GOST 15027.13-77
GOST 15027.13−77 Bronze without tin. Methods for determination of beryllium (with Amendments No. 1, 2, 3)
GOST 15027.13−77
Group B59
INTERSTATE STANDARD
BRONZE WITHOUT TIN
Methods for determination of beryllium
Non-tin bronze.
Methods for the determination of berylium
AXTU 1709
Date of introduction 1979−01−01
INFORMATION DATA
1. DEVELOPED AND INTRODUCED by the Ministry of nonferrous metallurgy of the USSR
2. APPROVED AND promulgated by the Decree of the State Committee of standards of Ministerial Council of the USSR from
3. REPLACE GOST 15027.13−69
4. The standard fully complies ST SEV 1536−79
5. REFERENCE NORMATIVE AND TECHNICAL DOCUMENTS
The designation of the reference document referenced | Section number, paragraph, sub-paragraph |
GOST 61−75 |
2 |
GOST 3117−78 |
2 |
GOST 3118−77 |
2 |
GOST 3760−79 |
2 |
GOST 3765−78 |
2 |
GOST 3772−74 |
2 |
GOST 4204−77 |
2 |
GOST 4461−77 |
2; 5 |
GOST 6563−75 |
2 |
GOST 10652−73 |
2 |
GOST 10929−76 |
2 |
GOST 18175−78 |
Chapeau |
GOST 18300−87 |
2 |
GOST 22867−77 |
2 |
GOST 25086−87 |
1.1; 4.4; 5 |
6. Limitation of actions taken by Protocol No. 3−93 Interstate Council for standardization, Metrology and certification (ICS 5−6-93)
7. EDITION with Amendments No. 1, 2* approved in February 1983, March 1988 (IUS 6−83, 6−88)
___________________
* Probably, the error of the original. Should read «with Amendments No. 1, 2, 3». Change No. 3, published in IUS 3−91 and included in the text of the standard. — Note the manufacturer’s database.
This standard specifies the gravimetric and atomic absorption methods for the determination of beryllium (with a mass fraction of beryllium from 1.5% to 2.5%) in the tin bronze according to GOST 18175.
(Changed edition, Rev. N 1, 2, 3).
1. GENERAL REQUIREMENTS
1.1. General requirements for methods of analysis GOST 25086 with the addition of sec. 1 GOST 15027.1.
(Changed edition, Rev. N 1, 2).
1A. GRAVIMETRIC METHOD FOR THE DETERMINATION OF BERYLLIUM
The essence of the method
The method is based on the deposition of beryllium in the form of phosphate, the calcination and weighing the calcined residue. Before the deposition of beryllium copper is separated by electrolysis or copper in the form of ammonia complex remains in the filtrate. Aluminum and iron mask by adding a solution of Trilon B. In the presence of a titanium mask it with hydrogen peroxide.
(Added, Rev. N 3).
2. APPARATUS, REAGENTS AND SOLUTIONS
Installation of electrolysis with a platinum mesh electrode according to GOST 6563.
a pH meter.
Nitric acid according to GOST 4461, diluted 1:1.
Sulfuric acid according to GOST 4204, diluted 1:4.
Ammonia water according to GOST 3760.
Ammonium disodium phosphate according to GOST 3772 solution of 100 g/DM.
Hydrochloric acid according to GOST 3118, diluted 1:1.
Methyl red (indicator), ethanolic solution of 2 g/DM.
Salt is the disodium Ethylenediamine-N, N, N', N'-tetraoxane acid 2-water (Trilon B) according to GOST 10652, solution; is prepared as follows: 15 g of Trilon B is mixed with a small amount of water and poured ammonia to dissolve the sample Trilon B. the Solution is diluted with water up to 70−80 cm, filtered and the filtrate neutralized with hydrochloric acid diluted 1:1, until the pink colour in methyl red, then add ammonia to the yellow colouring and add water to 100 cm.
Ammonium acetate according to GOST 3117, a solution of 150 g/DM.
Ammonium nitrate according to GOST 22867, a solution of 10 g/DM.
Hydrogen peroxide according to GOST 10929.
Ammonium molybdate according to GOST 3765, a freshly prepared solution of 100 g/DM.
Acetic acid according to GOST 61.
Irrigation solution (pH of 5.2); prepared as follows: 15 cmof a solution of ammonium acetate is diluted with water to a volume of 1000 cmand adding acetic acid, the pH of the solution was adjusted to 5.2±0,05.
Rectified ethyl alcohol according to GOST 18300.
Irrigation solution: a solution of ammonium nitrate neutralized with ammonia solution on methyl red.
(Izmena edition, Rev. N 2, 3).
3. ANALYSIS
3.1. The weight of bronze weighing 0.5 g were placed in a glass with a capacity of 250 cmand dissolved by heating in 15 cmof nitric acid, diluted 1:1. The solution was boiled to remove oxides of nitrogen, cool, add 7 cmof sulphuric acid, diluted 1:4, 100 cmof water and produce copper by electrolysis according to GOST 15027.1
At the end of the electrolysis, the solution was boiled down to 100 cm, add 3 cmof the solution Trilon B (for analysis of bronzes, containing titanium, 5 cmof hydrogen peroxide) and set the pH of the solution 1.5 ammonia by indicator paper or pH-meter.
