GOST 13047.22-2002
INTERSTATE STANDARD
NICKEL. COBALT
METHODS FOR DETERMINATION OF THALLIUM IN NICKEL
THE INTER-STATE COUNCIL
FOR STANDARDIZATION, METROLOGY AND CERTIFICATION
Minsk
Preface
1 DEVELOPED by Interstate technical committees for standardization MTK 501 Nickel and MTC 502 «Cobalt», JSC «Gipronikel ' Institute»
INTRODUCED by Gosstandart of Russia
2 ADOPTED by the Interstate Council for standardization, Metrology and certification (Protocol № 21 dated may 30, 2002)
The adoption voted:
| The name of the state | The name of the national authority for standardization |
| The Republic Of Azerbaijan | Azgosstandart |
| The Republic Of Armenia | Armastajad |
| The Republic Of Belarus | Gosstandart Of The Republic Of Belarus |
| Georgia | Gosstandart |
| The Kyrgyz Republic | Kyrgyzstandard |
| The Republic Of Moldova | Moldovastandart |
| Russian Federation | Gosstandart Of Russia |
| The Republic Of Tajikistan | Tajikstandart |
| Turkmenistan | The MDCSU «Turkmenstandartlary» |
| The Republic Of Uzbekistan | Standards |
| Ukraine | Gosstandart Of Ukraine |
3 Resolution of the State Committee of the Russian Federation for standardization and Metrology dated 17 September 2002 No. 334-St inter-state standard GOST 13047.22−2002 introduced directly as state standard of the Russian Federation from July 1, 2003
4 INTRODUCED FOR THE FIRST TIME
The CONTENTS
1 Scope 2 Normative references 3 General requirements and safety requirements 4 a spectrophotometric method 4.1 Method of analysis 4.2 measuring instruments, auxiliary devices, materials, reagents, solutions 4.3 Preparation for analysis 4.4 analysis 4.5 Processing the analysis results 4.6 accuracy Control analysis 5 Atomic absorption method 5.1 Method of analysis 5.2 measurement Means, auxiliary devices, materials, reagents, solutions 5.3 Preparation for assay 5.4 analysis 5.5 Processing of analysis results 5.6 Control of accuracy of analysis Annex A Bibliography |
GOST 13047.22−2002
INTERSTATE STANDARD
NICKEL. COBALT
Methods for determination of thallium in Nickel
Nickel. Cobalt.
Methods for determination of thallium in nickel
Date of introduction 2003−07−01
1 Scope
This standard specifies the spectrophotometric and atomic absorption methods for the determination of thallium for the mass concentration of 0.00005% to 0,0010% in primary Nickel GOST 849.
2 Normative references
The present standard features references to the following standards:
GOST 849−97 Nickel primary. Specifications
GOST 2603−79 Acetone. Specifications
GOST 3118−77 hydrochloric Acid. Specifications
GOST 4147−74 Iron (III) chloride 6-water. Specifications
GOST 4461−77 nitric Acid. Specifications
GOST 5457−75 Acetylene, dissolved and gaseous. Specifications
GOST 5955−75 Benzene. Specifications
GOST 6552−80 orthophosphoric Acid. Specifications
GOST 9722−97 Nickel Powder. Specifications
GOST 10157−79 Argon gaseous and liquid. Specifications
GOST 10929−76 Hydrogen peroxide. Specifications
GOST 11125−84 nitric Acid of high purity. Specifications
GOST 13047.1−2002 Nickel. Cobalt. General requirements for methods of analysis
GOST 14261−77 hydrochloric Acid of high purity. Specifications
GOST 18337−95 Thallium. Specifications
3 General requirements and safety requirements
General requirements for methods of analysis and safety requirements when performing work — according to GOST 13047.1.
4 a spectrophotometric method
4.1 Method of analysis
The method is based on measuring light absorption at a wavelength of 600 nm of a solution of complex compounds of thallium with crystal violet, extracted with benzene from the environment of phosphoric acid.
