GOST 1953.1-79
GOST 1953.1−79 Bronze tin. Methods for determination of copper (with Amendments No. 1, 2)
GOST 1953.1−79
Group B59
INTERSTATE STANDARD
BRONZE TIN
Methods for determination of copper
Tin bronze.
Methods for the determination of copper
AXTU 1709
Date of introduction 1981−01−01
INFORMATION DATA
1. DEVELOPED AND INTRODUCED by the Ministry of nonferrous metallurgy of the USSR
2. APPROVED AND put INTO EFFECT by Decision of the USSR State Committee for standards from
3. The standard fully complies ST SEV 1527−79
4. REPLACE GOST 1953.1−74
5. REFERENCE NORMATIVE AND TECHNICAL DOCUMENTS
| The designation of the reference document, to which this links |
Section number, paragraph, sub-paragraph |
| GOST 8.315−97 |
4.5 |
| GOST 613−79 |
Chapeau |
| GOST 614−97 |
Chapeau |
| GOST 859−2001 |
2.2 |
| GOST 1953.2−79 |
2.3 |
| GOST 1953.3−79 |
2.3 |
| GOST 1953.5−79 |
2.4.2 |
| GOST 2062−77 |
3.2 |
| GOST 3760−79 |
3.2 |
| GOST 3652−69 |
2.1 |
| GOST 4109−79 |
3.2 |
| GOST 4204−77 |
2.2, 3.2 |
| GOST 4207−75 |
2.2 |
| GOST 4461−77 |
2.2, 3.2 |
| GOST 5017−74 |
Chapeau |
| GOST 5457−75 |
2.2 |
| GOST 5841−74 |
3.2 |
| GOST 6563−75 |
2.2, 3.2 |
| GOST 6691−77 |
3.2 |
| GOST 9656−75 |
3.2 |
| GOST 10484−78 |
3.2 |
| GOST 18300−87 |
2.2, 3.2 |
| GOST 22867−77 |
2.2 |
| GOST 25086−87 |
1.1, 4.4 |
6. Limitation of actions taken by Protocol No. 5−94 of the Interstate Council for standardization, Metrology and certification (ICS 11−12−94)
7. EDITION with Amendments No. 1 and No. 2, approved in February 1983, August 1990 (IUS 6−83, 11−90)
This standard specifies gravimetric methods for the electrolytic determination of copper in tin bronze according to GOST 5017, GOST GOST 614 and 613.
The standard fully complies ST SEV 1527−79.
(Changed edition, Rev. N 1, 2).
1. GENERAL REQUIREMENTS
1.1. General requirements for methods of analysis GOST 25086 add: the results of the analysis taking the arithmetic mean of results of three (two) of parallel definitions.
(Changed edition, Rev. N 1, 2).
2. GRAVIMETRIC, ELECTROLYTIC METHOD OF DETERMINING COPPER WITH A PRELIMINARY SEPARATION OF TIN AND LEAD
2.1. The essence of the method
The method is based on the allocation of copper by electrolysis after prior separation of tin in the form of metalbands acid and lead in sulfuric acid and weighing the evolved at the cathode precipitate of copper and the subsequent determination of residual copper in the electrolyte by atomic absorption spectrometry or photometric method with the use of cuprizone.
(Changed edition, Rev. N 1).
2.2. Apparatus, reagents and solutions
Installation of electrolysis.
The electrodes are platinum according to GOST 6563.
Spectrometer of atomic absorption.
Lamp with a hollow copper cathode.
Drying Cabinet.
Photoelectrocolorimeter or spectrophotometer.
Citric acid according to GOST 3652.
Ammonium citrate solution, prepared as follows: 150 g of citric acid dissolved in 400 cmof water, add with stirring 100 cm
of concentrated ammonia solution, cool, add another 100 cm
of ammonia, cool and add water to 1000 cm
.
Bis-cyclohexanone-oxalyl-dihydrazone (cuprizone), the solution is prepared as follows: 2.5 g cuprizone dissolved with stirring in 900 cmof water at a temperature of 60−70 °C.
After cooling, the solution was filtered into a dark glass jar, add water to volume of 1000 cm. The solution to fit 10 days.
Nitric acid according to GOST 4461, diluted 1:1 and 1:100.
Sulfuric acid according to GOST 4204, diluted 1:1, 1:4 and 1:100.
