GOST 13047.4-2002

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  ГОСТ 13047.4-2002

GOST 13047.4−2002 Nickel. Cobalt. Methods for determination of cobalt in Nickel

GOST 13047.4−2002

Group B59

INTERSTATE STANDARD

NICKEL. COBALT

Methods for determination of cobalt in Nickel

Nickel. Cobalt. Methods for determination of cobalt in nickel

ISS 77.120.40*
AXTU 1732

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* In the Index «National standards» in 2012
OKS 77.120.40 and 77.120.70. — Note the manufacturer’s database.

Date of introduction 2003−07−01

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 No. 21 dated may 30, 2002)

The adoption voted:

3 Resolution of the State Committee of the Russian Federation on standardization and Metrology from September 17 2002 N 334-St inter-state standard GOST 13047.4−2002 introduced as the national standard of the Russian Federation from July 1, 2003

4 REPLACE GOST 13047.6−81

5 REISSUE. March 2006

1 Scope

This standard specifies the spectrophotometric and atomic absorption methods for the determination of cobalt when the mass proportion of from 0.001% to 1.0% in primary Nickel GOST 849* and Nickel powder according to GOST 9722.
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* On the territory of the Russian Federation the document is not valid. Standards 849−2008, here and hereafter. — Note the manufacturer’s database.

2 Normative references

The present standard features references to the following standards:

GOST 61−75 acetic Acid. Specifications

GOST 123−98* Cobalt. Specifications
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* On the territory of the Russian Federation the document is not valid. Valid GOST 123−2008, here and hereafter. — Note the manufacturer’s database.

GOST 199−78 Sodium acetate 3-water. Specifications

GOST 849−97 Nickel primary. Specifications

GOST 3118−77 hydrochloric Acid. Specifications

GOST 4461−77 nitric Acid. Specifications

GOST 5457−75 Acetylene, dissolved and gaseous. Specifications

GOST 9722−97 Nickel Powder. 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 20015−88 Chloroform. Specifications

GOST 27067−86 Ammonium radamisty. 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 500 nm of a solution of complex compounds of cobalt with nitroso-R-salt after a preliminary extraction of its compounds with the thiocyanate of ammonium and diantipyrylmethane.

4.2 measuring instruments, auxiliary devices, materials, reagents, solutions

Spectrophotometer or photoelectrocolorimeter, which provides measurements in the wavelength range of 490−540 nm.

Instrument providing measurements in the region of pH 5−6.

Nitric acid according to GOST 4461, if necessary, purified by distillation, or according to GOST 11125, diluted 1:1.

Hydrochloric acid according to GOST 3118 or, if necessary, according to GOST 14261, solution molar concentration of 5 mol/DM.

Ascorbic acid of the Pharmacopoeia [1], the solution of the mass concentration of 0.1 g/cm.

Acetic acid according to GOST 61, diluted 1:1, and the solution molar concentration of 0.2 mol/DM.

Ammonium radamisty according to GOST 27067, solution mass concentration of 0.4 g/cm.

Sodium acetate according to GOST 199, solution mass concentration of 0.5 g/cmand the solution molar concentration of 0.2 mol/DM.

Buffer solution: mix 150 cmof acetic acid molar concentration of 0.2 mol/DMand 850 cmof a solution of sodium acetate and a molar concentration of 0.2 mol/DM, add acetic acid diluted 1:1, or a solution of sodium acetate and the mass concentration of 0.5 g/cmto obtain a pH of the solution is between 5.2 and 5.4.

Diantipyrylmethane in [2], solution of the mass concentration of 0.02 g/cmin chloroform.

Chloroform according to GOST 20015 or [3].

Nitroso-R-salt [4], the solution of the mass concentration of 0.001 g/cm.

Cobalt GOST 123.

Cobalt solutions of known concentration.

The solution And the mass of cobalt concentration 0.001 g/cm: in a glass or flask with a capacity of 250 cmis placed a portion of the cobalt ground 1,0000 g, pour 25−30 cmof nitric acid, diluted 1:1 was dissolved, the solution was evaporated to a volume of 7−10 cm, the solution was transferred into a measuring flask with volume capacity of 1000 cm, cooled, poured 50 cmof nitric acid, diluted 1:1, made up to the mark with water.