4.2 measuring instruments, auxiliary devices, materials, reagents, solutions
Spectrophotometer or photoelectrocolorimeter, which provides measurements in the wavelength range 580 — 610 nm.
Acetylene according to GOST 5457.
Nitric acid according to GOST 4461, if necessary, purified by distillation, or according to GOST 11125, diluted 1:1 and 1:19.
Hydrochloric acid according to GOST 3118 or, if necessary, according to GOST 14261, diluted 1:1.
Orthophosphoric acid according to GOST 6552, diluted 1:4.
Hydrogen peroxide according to GOST 10929.
Iron (III) chloride 6-water according to GOST 4147, solution mass concentration of 0.25 g/cm3.
Acetone according to GOST 2603.
Benzene according to GOST 5955.
Crystal violet [1], the solution of the mass concentration of 0.002 g/cm3.
Thallium GOST 18337.
Solutions of known concentration of thallium.
The solution And the mass concentration of thallium 0.0001 g/cm3: in a glass with a capacity of 100 cm3 is placed a portion of the thallium mass 0,1000 g, pour 15 — 20 cm3 nitric acid, diluted 1:1, are dissolved in a boiling water bath, cool, transfer the solution into a measuring flask with volume capacity of 1000 cm3, pour 100 cm3 of nitric acid, diluted 1:1, and topped to the mark with water.
Solution B is the mass concentration of thallium 0,00001 g/cm3: in a volumetric flask with a capacity of 100 cm3 is taken 10 cm3 of solution A, pour 10 cm3 of nitric acid, diluted 1:1, made up to the mark with water.
Solution of the mass concentration of thallium 0,000002 g/cm3: in a volumetric flask with a capacity of 100 cm3 is taken in 20 cm3 of a solution, pour 10 cm3 of hydrochloric acid diluted 1:1, made up to the mark with water.
4.3 Preparation for analysis
To build a calibration curve in glasses with a capacity of 100 or 150 cm3 taken 0,5; 1,0; 2,0; 3,0; 4,0; 5,0 cm3 of solution, put them in a boiling water bath and evaporate the solutions to dryness. To the dry residue poured 2 — 3 cm3 of hydrochloric acid and evaporated again in a boiling water bath to dryness. To the dry residue pour 25 cm3 of phosphoric acid diluted 1:4.5 cm3 of water, dissolve the precipitate and then do as specified in 4.4.
The weight of thallium in the solutions for calibration curve is 0,000001; 0,000002; 0,000004; 0,000006; 0,000008; 0,000010 G.
The light absorption values of solutions and their corresponding masses of thallium to build a calibration curve taking into account the light absorption values of the calibration solution, is prepared without introducing a solution of thallium.
4.4 analysis
In a glass with a capacity of 250 cm3 place the weighed sample mass of 3,000 g when determining the mass fraction of thallium is not more than 0,0003%, and a mass of 1,000 g in determining the mass fraction of thallium more than 0,0003%, flow 30 — 40 or 15 — 20 cm3 of nitric acid, diluted 1:1, evaporated to a volume of 7 — 10 cm3, pour 5 10 cm3 of hydrochloric acid, not allowing to boil, transfer the beaker on a boiling water bath and evaporate the solution to dryness. To the dry residue poured 5 — 10 cm3 of hydrochloric acid and again evaporated in a water bath to dryness. Treatment with hydrochloric acid is repeated.
To the dry residue pour 25 cm3 of phosphoric acid diluted 1:4.5 cm3 of water and dissolved salt. To a solution flow of 1 cm3 of a solution of iron (III) chloride, 0.5 cm3 of hydrogen peroxide and incubated for 40 min.
The solution was transferred to a separatory funnel with a capacity of 100 cm3, the glass is washed with 10 cm3 of water, poured 0.5 cm3 of a solution of crystal violet, 20 cm3 of benzene and shake the funnel for 1 min. after 10 — 15 min the aqueous lower phase is drained and discarded, and the organic phase, dry pipette select aliquot part of the solution volume of 15 cm3 in a dry volumetric flask with a capacity of 25 cm3, made up to the mark with acetone.