Potassium ferrocyanide according to GOST 4207, a solution of 300 g/DM.
Ammonium nitrate according to GOST 22867, a solution of 300 g/DM.
Copper according to GOST 859, mark M0.
A standard solution of copper, prepared as follows: 0.1 g of copper was dissolved with heating in 10 cmof nitric acid, diluted 1:1. The solution was cooled, transferred to a volumetric flask with a capacity of 1 DM
, made up to the mark with water and mix.
1 cmof the solution contains 0.0001 g of copper.
The technical rectified ethyl alcohol according to GOST 18300.
Acetylene according to GOST
5457.
2.3. Analysis
A sample weighing 1 g is placed in a beaker with a capacity of 300 cm, add 15 cm
of nitric acid, diluted 1:1, cover with a watch glass and dissolved under heating. After dissolution of the alloy watch glass is removed, rinsed with water, and the solution is evaporated to 5−10 cm
. To the residue add 50 cm
of hot water, 10 cm
of ammonium nitrate solution and allowed to stand in a warm place for 1 hour
Metalbands acid precipitate is filtered off on a tight filter with filtrowanie mass, collecting the filtrate in a beaker with a capacity of 250 cm. The filtrate and the precipitate is washed with hot nitric acid, diluted 1:100 prior to complete removal of copper (test with potassium ferrocyanide).
Selected sediment metalbands acid used in the gravimetric method for determination of tin GOST 1953.3.
The filtrate is evaporated to 150 cm, add 7 cm
of sulphuric acid, diluted 1:4. Into the solution is dipped a platinum electrode (cathode a pre-weighed) and carry out electrolysis at a current of 1.5−2 and stirring the solution. The glass electrolyte must be covered by the two halves of the hour glass or organic glass with holes for the electrodes. In the analysis of bronze containing lead from 1% to 4%, add 7 cm
of sulphuric acid (1:4) 30 minutes after the start of the electrolysis. The separated precipitate of lead dioxide on the anode used in the gravimetric method for determination of lead GOST 1953.2.
After the bleaching solution the walls of the glass, coating the glass and the protruding electrodes are then rinsed with water (15−20 cm), and continue the electrolysis for another 10−15 min at a current of 0,5 A.
If svezhemorozhenoj portion of the cathode is not allocated sediment, the electrolysis is complete. Otherwise, the electrolysis is continued for 10−15 min and re-control of the completeness of separation of copper.
At the end of the electrolysis without turning off the current, remove the electrodes from the electrolyte, rinse the electrodes and the cover glass with water, collecting the washings in the beaker with the electrolyte. Then, the cathode is immersed in a beaker with ethyl alcohol and dried at 105 °C to constant weight. One serving of alcohol (200 cm) can be used for washing no more than 20 electrodes.
In the analysis of tin-bronzes Sventevith in the filtrate after separation of the tin add 10 cmsulphuric acid diluted 1:1, and is evaporated prior to the allocation of white smoke of sulfuric acid. To the residue after cooling, add 50 cm
of water. Heated to dissolve the salts, cooled and kept for 2 h. the residue Highlighted is sulphate of lead is filtered off on a tight filter and washed 3−4 times with sulfuric acid, diluted 1:100. The residue is discarded or used as a titrimetric method for determination of lead GOST 1953.2.
To the filtrate add 10 cmboiled nitric acid, diluted 1:1, add water up to 150 cm
and carry out electrolysis, as the decree
ANO above.
2.2, 2.3. (Changed edition, Rev. N 1, 2).
2.4. Determination of residual copper in the electrolyte
The electrolyte, after separation of copper is evaporated to a volume of 40 cm, transferred to a volumetric flask with a capacity of 50 cm
, made up to the mark with water and mix.
2.4.1. Determination of residual copper by atomic absorption spectrometry
2.4.1.1. Measure the atomic absorption of copper in the flame acetylene-air at a wavelength of 324,7 nm in parallel with the solutions to construct the calibration curve.
