GOST 1293.5-83

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  ГОСТ 1293.5-83

GOST 1293.5−83 lead-antimony Alloys. Methods for determination of zinc and copper (with Amendments No. 1, 2)

GOST 1293.5−83*
______________________
* The designation of the standard.
Changed the wording, Rev. N 2.

Group B59

STATE STANDARD OF THE USSR

LEAD-ANTIMONY ALLOYS

Methods for determination of zinc and copper

Lead-antimony alloys. Methods for the determination of zinc and copper

AXTU 1709*
________________

* Changed the wording, Rev. N 1.

Valid from 01.07.83
prior to 01.07.88*
_______________________________
* Expiration removed by Protocol No. 7−95
The interstate Council for standardization,
Metrology and certification (I & C N 11, 1995). -
Note the manufacturer’s database.

DEVELOPED by the Ministry of nonferrous metallurgy of the USSR

PERFORMERS

A. P. Sychev, M. G. Sun, L. I. Maksay, R. D. Kogan

INTRODUCED by the Ministry of nonferrous metallurgy of the USSR

Member Of The Board Of A. P. Snurnikov

APPROVED AND put INTO EFFECT by Decision of the USSR State Committee on standards of February 8, 1983 N 704

REPLACE GOST 1293.5−74

MADE: the Change in N 1, approved and put into effect by the Decree of the USSR State Committee for standards from 20.11.87 N 4205 from 01.07.88, Change No. 2 adopted by the Interstate Council for standardization, Metrology and certification (minutes N 13 dated 28.05.98). The state developer of Kazakhstan. By the resolution of Gosstandart of Russia from 11.04.2001 N 173-St introduced on the territory of the Russian Federation from 01.01.2002

Change N 1, 2 made by the manufacturer of the database in the text IUS N 2, 1988, ICS # 7, 2001

This standard establishes the atomic absorption method for the determination of zinc and copper when the mass fraction of zinc from 0.0005 to 0.05%, copper 0.002−0.6% polarographic method for the determination of zinc and copper when the mass fraction of zinc from 0.0005 to 0.05%, copper of 0.001 to 0.3% of lead-antimony alloys.

(Changed edition, Rev. N 2).

1. GENERAL REQUIREMENTS

1.1. General requirements for methods of analysis GOST 1293.0−83.

2. ATOMIC ABSORPTION METHOD FOR THE DETERMINATION OF ZINC AND COPPER

______________
* The name of the section. Changed the wording, Rev. N 2.

2.1. The essence of the method

The method is based on dissolving the sample in a mixture of nitric and tartaric acids, the spraying solutions in the air-acetylene flame and measuring the absorption lines of 213,8 nm zinc and copper 324,8 nm.

(Changed edition, Rev. N 2).

2.2. Apparatus, reagents and solutions

Atomic absorption spectrophotometer of any brand.

Air, compressed under a pressure of 2·10-6·10PA (2−6 ATM.) depending on the equipment.

Acetylene in cylinders GOST 5457−75.

Tartaric acid according to GOST 5817−77, a solution with a mass concentration of 400 g/DM.

Nitric acid GOST 4461−77, distilled in a quartz apparatus, or nitric acid according to GOST 11125−84 and diluted 1:3, 1:1 and 1:2.

Lead according to GOST 3778−77* with a mass fraction of zinc is not more than 0.0001%.
______________
* On the territory of the Russian Federation GOST 3778−98. — Note the manufacturer’s database.

A solution with a mass concentration of lead 100 g/l, prepared by dissolving 25 g of chips of metal lead 100 cmof nitric acid (1:3) under heating. The resulting solution was transferred to volumetric flask with a capacity of 250 cm, was adjusted to the mark with water and mix.

Zinc GOST 3640−79*.
______________
* On the territory of the Russian Federation GOST 3640−94. — Note the manufacturer’s database.

Copper GOST 859−78 not below the mark M0 or electrolyte.