The solution is heated to boiling and boiled for 3 min. Then solution was cooled, added to 10 cmof a solution of ammonium phosphate, adjusted pH to 5.2 with a solution of acetate of ammonia, heated to boiling and boiled for 3−5 min. the Solution was cooled and, after 1 h, the precipitate is filtered off on a medium density filter, washing the filter residue with 5−8 times the irrigation solution (pH 5,2) to a negative reaction for phosphate ions (sample with ammonium molybdate solution).
The washed precipitate is transferred with the filter in a weighed porcelain crucible, dried, incinerated and calcined at 800−900 °C for 1 h to constant weight, cooled and weighed.
(Izmena edition, Rev. N 1, 3
).
3.2. The weight of bronze weighing 0.5 g were placed in a glass with a capacity of 250 cmand dissolved by heating in 15 cmof nitric acid, diluted 1:1. The solution was boiled to remove oxides of nitrogen, and cooled.
The walls of the beaker rinse with water, add 40−50 cmof the solution Trilon B, 15 cmof ammonium phosphate solution (100 g/DM) and ammonia solution dropwise until the appearance of stable turbidity. Then poured to a solution of 25 cmof a solution of ammonium acetate and heated to boiling. Solution and the precipitate is kept in a warm place or in a water bath to precipitate the transition from amorphous state to crystalline.
After cooling, the precipitate was filtered off on a thick filter or a double with a white stripe and rinsed with irrigation solution until complete removal of copper ions and a negative reaction for phosphate ions (sample with ammonium molybdate solution) and further receives, as described in Chapter 3.1.
(Added, Rev. N 2).
4. PROCESSING OF THE RESULTS
4.1. Mass fraction of beryllium (a) percentage calculated by the formula
,
where is the mass of phosphate precipitate of beryllium, g;
0,0938 — ratio phosphate of beryllium on beryllium;
— weight of bronze,
4.2. The absolute discrepancies in the results of parallel measurements (the rate of convergence) must not exceed 0.05%.
(Changed edition, Rev. N 2).
4.3. The absolute discrepancies of the analysis results obtained in two different laboratories or two of the results of analysis obtained in the same laboratory but under different conditions (a measure of reproducibility) shall not exceed 0,07.
4.4. Control of accuracy of analysis results
Control of accuracy of analysis results is carried out according to State standard samples without tin bronzes, certified in the prescribed manner, or by comparison of the results obtained by atomic absorption method in accordance with GOST 25086.
4.3, 4.4. (Changed edition, Rev. N 2, 3).
5. ATOMIC ABSORPTION METHOD FOR THE DETERMINATION OF BERYLLIUM
5.1. The essence of the method
The method is based on measuring the absorption of light by atoms of beryllium formed during the introduction of the analyzed solution in the flame acetylene-nitrous oxide at a wavelength 234,9 nm.
5.2. Apparatus, reagents and solutions
Atomic absorption spectrometer with a source of radiation to beryllium.
Nitric acid according to GOST 4461, diluted 1:1.
Beryllium sulfate (BeSO·4N).
Standard solutions of beryllium.
Solution a: 19,65 g of beryllium sulphate is dissolved in water, transferred to a measuring flask with volume capacity of 1000 cmand top up with water to the mark.
1 cmof the solution contains 0.001 g of beryllium.
Solution B: 10 cmsolution And transferred to a volumetric flask with a capacity of 100 cmand top up with water to the mark.
1 cmof a solution contains 0.0001 g of beryllium
.
5.3. Analysis
5.3.1. A portion of sample weighing 0.1 g was dissolved with heating in 10 cmof nitric acid (1:1). The solution was transferred to a volumetric flask with a capacity of 100 cmand top up with water to the mark. Aliquot part of the solution was 10 cm,transferred to a volumetric flask with a capacity of 100 cmand top up with water to the mark.
Measure the atomic absorption of beryllium in the flame acetylene-nitrous oxide at a wavelength 234,9 nm parallel to the calibration solutions.
5.3.2. Construction of calibration curve
Five volumetric flasks with a capacity of 100 cmis placed 0,5; 1,0; 2,0; 3,0 and 4,0 cmstandard solution B, which corresponds to 0,05; 0,1; 0,2; 0,3 and 0,4 mg of beryllium and topped to the mark with water. Measure the atomic absorption beryllium, as specified in clause 5.3.1, according to the obtained results build a calibration curve.
5.4. Processing of the results
5.4.1. Mass fraction of beryllium (a) percentage calculated by the formula
,
where is the concentration of beryllium in the analyzed solution samples, was found in the calibration schedule, g/cm;
— the dilution factor;
— the volume of the sample solution, cm;
— the weight of the portion of the sample,
5.4.2. The absolute discrepancies in the results of parallel measurements (the rate of convergence) must not exceed 0.05%.
5.4.3. The absolute discrepancies of the analysis results obtained in two different laboratories or two of the results of analysis obtained in the same laboratory but under different conditions (a measure of reproducibility) shall not exceed 0.07 percent.
5.4.4. Control of accuracy of analysis results
Control of accuracy of analysis results is carried out according to State standard samples without tin bronzes, certified in the prescribed manner, or by comparison of the results obtained by the gravimetric method, in accordance with GOST 25086.
Sec. 5. (Added, Rev. N 3).