2.4.1.2. Construction of calibration curve
In six of the seven volumetric flasks with a capacity of 100 cmis placed 0,5; 1,0; 2,0; 3,0; 4,0 and 5,0 cm
of a standard solution of copper. To all flasks add 5 cm
of nitric, diluted 1:1, and sulfuric diluted 1:1, acid, made up to the mark with water and measure the atomic absorption of copper, as indicated in claim
2.4.2. Determination of residual copper by the photometric method with cuprizone
2.4.2.1. Aliquot part of the solution — 50 cmis placed in a volumetric flask with a capacity of 100 cm
, add 10 cm
of a solution of ammonium citrate and ammonia solution, diluted 1:4, before the formation of slightly alkaline reaction, then add 2 cm
of ammonia solution diluted 1:4, 10 cm
solution cuprizone immediately topped up to the mark with water and mix. the pH of the obtained solution should be of 8.5−9.0. After 5 min, but not later than 30 min, measure the optical density of the solution on a photoelectrocolorimeter with an orange filter in the cell with thickness of the absorbing layer 3 cm, or on the spectrophotometer at a wavelength of 600 nm in a cuvette with a thickness of absorbing layer 1 cm. Solution comparison the solution serves as the reference experiment.
2.4.2.2. Construction of calibration curve
In six of the seven volumetric flasks with a capacity of 100 cmis placed 0,5; 0,75; 1,0; 1,5; 2,0 and 2,5 cm
of a standard solution of copper. To all flasks add 5 cm
of nitric acid, diluted 1:1, 10 cm
of a solution of citrate of ammonium and further analyze as described in section
Solution comparison is the solution not containing copper.
2.4−2.4.2.2. (Changed edition, Rev. N 1).
3. GRAVIMETRIC, ELECTROLYTIC METHOD OF DETERMINING COPPER WITHOUT SEPARATING THE TIN
3.1. The essence of the method
The method is based on masking of tin in the form of soluble fluoride complex, separation of copper by electrolysis, weighing evolved at the cathode precipitate of copper and the determination of the residual content of copper in the electrolyte by atomic absorption spectrometry or photometric method with the use of cuprizone. This simpler method described in sec. 2, but with its application excludes the possibility of subsequent determination of tin, Nickel, and iron.
3.2. Apparatus, reagents and solutions
Installation of electrolysis.
The electrodes are platinum according to GOST 6563.
Atomic absorption spectrometer with a source of radiation for copper.
Photoelectrocolorimeter or spectrophotometer.
Hydrofluoric acid according to GOST 10484.
Boric acid according to GOST 9656, a solution of 50 g/DM.
Sulfamic acid, saturated solution.
Nitric acid according to GOST 4461 and diluted 1:1 and 1:2.
Sulfuric acid according to GOST 4204 and diluted 1:1, 1:4, 1:99.
Bromatologia acid according to GOST 2062.
The mixture of acids to dissolve I; prepared as follows: to 600 cmof nitric acid, diluted 1:1, add 40 cm
hydrofluoric acid, 15 g of boric acid and add water to 1000 cm
. Solution store in a plastic container.
Citric acid according to GOST 10484.*
_____________
* Link to the GOST match the original. — Note the CODE.
The technical rectified ethyl alcohol according to GOST 18300.
Bromine according to GOST 4109.
The mixture for dissolution II; prepared as follows: 9 parts bromatological acid mixed with one part of bromine.
Ammonia water according to GOST 3760 and diluted 1:4.
Hydrazine sulfate according to GOST 5841, a solution of 10 g/DM.
Urea according to GOST 6691, a solution of 10 g/DM.
Ammonium citrate, solution; is prepared as follows: 150 g of citric acid dissolved in 400 cmof water, add with stirring: 100 cm
of concentrated ammonia solution, cool, add another 100 cm
of ammonia, cool and add water to 1000 cm
.
Bis-cyclohexanone-oxalyl-dihydrazone (cuprizone), the solution is prepared as follows: 2.5 g cuprizone dissolved with stirring in 900 cmof water at a temperature of 60−70 °C. After cooling, the solution was filtered into a dark glass jar, add water to volume of 1000 cm
. The solution to fit 10 days.
Copper according to GOST 859, with a mass fraction of copper not less than 99.9%.
Standard solutions of copper.
Solution A, prepared as follows: 0.5 g of copper is dissolved in 10 cmof nitric acid, diluted 1:1, and remove the oxides of nitrogen by boiling, transferred to a volumetric flask with a capacity of 500 cm
, made up to the mark with water and mix.
1 cmof the solution contains 0.001 g of copper.
