 mm at the indicated points, pieces of no more than 25 mm in size are beaten off from them with a hammer and a scoop is filled with these pieces.

4.1.3 The mass of an incremental sample must be at least 0.5 kg.

4.1 4 The minimum number of increments N is calculated by the formula

l g \u003d 0.075-kVa / .

where A/ is the mass of the batch being tested, t;

V - coefficient of variation of the mass fraction of one in the components of sulfur impurities (ash, organic acids or acids). %

The coefficient of variation is calculated by the formula

GOST 127.3-9.1 p. four

where o is the standard deviation of the signs of one of the impurity components (mass fraction of ash, organic substances or acids),%;

X - arithmetic mean value of one of the components (mass fraction of ash, organic substances or acids),%.

Notes

1 Component for which the coefficient of variation is set. determines each enterprise on the basis of actual data of quality indicators and less than a monthly output

2 If it is difficult or impossible to determine the coefficient of variation, at least one point sample from every 10 g of sulfur is provided.

4.1.5 Samples are taken from the stack after loosening as follows:

the entire surface of the stack (or part of it) is divided into squares, the number of which should be equal to the number of incremental samples determined in paragraph 4.1.4. Spot samples are taken from the middle of the square according to 4.1.2.

4.1.6 When loading (unloading) sulfur in vehicles selection is made:

from the conveyor belt (conveyor) with a mechanical sampler or manually with a scoop - crossing over the entire width with a sampling period that ensures the minimum number of incremental samples, calculated according to 4.1.4.

4.1.7 When forming a stack during pouring, sampling is carried out by automatic or mechanical intersection of the jet with a sampling period that ensures the minimum number of point samples.

4.2 Sampling liquid sulfur

4.2.1 Point samples of liquid sulfur are taken by a sampler from filled tanks or when filling and draining tanks.

It is allowed to take point samples from filled storage tanks (pits).

4.2.2 From the filled tanks, storage tanks (pits), point P | x) would be taken from three layers: one sample from the bottom, three samples from the middle, one from the top.

S. 5 GOST 127.3-M

4.2.3 In the case of flooding, flooding, and sterilization, incremental samples are taken by aromatic or mechanical intersection of the jet with a sampling period that ensures that the minimum number of incremental samples calculated according to 4.1.4 is obtained.

4.2.4 The mass of the incremental sample must be at least 0.2 kg.

4.3 Sampling of ground sulfur

4.3.1 Point samples of ground sulfur or bags are taken with a probe, immersing 4/5 of the depth of the bag,

4.3.2 Incremental samples from the container;! is taken with a probe from five points in the directions of four diagonals to the corners of the container and along its center from top to bottom.

4.3.3 The mass of the incremental sample must be at least 0.05 kg.

5 SAMPLE PREPARATION

5.1 Point samples of lump sulfur are combined together, thoroughly mixed, at least 0.2 kg is isolated to determine the mass fraction of water. The rest of the method of successive reduction and grinding is brought to an average sample. Pass through a 0.16 mm sieve. Lumps that have not passed through a sieve are ground until completely sieved.

5.2 Point samples of ground sulfur are combined together, thoroughly mixed, separating at least 50 g of sulfur to determine the mass fraction of water. The rest is reduced by quartering to obtain an average sample.

5.3 Point samples of sulfur vein are combined together, mixed and, after solidification, by successive grinding and reduction, bring to medium P|yuba. Pass through a 0.16 mm sieve. Lumps that have not passed through a sieve are ground until completely sieved.

5.4 It is allowed not to sift the sample, provided that equipment is used that ensures a grinding fineness of less than 0.16 mm.

5.5 The mass of the average sample according to paragraphs. 5.1-5.3 not less than 0.5 kg.

5.6 The average sample is divided into two equal parts: a sample for chemical analysis and arbitration trials;

Samples of lump and ground sulfur intended for hnmichss-

whom analysis, dried at a temperature of (70 ± 2) * C to constant weight.

Having placed the samples" in sealed bags or jars and stick a label containing the following data:

Business name;

Assignment of the sample (for chemical analysis, arbitration sample);

Product name;

Batch number;

date and place of sampling;

The mass of the party;

Surname of the sampler.

