GOST 1367.3-83

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  ГОСТ 1367.3-83

Group B59

INTERSTATE STANDARD

ANTIMONY Method of determining gilding

GOST 1367.3−83 Instead of GOST 1367.3−76

Antimony. Method for the determination of aurum

AXTU 1709

1 (stopped State Committee of USSR on standards or on 16 December 1983, No. 6012 date of introduction is established 01.01.8 S

The expiration time limit removed on the Ns Protocol 4−93 inter-state Council on standarten. Metrology and certification (ICS 4−94)

This standard establishes the atomic absorption method for the determination of gold from 1 • 10 ⁶ to 2 I0-³ % antimony grades Su0000, Soooooo, Sooooo, Soooo, Soooo, MSA and SS2.

The method is based on measuring atomic absorption of gold with the introduction of the sample solution and solutions compare to the flames of propane-butane-air or acetylene-air.

(Changed edition, Rev. No. 1).

1. GENERAL REQUIREMENTS

1.1. General requirements for methods of analysis and security requirements — according to GOST 1367.0−83.

2. APPARATUS, REAGENTS AND SOLUTIONS

Spectrophotometer atomic absorbion Perkin-Elmer 503 or equivalent atomic absorption spectrophotometer.

Gas propane-butane according to GOST 20448−90.

Mechanical peremahival type AG1−1.

Glasses or Kaaba, glass, laboratory for GOST 25336−82 capacity of 100. 250 cm³.

Volumetric flasks according to GOST 1770−74 capacity of UW. 250 cm³.

Pipette with divisions for NTD with a capacity of I, 2, 5, 10 cm⁵.

For nitric acid GOST 4461−77.

Hydrochloric acid by the GOST 3118−77, 3 mol/DM^; the solution of the first days&Tenna 1:1.

Toluene according to GOST 5789−78.

Tartaric acid according to GOST 5817−77.

The sulfoxide. debugenabled 0.2 mol/DM³ solution in toluene.

Gold metal according to GOST 6835−2002.

Standard solutions of gold.

Solution a: 0.1 g of gold was placed in a beaker with a capacity of 100 cm⁵, 30 cm pour⁵ Aqua Regia (a mixture of acids consisting of nitric and hydrochloric acids (1:3) and heated until complete dissolution of gold. Then the gold solution was cooled, transferred to a volumetric flask with a capacity of 100 cm³, bring to the mark with hydrochloric acid (1:1) and stirred. The solution was stored in a dark place.

I see' solution, And contains 1 mg of gold.

Solution B: 1 cm' of a solution, And transferred to a volumetric flask with a capacity of 100 cm\ of the label is adjusted to 3 mol/DM³ hydrochloric acid solution and stirred, prepared on the day of application.

Edition official Reprint weerasena

Edition Change. M> /, approved in March 1989 (IUS 6−89).

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GOST 1367.3−83 C. 2

I cm' of a solution containing 10 micrograms of gold.

(Changed edition, Rev. No. 1).

3. ANALYSIS

3.1. A portion of the antimony with a mass of I g (for antimony grades Soooooo. Swoooop, Sooooo — 5 g) was placed in a beaker or conical flask with a capacity of 100−250 cm³, flow 40 cm^! a mixture of concentrated hydrochloric acid and asopus (3:1) and heated to dissolve sample. The contents of the beaker evaporated to wet salts, add 40 cm' 3 mol/DM³ hydrochloric acid solution, 5 g of tartaric acid and heated to dissolve the salts. After cooling, the solution is transferred to a volumetric flask with a capacity of 250 cm³, pour the 3 mol/DM³ hydrochloric acid solution to a volume of 100−120 cm³, 5 cm³ of a solution of the sulfoxide in toluene and extracted the gold with the aid of mechanical peremen-wash system for 30 min. in the absence of laboratory mechanical agitator the extraction is carried out manually stirring the solution for 5 minutes, Then poured into a flask of 3 mol/DM³ hydrochloric acid solution to move the organic layer in the narrow part of the flask and closed with a plug (cotton swab the crucible, etc.).

3.2. Working conditions in the spectrophotometers of different types choose according to the instructions for their use.

The measurement of the absorption line of gold is carried out when spraying of the extract in the flame is starved of fuel gas. Prior measurements of the absorption set zero on the instrument, spraying into the flames of toluene. The extract is sprayed into the flame and measure the absorbance at the wavelength 242,8 nm.

A lot of gold in the extract is determined according to the calibration schedule. If the amount of absorption of the analyzed extract exceeds the maximum value of the absorption calibration curve. the extract is diluted with toluene.

(Changed edition, Rev. No. 1).

4. CONSTRUCTION OF CALIBRATION CURVE

In a volumetric flask with a capacity of 100 cm^{3 is} poured successively 0,25; 0.5; 1,0; 1,5; 2,0 cm⁵ standard solution B, 20−25 cm³ 3 mol/DM³ hydrochloric acid solution, 10 cm³ of a solution of the sulfoxide in toluene and extracted gold for 15 min on a mechanical mixer or 3 min with manual stirring. The concentration of gold in the obtained extracts respectively equal to 0,25; 0,5; 1,0; 1,5; 2,0 mg/cm³. Then pour the flask of water to move the organic layer in their narrow and closed with a plug (cotton swab, crucible, etc.).

The obtained extracts are sprayed into the flame in order of increasing content of gold.

Measurement of analytical signal, And for each of the obtained extracts and the comparison of extracts from samples carried out three times and calculate the average arithmetic values of I = j (A_t + L₂ + L_}) for each extract. On the average, And extracts

comparisons build the calibration graph. The abscissa shows the lay concentration of gold, and on the y — axis the absorbance.

(Changed edition, Rev. No. 1).

5. PROCESSING OF THE RESULTS

5.1. Mass fraction of gold (AO in percent is calculated by the formula

t

where C is the concentration of gold in the extract of the sample, was found for the calibration graph and the average value obtained for A. extract samples, µg/cm³;

To-the volume of extract of the sample, cm'; t — the weight of antimony,

33

C. 3 GOST 1367.3−83

5.2. The difference between the two results of parallel measurements and the difference of two analysis results with a confidence probability P = 0.95 does not exceed the allowable absolute differences of precision and reproducibility, are given in the table.

Mass fraction of Yul otd. % Valcanoe permitted discrepancy. % convergence howling and ROI 1воа and m osti From 10−10"7 to 20−10 7 in the key. 7−10' 7 8 10−7 SV. 20 10″ * 50−10"7 * 15-M"7 17−10−7 * 50−10"7. 10-I0−4 «Zoe-7 10−7 40 «I0-UT6 * 20−10"6 * 50 10−7 60 10−7 20-ИГ6 * 50 10"6 * 10 10» 6 12−10−6 * 50 10−6 «10 10−5. 20 10-* 2510-ü «10−10» d * 20−10"5 * 5−10- 5 IO~5 * 2010"S * 5010'1 * 10 10"5 12−10−5 * 50−10"5 * 1010- 4. 20 I0−1 25−10−5 «YU"4 * 20 10"4 * 5 10−4 6 10~4

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