Measure the light absorption of the sample solution and the reference experiment on the spectrophotometer at a wavelength of 600 nm or photoelectrocolorimeter in the wavelength range 580 — 610 nm, using a solution of comparison, the mixture of 15 cm3 of benzene and 10 cm3 of acetone.
The weight of thallium in the sample solution found by the calibration schedule.
4.5 Processing the analysis results
Mass fraction of thallium in the sample of X %, is calculated by the formula
(1)
where Mx is the mass of thallium in the sample solution, g;
MK — mass of thallium in solution in the reference experiment, g;
M — the weight of the portion of the sample,
4.6 accuracy Control analysis
Control of metrological characteristics of the results of the analysis carried out according to GOST 13047.1. Standards monitoring and error analysis method are given in table 1.
Table 1 — Standards for monitoring and error analysis method
Percentage
| Mass fraction of thallium | The permissible discrepancy between two parallel definitions d2 | Permissible discrepancies in the results of three parallel measurements d3 | The allowable discrepancy of the two results of analysis D | The error analysis method D |
| 0,00005 | 0,00003 | 0,00004 | Of 0.00006 | 0,00004 |
| 0,00010 | Of 0.00006 | 0,00007 | 0,00012 | 0,00008 |
| 0,00030 | 0,00010 | 0,00012 | 0,00020 | 0,00015 |
| 0,00050 | 0,00015 | 0,00018 | 0,00030 | 0,00020 |
| 0,0010 | 0,0002 | 0,0003 | 0,0004 | 0,0003 |
5 Atomic absorption method
5.1 Method of analysis
The method is based on measuring absorption at a wavelength of 276,8 nm resonance radiation by atoms of thallium generated by the electrothermal atomization of the sample solution.
5.2 measurement Means, auxiliary devices, materials, reagents, solutions
Atomic absorption spectrophotometer measurements with electrothermal atomization, the correction non-selective absorption and the automated flow of the solution into the atomizer.
Lamp with hollow cathode for the excitation of spectral lines of thallium.
Argon gas according to GOST 10157.
Filters obestochennye [2] or other medium density.
Nitric acid according to GOST 4461, if necessary, purified by distillation, or according to GOST 11125, diluted 1:1 and 1:9.
Nickel powder according to GOST 9722 or standard sample of Nickel with the prescribed mass fraction of thallium is not more than 0,00005%.
Thallium GOST 18337.
Solutions of known concentration of thallium.
The solution And the mass concentration of thallium 0.0001 g/cm3 prepared as described in 4.2.
Solution B is the mass concentration of thallium 0,00001 g/cm3 prepared as described in 4.2.
Solution of the mass concentration of thallium 0,000001 g/cm3: in a volumetric flask with a capacity of 100 cm3 is taken 10 cm3 of a solution, pour 10 cm3 of nitric acid, diluted 1:1, and topped to the mark with water.
5.3 Preparation for assay
5.3.1 calibration curve For 1 in determining the mass fraction of thallium is not more than 0,0003% in beakers or flasks with a capacity of 250 cm3 place hitch weight 1,000 g sample of Nickel powder or standard sample of Nickel with the prescribed mass fraction of thallium. The number of batches must match the number of points of calibration curve, including Supervisory experience.
The sample flow 15 — 20 cm3 of nitric acid, diluted 1:1 and dissolved by heating. When using the Nickel powder in the solutions were filtered through filters (red or white ribbon), washed 2 — 3 times with nitric acid, diluted 1:9, the filters are washed 2 — 3 times with hot water. The solutions were evaporated to a volume of 5 — 7 cm3, flow 40 — 50 cm3 of water, heated to boiling, cooled, transferred to volumetric flasks with a capacity of 100 cm3.
In the flask is taken 0,5; 1,0; 1,5; 2,0; 3,0 cm3 of the solution in the flask with the solution in the reference experiment, a solution of thallium is not administered, made up to the mark with water and then measure the absorbance as indicated in 5.4.
The weight of thallium in the solutions for the calibration is 0,0000005; 0,0000010; 0,0000015; 0,0000020; 0,0000030 G.