(Changed edition, Rev. N 1, 2).

2.3. Preparation for assay

2.3.1. Preparation of standard solutions of zinc and copper

Solution a: 0,1000 g of zinc is dissolved in 15 cmof nitric acid (1:3) under heating. After cooling, the solution is transferred into a measuring flask with volume capacity of 1000 cm, made up to the mark with water and mix.

1 cmof the solution contains 100 micrograms of zinc.

Solution B: 10 cmsolution And transferred to a volumetric flask with a capacity of 100 cm, adjusted to the mark with water and mix.

1 cmof a solution containing 10 mg of zinc.

Solution: 10 cmof a solution transferred to a volumetric flask with a capacity of 100 cm, adjusted to the mark with water and mix.

1 cmof the solution contains 1 mg of zinc.

Solution G: 0,5000 g of copper is dissolved in 10 cmof nitric acid solution 1:1 under heating. After cooling, the solution is transferred to a volumetric flask with a capacity of 500 cm, made up to the mark with water and mix.

1 cmsolution G contains 1 mg of copper.

Solution D: 10 cmsolution G is transferred to a volumetric flask with a capacity of 100 cm, adjusted to the mark with water and mix.

1 cmof solution e contains 100 micrograms of copper.

Solution E: 10 cmof solution D, transferred into a measuring flask with a capacity of 100 cm, adjusted to the mark with water and mix.

1 cmof solution E contains

10 µg of copper.

2.3.2. Construction of calibration curve

In eight of the nine volumetric flasks with a capacity of 100 cmpour 10 and 20 cmstandard solution, 5, 10 and 20 cmstandard solution B, 5, 8 and 10 cmstandard solution A, which corresponds to 0,1; 0,2; 0,5; 1; 2; 5; 8 and 10 µg/cmof zinc.

To all flasks add 12 cmof a solution of nitric acid 1:2 and 20 cmof a solution of lead, adjusted to the mark with water and mix.

In nine out of ten volumetric flasks with a capacity of 100 cmeach placed 4, 8, 10, and 20 cmstandard solution E, 5, 10 and 20 cmstandard solution D, 4 and 6 cmstandard solution G, which corresponds to 0,4; 0,8; 1; 2; 5; 10; 20; 40 and 60 µg/cmof copper.

To all flasks add 12 cmof nitric acid solution 1:2, adjusted to the mark with water and traveling.

sivut.

2.3.1, 2.3.2. (Changed edition, Rev. N 2).

2.4. Analysis

A portion of the alloy weight of 2,0000 g is placed in a conical flask with a capacity of 250 cm, 5 cm pourthe tartaric acid solution and 15 cmof nitric acid (1:2) and dissolved by heating. The solution was cooled, transferred to a volumetric flask with a capacity of 100 cm, made up to the mark with water and mix.

Analyzed and standard solutions sprayed in air-acetylene flame and measure the magnitude of the absorption line of zinc 213,8 nm line of copper 324,8 nm on an atomic absorption spectrophotometer.

Measurement conditions selected in accordance with the applicable device. Use two ways to measure the magnitude of the absorption depending on the instrument model.

For spectrophotometers with work mode «concentration», «concentration» and get on the scoreboard in µg/cmor in the «absorption» method «limiting solutions», or by the calibration schedule.

On the other spectrophotometers operate in the mode «absorption» recording on a recording potentiometer or by deposition on a dial or digital device.

The method of «limiting solutions» is to obtain the counts for the analyzed solution and the two standard solutions, one of which gives a higher and the other lower count compared to the count for the analyzed solution.

(Changed edition, Rev. N 2).

2.5. Processing of the results

2.5.1. If the measurement is performed at the recording potentiometer, a ruler measure the height of the peaks in millimeters and build a calibration curve in the coordinates:  — the concentration of the element in solution, mg/cm; is the peak height, mm.

When measurement of the absorption line of the element by analog and digital instrument calibration curve constructed in the coordinates:  — the concentration of the element in the solution, µg/cm,  — the testimony of a dial or digital device.