It is allowed to determine the quality indicators of sulfur without preliminary drying of the sample with conversion to dry matter.

c.7 IWT 127.3-93

AND INFORMATION DATA

REFERENCE REGULATIONS AND TECHNICAL DOCUMENTS

(Khishm/ti NTD. in tuKfiuft g.pi uiwi		liviitp ggppt piaegtg"
GOS G 12.0.003-74
GOST 12.1.005-IH
GOST 12 2 061-I 1
GOSG 12 3.009-76

GOST 127.1-93
Sulfur for industrial use. Specifications
OKP 21 1221
OKS 71.060
21 1222 ________________________
Introduction date 1997-01-01
This standard applies to technical natural sulfur obtained from native sulfur and polymetallic sulfide ores, and technical gas sulfur obtained during the purification of natural and coke oven gases, as well as off-gases from oil and shale processing.
Technical sulfur is used for the production of sulfuric acid, carbon disulfide, dyes, in the pulp and paper, textile and other industries and exports.
The requirements of this standard are mandatory.
1 TECHNICAL REQUIREMENTS
1.1 Technical sulfur must be produced in accordance with the requirements of this standard according to the technological regulations approved in the prescribed manner.
1.2 Technical sulfur is produced liquid and lumpy.
1.3 Technical sulfur codes according to OKP are given in the appendix.
1.4 In terms of physical and chemical parameters, technical sulfur must comply with the standards specified in Table 1.

C.2 GOST 127.1-93
Table L
Name of indicator
Norm
Grade 9998
Grade 9995
Grade 9990

Grade 9920
1 Mass fraction of sulfur, %, not less than
99, 98
99, 95
99, 90

99, 20
2 Mass fraction of ash, %, no more
0, 02
0, 03
0, 05

0, 4
3 Mass fraction of organic substances, %, no more
0, 01
0, 03
0, 06

0, 5
4 Mass fraction of acids in
in terms of sulfuric acid, %, no more
0, 0015
0, 003
0, 004

0, 02
5 Mass fraction of arsenic, %, no more
0, 0000
0, 0000
0, 000

0, 03
6 Mass fraction of selenium, %, no more
0, 000
0, 000
0, 000

0, 04
7 Mass fraction of water, %, no more
0, 2
0, 2
0, 2

1, 0
8 Mechanical pollution (paper, wood, sand, etc.)
ht
: allowed
Notes
1 Norms for indicators 1-6 are given in terms of dry matter;
2 Mass fraction of ash for liquid sulfur grade 9998 should be no more than 0.00S%, grades 9995 and 9990 no more than 0.01%;
3 The mass fraction of arsenic and selenium in natural sulfur obtained from native sulfur ores and in gaseous sulfur obtained during the purification of natural gases, as well as waste gases from oil refining, is not determined. In sulfur of technical gas grade 9920, produced by coke-chemical enterprises, the mass fraction of arsenic is allowed, by agreement with the consumer, not more than 0.05%;
4 The mass fraction of selenium in sulfur intended for the pulp and paper industry should be no more than 0.000%;
5 The mass fraction of water in liquid sulfur is not standardized. In lump sulfur, it is allowed to increase the mass fraction of water up to 2% with the conversion of the actual mass of the batch to the normalized humidity;
6 Lump sulfur intended for export should not contain pieces larger than 200 mm.
1.5 Indicators for items 4-6 of the table are determined at the request of the consumer or the controlling organization.
1.6 An example of a symbol when ordering: Technical gas liquid sulfur, grade 9998, GOST 127.1-93.
2
4

GOST 127.1-93 C.Z
2 SAFETY REQUIREMENTS
2.1 Sulfur is flammable. Airborne dust is fire and explosion hazard. The lower concentration limit of flame propagation (ignition) - 17 g/m 3 ; self-ignition temperature - 190 "C according to GOST 12.1.041.
Hydrogen sulfide released from liquid sulfur explodes at a volume concentration of 4.3 to 45%; self-ignition temperature - 260 °C.
2.2 Sulfur belongs to the 4th hazard class (GOST 12.1.005). Sulfur causes inflammation of the mucous membranes of the eyes and upper
respiratory tract, skin irritation, gastrointestinal disease; does not have cumulative properties.
Hydrogen sulfide is a poison that has a strong effect on the central nervous system.
Sulfur dioxide, which is formed during the combustion of sulfur, irritates the mucous membranes of the nose and upper respiratory tract.
Maximum permissible mass concentrations in the air of the working area: sulfur - 6 mg/m 3 ; sulfurous anhydride - 10 mg / m 3; hydrogen sulfide - 10 mg / m 3.
2.3 Production facilities and laboratories in which work with technical sulfur is carried out must be equipped with supply and exhaust mechanical ventilation that ensures compliance with the maximum permissible concentrations of harmful substances in the air of the working area.
Air control of the working area must be carried out in accordance with the requirements of GOST 12.1.005 according to the methods approved by the Ministry of Health.
2.4 All workers must be provided with special clothing and personal protective equipment in accordance with GOST 12.4.011.
3 ACCEPTANCE RULES
3.1 Sulfur is subjected to acceptance tests.
3.2 Sulfur is accepted in batches. A batch is considered to be the amount of sulfur shipped to one address and accompanied by one quality document.
When transporting water transport each transport unit (barge, ship, tanker) is taken as a batch of sulfur.
2-953
5
3

