GOST 16274.2-77
GOST 16274.2−77 Bismuth. Method of determination of antimony (with Amendments No. 1, 2, 3)
GOST 16274.2−77
Group B59
STATE STANDARD OF THE USSR
BISMUTH
Method for determination of antimony
Bismuth.
Method for determination of antimony content
AXTU 1709
Date of introduction 1978−01−01
INFORMATION DATA
1. DEVELOPED AND INTRODUCED by the Ministry of nonferrous metallurgy of the USSR
DEVELOPERS
PS Poklonsky, F. M. Manji, G. V. Khabarova
2. APPROVED AND promulgated by the DECREE of the State Committee of standards of Ministerial Council of the USSR from
3. The frequency of inspection 5 years
4. REPLACE GOST 16274.2−70
5. REFERENCE NORMATIVE AND TECHNICAL DOCUMENTS
| The designation of the reference document referenced |
The partition number |
| GOST 1089−82 |
Sec. 2 |
| GOST 1770−74 |
Sec. 2 |
| GOST 3118−77 |
Sec. 2 |
| GOST 4197−74 |
Sec. 2 |
| GOST 4204−77 |
Sec. 2 |
| GOST 4461−77 |
Sec. 2 |
| GOST 5789−78 |
Sec. 2 |
| GOST 6691−77 |
Sec. 2 |
| GOST 7851−74 |
Sec. 2 |
| GOST 10928−90 |
Sec. 2 |
| GOST 16274.0−77 |
Sec. 1 |
| THAT 6−09−5393−88 |
Sec. 2 |
6. Resolution of the state standard from
7. REPRINT (July 1997) with Amendments No. 1, 2, 3, approved in January 1983, June 1987, July 1992 (IUS 5−83, 11−87, 10−92)
This standard applies to bismuth brands Vi1 and Vi2 and sets photocolorimetric method for determination of antimony (when the content of antimony from 0.003 to 0.02%).
The method is based on extraction with toluene colored complex compounds of antimony with crystal violet and measuring the optical density of the extract.
(Changed edition, Rev. N 1).
1. GENERAL REQUIREMENTS
General requirements for method of analysis according to GOST 16274.0.
2. APPARATUS, REAGENTS AND SOLUTIONS
Photoelectrocolorimeter.
Volumetric flasks with a capacity of 1000, 200, 100 cmaccording to GOST 1770.
Pipettes with a capacity of 5, 10, 20 cmfor NTD.
Microburette with a capacity of 5 cmin the NTD.
Conical flasks with a capacity of 250 cmaccording to GOST 7851.
The chemical glasses with a capacity of 50 cmaccording to GOST 7851.
Separating funnel with a capacity of 100 cm.
Sulfuric acid according to GOST 4204, and a 10% solution.
Hydrochloric acid according to GOST 3118, diluted 1:1 and 3:1.
Tin dichloride on the other 6−09−5393, 5% solution in hydrochloric acid diluted 1:1.
Sodium atomistically according to GOST 4197, 20% solution.
Urea according to GOST 6691, a saturated solution is prepared as follows: 50 g of urea are dissolved in 50 cmof hot water.
Purple crystal, a 0.1% solution.
Toluene according to GOST 5789.
Antimony brand Su00 according to GOST 1089.
Standard solutions of antimony.
Solution 1; prepared as follows: 0.1 g of antimony is dissolved by heating in 20 cmof concentrated sulfuric acid. After cooling, add 200−300 cm
of water and 80 cm
of concentrated sulfuric acid. 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 0.1 mg of antimony.
Solution 2; prepared as follows: 10 cmof solution 1 is placed in a volumetric flask with a capacity of 200 cm
, made up to the mark of 10% sulfuric acid solution and stirred.
1 cm2 working solution contains 0.005 mg of antimony, prepared on the day of use.
The brand Vi00 bismuth GOST 10928.
The solution of salt of bismuth is prepared as follows: in a conical flask with a capacity of 250 cmis placed 1 g of metallic bismuth grade not lower Vi00, add 5 cm
of nitric acid, diluted 1:1 was dissolved, the solution was evaporated to dryness, cooled, to the residue poured 3 cm
of sulphuric acid and evaporate to release thick vapors of sulfuric acid. After cooling, the flask wall is washed with water and poured 50 cm
hydrochloric acid, diluted 3:1. The resulting solution was transferred to volumetric flask with a capacity of 100 cm
, made up to the mark with hydrochloric acid, diluted 3:1, and stirred.
Nitric acid according to GOST 4461, diluted 1:1.
(Changed edition, Rev. N 2, 3).
3. ANALYSIS
3.1. Weighed 1 g of bismuth placed in a conical flask with a capacity of 250 cm, 5 cm pour
nitric acid, diluted 1:1, and dissolved. The solution was evaporated to dryness, cooled, and then the remainder poured 3 cm
of sulphuric acid and evaporate to release thick vapors of sulfuric acid. After cooling, wash the walls of the bulb with water and poured 50 cm
hydrochloric acid, diluted 3:1. The resulting solution was transferred to volumetric flask with a capacity of 100 cm
and adjusted to the mark with hydrochloric acid, diluted 3:1.
In a glass with a capacity of 50 cm, measure out 5 cm
of the solution, add one drop of a solution of tin dichloride, stirred, is added 1 cm
of a solution of sodium nitrite and allowed to stand for 5 min, then add 1.5 cm
of the urea solution, allow to stand out the bulk of the gas, transfer the solution in a separating funnel with a capacity of 100 cm
and rinse the Cup with water. The solution in the funnel topped up with water to 50 cm
.
The solution is poured 0.5 cmpurple crystal, stirred and extracted antimony 20 cm
of toluene for 1 min.
The optical density of the toluene solution is measured on photoelectrocolorimeter at a wavelength of 610 nm in a cuvette with the thickness of the light absorbing layer 30 mm.
A solution of comparison used toluene.
The content of antimony found by the calibration schedule.
(Changed edition, Rev. N
2, 3).
3.2. Construction of calibration curve.
In glasses with a capacity of 50 cm, measure off microburette 0,5; 1; 1,5; 2 and 3 cm
working solution 2, which corresponds to RUB 0.0025; to 0.005; 0,0075; 0.01 and 0.015 mg of antimony, and heated to stop the allocation of the vapour of sulphuric anhydride. To the dry residue poured 5 cm
of a solution of salt of bismuth, one drop of a solution of tin dichloride and further analysis are as indicated in claim 3.1.
On the found values of optical densities and corresponding concentrations of antimony in building the calibration curve.
(Changed edition, Rev. N 2).
4. PROCESSING OF THE RESULTS
4.1. The contents of antimony () in percent is calculated by the formula
where the amount of antimony found in the calibration graphics mg;
— the total volume of solution, cm
;
— aliquota part of the solution was taken to determine cm
;
— hitch, g;
1000 — conversion factor for grams to milligrams.
4.2. The maximum discrepancy between the results of three parallel measurements () and the results of two tests (
) at a confidence probability of 0.95, should not exceed the values given in the table.
| Mass fraction of SB, % |
The discrepancy between the results of three parallel definitions % |
The discrepancy between the results of two tests, % |
| 0,0030 |
0,0012 | 0,0015 |
| 0,005 |
0,002 | 0,003 |
| 0,010 |
0,004 | 0,005 |
| 0,020 |
0,008 | 0,010 |
Permitted discrepancies for the intermediate mass fraction calculated using linear interpolation or according to the formulas:
where is the arithmetic mean of results of three parallel measurements;
— the arithmetic mean of the results of the two tests.
(Changed edition, Rev. N 3).
