GOST 1293.3-83
GOST 1293.3−83 lead-antimony Alloys. Methods for determination of bismuth (with Amendments No. 1, 2)
GOST 1293.3−83*
______________________
* 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 bismuth
Lead-antimony alloys. Methods for the determination of bismuth
AXTU 1709*
________________
* Changed the wording, Rev. N 1.
Valid from 01.01.84
to 01.01.89*
_______________________________
* 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 703
REPLACE GOST 1293.3−74
MADE: the Change in N 1, approved and put into effect by the Decree of the USSR State Committee for standards from
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 and photometric methods for determination of bismuth at a mass fraction of bismuth from 0.01 to 0.15% 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
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 bismuth 223,1 nm.
2.2. Apparatus, materials and reagents
Atomic absorption spectrophotometer of any brand.
Air, compressed under a pressure of 2·10-6·10
PA (2−6 ATM), depending on equipment.
Acetylene in cylinders GOST 5457−75.
Tartaric acid according to GOST 5817−77.
Nitric acid GOST 4461−77.
A mixture of acids: 100 g of tartaric acid dissolved in 500 cmof water, add 250 cm
of nitric acid and adjusted with water to 1000 cm
.
Bismuth GOST 10928−90, brand Ви0.
(Changed edition, Rev. N 2).
2.3. Preparation for assay
2.3.1. Preparation of standard solutions of bismuth
Solution a: 1,000 g of bismuth dissolved in 20 cmof a mixture of acids. After cooling, the solution is transferred to a volumetric flask with a capacity of 100 cm
, made up to the mark with water and mix.
1 cmof the solution contains 1 mg of bismuth.
Solution B: 10 cmsolution And transferred to a volumetric flask with a capacity of 100 cm
, made up to the mark with water and mix.
1 cmof the solution contains 100 ág of bismuth.
(Changed edition, Rev. N 2).
2.3.2. To build a calibration curve in six of the seven volumetric flasks with a capacity of 100 cmmake 1, 3, 5, 8, 10 and 15 cm
standard solution B, corresponding to 1, 3, 5, 8, 10 and 15 µg/cm
of bismuth. To all flasks add 20 cm
of a mixture of acids was adjusted to the mark with water and mix.
2.4. Analysis
A portion of the alloy weight 1,0000 g is placed in a conical flask with a capacity of 250 cm, flow 20 cm
of the mixture of acids 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 bismuth 223,1 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/cm, or in the mode «absorption» method «limiting solutions» or 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 indications for the test solution and the two standard solutions, one of which gives large and the other smaller readings compared to the readings for the test 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 the solution, µg/cm
,
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 readings of a dial or digital device.
Mass fraction of bismuth () in percent is calculated by the formula
where is the concentration of bismuth in the sample solution, µg/cm
;
— the concentration of bismuth in solution in the reference experiment, µ g/cm
;
— the volume of the analyzed solution, 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 allowable absolute values of the differences given in the table.
| Mass fraction of bi, % | The limit of error of the results of the analysis |
The discrepancy between the results of parallel measurements |
The discrepancy between the results of the analysis |
| From 0.010 to 0.020 incl. | 0,001 |
0,002 | 0,002 |
| SV. 0,020 «0,050 « | 0,003 |
0,004 | 0,004 |
| «0,050» 0,10 « | 0,006 |
0,008 | 0,008 |
| «To 0.10» to 0.15 « | 0,02 |
0,02 | 0,02 |
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 the table, under the following conditions: the discrepancy between the results of parallel measurements does not exceed the permissible, the results of the monitoring of the accuracy of positive analysis.
(Changed edition, Rev. N 2).
3. PHOTOMETRIC METHOD
3.1. The essence of the method
The method is based on dissolving the alloy in a mixture of nitric and tartaric acids, the formation of colored complex compounds of bismuth with thiourea and measuring the optical density of the solution in the region of wavelengths 400−450 nm on the photoelectrocolorimeter or at 413 nm on the spectrophotometer.
(Changed edition, Rev. N 1).
3.2. Apparatus, materials and reagents
Photoelectrocolorimeter or spectrophotometer.
Nitric acid GOST 4461−77 and diluted 1:1.
Tartaric acid according to GOST 5817−77.
Acids mixture: 200 g of tartaric acid dissolved in 500 cmof water, add 250 cm
of nitric acid and dilute with water to 1000 cm
.
Thiourea according to GOST 6344−73, a solution of 50 g/DM, freshly prepared.
Lead nitrate according to GOST 4236−77, a solution of 80 g/DM.
Bismuth GOST 10928−90, brand Ви0.
(Changed edition, Rev. N 2).
3.3. Preparation for assay
3.3.1. Preparation of a standard solution of bismuth
0,1000 g of bismuth dissolved in 50 cmof a solution of nitric acid, boil to remove oxides of nitrogen, cooled, 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 bismuth.
(Changed edition, Rev. N 2).
3.3.2. To build a calibration curve in six of the seven volumetric flasks with a capacity of 100 cmpour 1, 2, 4, 6, 8 and 10 cm
of a standard solution of bismuth, which corresponds to 0,1; 0,2; 0,4; 0,6; 0,8 and 1,0 mg of bismuth. In the seventh flask standard solution of bismuth is not administered. To all flasks add 20 cm
of a solution of nitrate of lead, 20 cm
of a mixture of acids, 20 cm
solution of thiourea, made up to the mark with water and mix. Measure the optical density of the solutions in the region of wavelengths of 400−450 nm. Solution comparison is water.
According to the obtained values of optical density of the solutions (minus the optical density of the solution, which has not imposed a standard solution of bismuth) and their corresponding grades of bismuth build the calibration graph.
(Changed edition, Rev. N 1).
3.4. Analysis
A portion of the alloy weight 1,0000 g when the mass fraction of bismuth from 0.01 to 0.05% or 0,5000 g when the mass fraction of bismuth from 0.05 to 0.15% is placed in a conical flask with a capacity of 250 cmand dissolved by heating in 20 cm
of a mixture of acids. After dissolution, the solution was cooled, added 40 cm
of water, transferred to a volumetric flask with a capacity of 100 cm
, add 20 cm
of a solution of thiourea, made up to the mark with water and mix. Measure the optical density of the solutions in the region of wavelengths of 400−450 nm. Solution comparison is water.
A lot of bismuth find the calibration schedule.
(Changed edition, Rev. N 1, 2).
3.5. Processing of the results
3.5.1. Mass fraction of bismuth () in percent is calculated by the formula
where is the mass of bismuth in the sample solution, found by calibration schedule, mcg;
— the mass of bismuth in the solution in the reference experiment, was found in the calibration schedule, mcg;
— the weight of the portion of alloy,
3.5.2. The discrepancy between the results of parallel determination (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 allowable absolute values of the differences given in the table.
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 the table, under the following conditions: the discrepancy between the results of parallel measurements does not exceed the permissible, the results of the monitoring of the accuracy of positive analysis.
(Changed edition, Rev. N 2).