C.4 GOST 127.1-93
3.3 The quality document must contain the following data: - the name of the manufacturer and (or) its commercial
sign;
- name and grade of the product;
- batch number and date of shipment;
- numbers of railway cars or other vehicles (for direct deliveries);
- the results of the tests carried out or confirmation of the conformity of the product to the requirements of this standard;
- net weight;
- danger sign 4a and classification code 4133 according to GOST 19433;
- UN serial number: for lump sulfur - 1350; for liquid - 2448;
- signature and stamp of the technical control department;
- designation of this standard.
3.4 To control the quality of lump and liquid sulfur, samples are taken from every fourth wagon (tank) of the controlled batch, but not less than from three wagons (tanks).
When sending sulfur in the amount of less than three transport units, samples are taken from each transport unit.
When sending sulfur by water transport, it is allowed to take samples during shipment (unloading) of barges.
4 TEST METHODS
4.1 Sampling and preparation of samples is carried out in accordance with GOST 127.3.
4.2 Tests are carried out in accordance with GOST 127.2.
4.3 The presence of mechanical impurities is determined visually.
5 TRANSPORT AND STORAGE
5.1 Lump sulfur is transported in bulk in gondola cars with lower hatches, as well as by road and water transport. By agreement with the consumer, it is allowed to transport sulfur in covered wagons. The doors of the wagons must be closed with safety shields.
It is not allowed to load sulfur into contaminated vehicles.
4
6

GOST 127.1-93 С.5
Liquid sulfur is transported in special heated railway tanks used only for liquid sulfur transportation. Transportation is carried out in accordance with the instructions for the operation and maintenance of railway tanks.
5.2 Transportation of sulfur intended for export is carried out in accordance with the requirements of this standard or contract.
5.3 Lump sulfur is stored under a canopy or in open areas.
In order to avoid pollution of sulfur, the sites should be provided with industrial sewerage.
Liquid sulfur is stored in special insulated tanks equipped with heating and pumping devices, as well as measuring instruments and exhaust pipes.
Tanks should have the inscription "LIQUID SULFUR".
6 MANUFACTURER WARRANTY
The manufacturer guarantees the compliance of technical sulfur with the requirements of this standard, subject to the conditions of transportation and storage.
Warranty period of storage of technical sulfur - one year from the date of shipment.
2*
7
5

C.6 GOST 127.1-93
APPENDIX
(reference)
OKP codes for technical sulfur
Product name
OKP code
CZK
Sulfur technical natural
21 1221
Sulfur technical natural lump
21 1221 0100

06
grade 9995
21 1221 IT

04
grade 9990
21 1221 0120

02
grade 9950
21 1221 0130

00
grade 9920
21 1221 0140

09
Sulfur technical natural liquid
21 1221 1000

05
grade 9995
21 1221 1010

03
grade 9990
21 1221 1020

01
Sulfur technical gas
21 1222
Sulfur technical gas lump
21 1222 0100

01
grade 9998
21 1222 IT

10
grade 9995
21 1222 0120

08
grade 9990
21 1222 0130

06
grade 9950
21 1222 0140

04
grade 9920
21 1222 0150

02
Sulfur technical gas liquid
21 1222 1000

00
grade 9998
21 1222 1010

09
grade 9995
21 1222 1020

07
grade 9990
21 1222 1030

HE
6
X

GOST 127.1-93 C.7
REFERENCE REGULATIONS AND TECHNICAL DOCUMENTS
The designation of the NTD to which the link is given
Number of paragraph, subparagraph
GOST
12.1.005-88
2.2; 2.3
gost
12.1.041-83
2.1
gost
12.4.011-89
2.4
gost
127.2-93
4.2
gost
127.3-93
4.3
gost
19433-88
3.3
9
7