Mass fraction of zinc and copper () in percent is calculated by the formula

,

where is the concentration of zinc or copper in the sample solution, µg/cm;

the concentration of zinc or of copper in solution in the reference experiment, µ g/cm;

the volume of the solution of the alloy, cm;

 — weight alloy, g

.

2.5.2. The discrepancy between the results of parallel measurements (the difference between the largest and smallest results of parallel measurements) and the discrepancy between the results of the analysis (the difference between the larger and the smaller of the results of the analysis) at a confidence level =0.95 does not exceed the permissible values of absolute differences are given in table.1 and 2.

Table 1

Table 2

The control accuracy of the analysis is carried out using standard samples or by other methods stipulated by GOST 1293.0−83.

The error analysis results (at a confidence probability =0,95) does not exceed the limit values given in table.1 and 2, if the following conditions are true: the discrepancy between the results of parallel measurements does not exceed the permissible, the results of accuracy control positive.

2.5.3. Method of determination of zinc used in the disagreement in assessing the quality of the alloy.

2.5.1−2.5.3. (Changed edition, Rev. N 2).

3. POLAROGRAPHIC METHOD FOR THE DETERMINATION OF ZINC AND COPPER

3.1. The essence of the method

The method is based on the polarographic determination of zinc and copper in ammonium-ammonia background electrolyte at potentials of half wavelengths of 1.44, respectively minus and minus 0,52 versus the saturated calomel electrode. Lead pre-allocate in the form of sulphate, antimony partially Coosada with lead, and another part is removed in the form of volatile bromide of antimony.

3.2. Apparatus, materials and reagents

Polarograph AC.

Nitric acid GOST 4461−77 diluted 1:1.

Sulfuric acid GOST 4204−77, diluted 1:1 and 1:50.

Hydrochloric acid by the GOST 3118−77 and diluted 1:20.

Ammonia water according to GOST 3760−79.

Ammonium chloride according to GOST 3773−72.

Bromatologia acid according to GOST 2062−77.

Iron chloride according to GOST 4147−74, a solution of 50 g/DM: prepare to dilute 1:20 hydrochloric acid.

Sanitarily sodium (sodium sulfite) the crystal according to GOST 195−77, saturated solution.

Zinc GOST 3640−79*.
______________
* On the territory of the Russian Federation GOST 3640−94. — Note the manufacturer’s database.

Copper GOST 859−78, mark M0.

(Changed edition, Rev. N 1, 2).

3.3. Preparation for assay

3.3.1. Preparation of standard solutions of zinc and copper

Solution a: of 0.2000 g of zinc and of 0.2000 g of copper is dissolved in 15−20 cmof nitric acid (1:1) and evaporated to obtain a wet residue. Pour 10 cmof hydrochloric acid and again evaporated to obtain a wet residue.

Evaporation with hydrochloric acid is repeated twice. Add 50 cmof hydrochloric acid, transferred into a volumetric flask with a capacity of 1 DM, adjusted to the mark with water and mix.

1 cmof the solution contains 0.2 mg of zinc, and copper.

Solution B: 10 cmstandard solution And dilute hydrochloric acid, diluted 1:20 in a volumetric flask with a capacity of 100 cm.

1 cmof the solution contains 0.02 mg of zinc and copper.

3.3.2. To prepare the calibration solutions in seven volumetric flasks with a capacity of 100 cmmeasured 2 cmof a solution, 0,5; 1; 2; 5; 10 and 15 cmof the solution And poured into each of the flasks, except the last, hydrochloric acid, diluted 1:20 volume of 15 cm, 40−50 cm,background electrolyte and 4 cmof a solution of ferric chloride, mix, pour 10 cmof a saturated solution of sodium sulfite, dilute to the mark and the background electrolyte and stirred.

The calibration solutions contain respectively 0,4; 1,0; 2,0; 4,0; 10,0; 20,0 and 30.0 mg/DMof zinc and copper.