Solution B is prepared as follows: 10 cmof solution A is placed in a volumetric flask with a capacity of 100 cm
, made up to the mark with water and mix.
1 cmof the solution contains 0,
0001 g of copper.
3.3. Analysis
3.3.1. The sample of bronze with a weight of 1 g was placed in Teflon beaker with a capacity of 250 cm, add 6−8 drops (0.4−0.5 cm
) hydrofluoric acid, 15 cm.
of nitric acid diluted 1:1, cover cover cover made of PTFE and dissolve first without heating and then with heating. The side of the Cup and rinse the cover with water, add 2cm
of a solution of sulfamic acid, dilute with water to 150 cm
and the electrolysis is carried out as specified in clause 2.3.
The electrolyte, after separation of copper is placed in a volumetric flask with a capacity of 250 cm, which previously bring 10 cm
of boric acid, made up to the mark with water, mixed and used to determine the residual copper by atomic absorption spectrometry or photometric method with the use of cuprizone as specified in claim 2.4
.
3.1−3.3. (Changed edition, Rev. N 1).
3.3.2. For the mass concentration of antimony is less than 0.05% of a sample of alloy weighing 1 g is placed in a beaker with a capacity of 300 cm, adding 25 cm
of the mixture to dissolve I and dissolved by careful heating, the solution is kept for 1 h at 90 °C, cooled to room temperature, add 50 cm
of water, ammonia until the appearance of the precipitate, nitric acid, diluted 1:1, to dissolve the solids and in excess of 20 cm
of nitric acid, diluted 1:1, add 10 cm
of a solution of sulfamic acid, dilute with water to 150 cm
and the electrolysis is carried out as specified in clause 2.3.
3.3.3. When the mass fraction of antimony in excess of 0.05% of a sample of alloy weighing 1 g is placed in a beaker with a capacity of 250−300 cmand dissolved in 15 cm
of the mixture for dissolution II on careful heating. After dissolving, the solution was evaporated to dryness, and then another two times add 15 cm
of the mixture for the dissolution of II and the solution evaporated to dryness each time. To the dry residue add 10 cm
of nitric acid and the solution evaporated to a syrupy condition. Then add 10 cm
sulphuric acid diluted 1:1, and the solution was evaporated until a white smoke of sulfuric acid. The residue is cooled, rinse walls of beaker with water and again evaporated until a white smoke of sulfuric acid.
To the cooled residue add 50 cmof water, heated to dissolve the salts, is cooled and in case of sedimentation on the filter tight filter and washed 3−4 times with sulfuric acid diluted 1:99. The precipitate is discarded, the filtrate is added 10 cm
boiled nitric acid, diluted 1:1, 10 cm
of a solution of sulfamic acid, water to a volume of 100−150 cm
and the electrolysis is carried out as specified in clause 2
.3.
3.3.2,
4. PROCESSING OF THE RESULTS
4.1. Mass fraction of copper () in percentage, in the case of determining the remaining in the electrolyte of copper by atomic absorption spectrometry, calculated by the formula
where — volume of the solution of the electrolyte, cm
;
— the mass of cathode, g;
— the mass of the cathode with segregated copper, g;
— the concentration of copper was found in the calibration schedule, g/cm
;
— the weight of the portion,
4.2. Mass fraction of copper () in percentage, in the case of determining the remaining in the electrolyte of copper by the photometric method, is calculated by the formula
where — volume of the solution of the electrolyte, cm
;
— volume aliquote part of the solution, cm
;
— the mass of cathode, g;
— the mass of the cathode with segregated copper, g;
— the mass of copper was found in the calibration schedule g;
— the weight of the portion,
(Changed edition, Rev. N 1).
4.3. Discrepancies in the results of parallel definitions should not exceed the values of permissible differences (the rate of convergence for
3), specified in the table.
| Mass fraction of copper, % |
|
|
| 50.0 to 80,0 incl. |
0,15 |
0,2 |
| SV. 80,0 |
0,20 |
0,3 |
(Changed edition, Rev. N 2).
4.4. Discrepancies in the results analysis, 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 the values given in the table.
4.5. Control of accuracy of analysis results is carried out according to State standard samples of tin bronzes, re-approved by GOST 8.315, in accordance with GOST 25086.
4.4, 4.5. (Added, Rev. N 2).