GOST 127.2-93 INTERSTATE STANDARD
SULFUR TECHNICAL
TEST METHODS

GOST 127.2-93 Preface
1 DEVELOPED by the Research and Design Institute of the Sulfur Industry with a Pilot Plant, Ukraine
INTRODUCED by the Technical Secretariat of the Interstate Council for Standardization, Metrology and Certification
2 ADOPTED by the Interstate Council for Standardization, Metrology and Certification on October 21, 1993 (Order No. 1 to Protocol No. 4-93)
Voted to accept:
State name
Name of the national standards body
Republic of Armenia
Armstate standard
Republic of Belarus
Belstandard
The Republic of Kazakhstan
State Standard of the Republic of Kazakhstan
The Republic of Moldova
Moldovastandard
Russian Federation
Gosstandart of Russia
Turkmenistan
Turkmenglavstate inspection
The Republic of Uzbekistan
Uzgosstandart
Ukraine
State Standard of Ukraine
3 By the Decree of the Committee of the Russian Federation for Standardization, Metrology and Certification No. 199 dated March 21, 1996, the interstate standard GOST 127.2-93 was put into effect directly as a state standard from January 1, 1997.
4 INSTEAD OF GOST 127-76 (in terms of analysis methods)
© IPK Standards Publishing House, 1996
This standard cannot be fully or partially reproduced, replicated and distributed as an official publication on the territory of the Russian Federation without the permission of the State Standard of Russia
1 1 v- " " > II

GOST 127.1 93 sulfur technical specifications.

"TECHNICAL SULFUR. TEST METHODS. GOST 127.2-93" (approved by the State Standard of the USSR of 10.21.93, protocol N 4-93)

1 TECHNICAL REQUIREMENTS

2 SAFETY REQUIREMENTS

3 ACCEPTANCE RULES

4 METHODS OF ANALYSIS

5 TRANSPORT AND STORAGE

1 GENERAL REQUIREMENTS

2 DETERMINATION OF THE MASS FRACTION OF SULFUR

3 DETERMINATION OF THE MASS FRACTION OF ASH

4 DETERMINATION OF THE MASS FRACTION OF ACIDS IN CONVERSION TO SULFURIC ACID

5 DETERMINATION OF THE MASS FRACTION OF ORGANIC SUBSTANCES

6 DETERMINATION OF THE MASS FRACTION OF ARSENIC

7 DETERMINATION OF THE MASS FRACTION OF SELENIUM

8 DETERMINATION OF THE MASS FRACTION OF IRON

9 DETERMINATION OF THE MASS FRACTION OF MANGANESE

10 DETERMINATION OF THE MASS FRACTION OF COPPER

11 DETERMINATION OF THE MASS FRACTION OF IRON, MANGANESE AND COPPER

12 DETERMINATION OF THE MASS FRACTION OF WATER

13 DETERMINATION OF PARTICULATION COMPOSITION

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"TECHNICAL SULFUR. ​​TEST METHODS. GOST 127.2-93" (approved by the State Standard of the USSR of 10.21.93, protocol N 4-93)

1 GENERAL REQUIREMENTS

2 DETERMINATION OF THE MASS FRACTION OF SULFUR

3 DETERMINATION OF THE MASS FRACTION OF ASH

4 DETERMINATION OF THE MASS FRACTION OF ACIDS IN CONVERSION TO SULFURIC ACID

5 DETERMINATION OF THE MASS FRACTION OF ORGANIC SUBSTANCES

6 DETERMINATION OF THE MASS FRACTION OF ARSENIC

7 DETERMINATION OF THE MASS FRACTION OF SELENIUM

8 DETERMINATION OF THE MASS FRACTION OF IRON

9 DETERMINATION OF THE MASS FRACTION OF MANGANESE

10 DETERMINATION OF THE MASS FRACTION OF COPPER

11 DETERMINATION OF THE MASS FRACTION OF IRON, MANGANESE AND COPPER

12 DETERMINATION OF THE MASS FRACTION OF WATER

13 DETERMINATION OF PARTICULATION COMPOSITION

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"TECHNICAL SULFUR. TEST METHODS. GOST 127.2-93" (approved by the State Standard of the USSR of 10.21.93, protocol N 4-93)