The number and concentration of calibration solutions of zinc and copper vary depending on the concentration of these elements in the analyzed solution

E.

3.3.1, 3.3.2. (Changed edition, Rev. N 2).

3.3.3. For preparation of background electrolyte in a flask with a capacity of 1 DMpour 500 cmof water, add 100 g ammonium chloride, 200 cmof ammonia, mix to dissolve the salt and dilute with stirring to the mark with water.

3.4. Analysis

A portion of the alloy weight of 5,0000 or 10,000 g is placed in a conical flask with a capacity of 250 cm, 60−80 cm pourednitric acid (1:1) and heated until complete dissolution of the alloy. Pour 50 cmof water, 10 cmof sulphuric acid diluted 1:1, heated to boiling, cooled for 30 min and filtered through a dense filter of «blue ribbon», collecting the filtrate in a volumetric flask with a capacity of 250 cm. The precipitate on the filter and in the flask is washed 3−4 times with cold sulphuric acid, diluted 11:50. Filter the precipitate of lead sulphate is discarded.

To the filtrate in the volumetric flask, add 5 cmof sulphuric acid (1:1) was adjusted to the mark with water and mix.

Aliquot part of the solution was 25 or 50 cm, depending on the mass fraction of zinc and copper, placed in a conical flask with a capacity of 100 cm, poured 5cmof hydrochloric acid and evaporated until the appearance of dense sulphuric acid fumes. Cooled and evaporation with 5 cmof hydrochloric acid is repeated. Pour 5 cmbromatological acid and evaporated until the appearance of sulphuric acid fumes. Evaporation from bromatological acid repeated twice or thrice, depending on the content of antimony in the alloy. Wash the walls of the bulb 1−2 cmof water and evaporated until complete removal of sulphuric acid fumes.

To slightly wet the residue is poured depending on the final dilution of 4 or 8 cmof a hydrochloric acid solution, heated to 50−60 °C, pour 10 or 25 cm,background electrolyte 1 or 2 cmof a solution of ferric chloride, stirred, poured 2.5 or 5 cmof a saturated solution of sodium sulfite, cooled, quantitatively transferred to a volumetric flask with a capacity of 25 or 50 cm, dilute to the mark and the background electrolyte and stirred.

Part of the solution is poured into the cell and polarographic zinc and copper respectively at the potentials of the half-wave minus and minus 0,52 1,44 versus the saturated calomel electrode.

In similar conditions hold polarographically zinc and copper in the calibration solutions and in the solution in the reference experiment by subtracting the values of the wave heights of zinc and copper in the reference experiment from the corresponding values of the analyzed alloy.

(Changed edition, Rev. N 1, 2).

3.5. Processing of the results

3.5.1. Mass fraction of zinc (and copper) () percentage calculated by the formula

,

where  — height of a wave of zinc (copper) solution of the alloy, mm;

the volume of the solution of the alloy, cm;

 — the weight of the portion of the alloy (the weight of the portion corresponding to aliquote part of the solution), g;

the conversion factor is calculated by the formula

,

where  — height of a wave of zinc (copper) of the calibration solution;

the concentration of zinc (copper) in calibration solution, mg/DM.

3.5.2. The discrepancy between the results of parallel measurements (the difference between the largest and smallest results of parallel measurements) and the discrepancy between the results of the analysis (the difference between the larger and the smaller of the results of the analysis) at a confidence level =0.95 does not exceed the permissible values of absolute differences are given in table.1 and 3.

Table 3

The control accuracy of the analysis is carried out using standard samples or by other methods stipulated by GOST 1293.0−83.

The error analysis results (at a confidence probability =0,95) does not exceed the limit values given in table.1 and 3, the following conditions are true: the discrepancy between the results of parallel measurements does not exceed the permissible, the results of accuracy control positive.

3.5.1, 3.5.2. (Changed edition, Rev. N 2).