5.3.2 For the calibration curve 2 in determining the mass fraction of thallium in excess of 0.0003% in beakers or flasks with a capacity of 250 cm3 place the sample weighing 0,500 g sample of Nickel powder or standard sample of Nickel with the prescribed mass fraction of thallium. The number of batches must match the number of points of calibration curve, including Supervisory experience. The sample is dissolved as specified in 5.3.1, the solutions were transferred to volumetric flasks with a capacity of 100 cm3, injected 1,0; 2,0; 3,0; 4,0; 5,0 cm3 of a solution In one of the flasks with a solution of the reference experiment, a solution of thallium is not administered, made up to the mark with water and then measure the absorbance as indicated in 5.4.
The weight of thallium in the solutions for the calibration is 0,000001; 0,000002; 0,000003; 0,000004; 0,000005 g.
5.4 analysis
In a glass or flask with a capacity of 250 cm3 place the weighed sample mass of 1,000 g in determining the mass fraction of thallium is not more than 0,0003% by weight 0,500 g in determining the mass fraction of thallium more than 0,0003%, pour 15 — 20 cm3 of nitric acid, diluted 1:1, dissolve while heating, evaporate to a volume of 7 — 10 cm3, was transferred to a volumetric flask with a capacity of 100 cm3, cooled and topped to the mark with water.
Measure the absorbance of the sample solution and respective solutions for calibration at a wavelength of 276,8 nm, slit width is not more than 1.0 nm with a correction non-selective absorption in the current of argon at least two times, sequentially inserting them into the atomizer. Depending on the type of spectrophotometer select the optimal volume of the solution from 0.005 to 0.050 cm3 or the optimal time of an aerosol spray from 5 to 50 C. wash the system with water, check the zero point and the stability of the calibration curve. To check the zero point solution is used, the appropriate control experience, prepared as described in section 4.3.
Selection of optimal temperature regimes for the atomizer is carried out individually for the used spectrophotometer on solutions for calibration.
Recommended operating conditions of the atomizer shown in table 2.
Table 2 — operating conditions of the atomizer
| The name of the stage | Temperature, °C | Time |
| Drying | 100 — 150 | 2 — 45 |
| Ashing | 400 — 600 | 10 — 20 |
| Atomization | 1800 — 2200 | 4 — 5 |
The values of absorption solutions for the calibration and corresponding mass of thallium build calibration graphs.
The value of absorbance of sample solution find the mass of thallium on the appropriate calibration schedule.
5.5 Processing of analysis results
Mass fraction of thallium in the sample of X %, is calculated by the formula
(2)
where Mx is the mass of thallium in the sample solution, g;
M — the weight of the portion of the sample,
5.6 Control of accuracy of analysis
Control of metrological characteristics of the results of the analysis carried out according to GOST 13047.1. Standards monitoring and error analysis method are given in table 3.
Table 3 — Standards for monitoring and error analysis method
Percentage
| Mass fraction of thallium | The permissible discrepancy between two parallel definitions d2 |
Permissible discrepancies in the results of three parallel measurements d3 | The allowable discrepancy of the two results of analysis D | The error analysis method D |
| 0,00005 | 0,00002 | 0,00003 | 0,00004 | 0,00003 |
| 0,00010 | 0,00003 | 0,00004 | Of 0.00006 | 0,00004 |
| 0,00030 | 0,00005 | Of 0.00006 | 0,00010 | 0,00007 |
| 0,00050 | 0,00007 | 0,00008 | 0,00014 | 0,00010 |
| 0,00100 | 0,00012 | 0,00014 | 0,00020 | 0,00015 |
APPENDIX A
(reference)
Bibliography
[1] THE 6−09−5924−89 Crystal violet
[2] THE 6−09−1678−95* Filters obestochennye (red, white, blue ribbon)
* Valid on the territory of the Russian Federation.
Key words: Nickel, thallium, chemical analysis measurement tools, solution, reagent, sample, mass fraction, calibration curve, the result of the analysis, accuracy, standards of control