Solution B mass concentration of cobalt 0.0001 g/cm: in a volumetric flask with a capacity of 100 cmis taken as 10 cmof solution A, pour 10 cmof nitric acid, diluted 1:1, made up to the mark with water.

Solution of mass concentration of cobalt 0,00001 g/cm: in a volumetric flask with a capacity of 100 cmis taken as 10 cmof a solution, pour 5 cmof nitric acid, diluted 1:1, made up to the mark with water.

4.3 Preparation for analysis

To build a calibration curve in beakers or flasks with a capacity of 100 cmis taken 1,0; 2,0; 4,0; 6,0; 8,0; 10,0 cmsolution, pour 0.5 cmof acetic acid diluted 1:1, then do as specified in 4.4.2.

The mass of cobalt in solutions for calibration curve is 0,00001; 0,00002; 0,00004; 0,00006; 0,00008; 0,00010 G.

The light absorption values of solutions and their corresponding masses of cobalt build a calibration curve taking into account light absorption of the solution prepared without the introduction of a solution of cobalt.

4.4 analysis

4.4.1 In a glass or flask with a capacity of 250 cmis placed a portion of the sample weight in accordance with table 1.


Table 1 Conditions of preparation of sample solution

The sample is dissolved by heating in 15−20 cmof nitric acid, diluted 1:1, evaporated the solution to a volume of 7−10 cm.

When the mass fraction of cobalt in excess of 0.01% solution was transferred to volumetric flask with a capacity of 100 cm, made up to the mark with water in a glass with a capacity of 100 or 150 cmaliquote selected part of the volume in accordance with table 1.

To the solution, or part of it aliquotes poured 10 cmof hydrochloric acid, evaporated to dryness. Treatment with hydrochloric acid is repeated. To the residue poured 5cmof hydrochloric acid molar concentration of 5 mol/DM5 cmof water, heated to dissolve the salts, and cooled.

The solution was transferred to a separatory funnel with a capacity of 100 cm, flow 10 cmof a solution of ascorbic acid, incubated for 1−2 min, pour 10 cmof a solution of ammonium Rodenstock, top up with water to 50 cm, flow 10 cmsolution and extracted diantipyrylmethane 1 min. After separation of phases the organic phase was drained into another separatory funnel with a capacity of 100 cm, and the aqueous phase poured 10 cmof the solution diantipyrylmethane, repeat the 1 min extraction, the organic phases are combined, and the water — drop.

To the organic phase poured 15 cmbuffer solution and shake the funnel for 1 min. the Organic phase was drained into another separating funnel, the aqueous phase is poured into the beaker or flask with a capacity of 100 cm. To the organic phase again poured 15 cmbuffer solution and shake the separating funnel for 1 min. the Organic phase discarded and the aqueous phase combined.

The joint solution is poured 0.5 cmof acetic acid diluted 1:1, evaporated to a volume of 10−15 cm.

4.4.2 the solution is poured 5 cmof a solution of sodium acetate and the mass concentration of 0.5 g/cm, boiled for 2−3 min, poured 10 cmof the solution, nitroso-R-salt, boil for 2−3 min, poured 10 cmof nitric acid, diluted 1:1, boiled for 1 min. the Solution was cooled, transferred to a volumetric flask with a capacity of 100 cmand then filled to the mark with water.

After 25−30 min. measure the light absorption of the sample solution and the reference experiment on the spectrophotometer at a wavelength of 500 nm or photoelectrocolorimeter in a region of wavelengths of 490−540 nm, using the solution comparison solution, prepared as described in section 4.3, without the introduction of a solution of cobalt.

The mass of cobalt in solutions found by the calibration schedule.

4.5 Processing the analysis results

Mass fraction of cobalt in the sample in % is calculated by the formula

, (1)

where is the mass of cobalt in the sample solution, g;

 — the mass of cobalt in the solution in the reference experiment, g;

 — weight of sample, g;

 — the dilution factor of the sample solution.

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 2.


Table 2 — Standards for monitoring and error analysis method

Percentage

5 Atomic absorption method

5.1 Method of analysis

The method is based on measurement at a wavelength of 240,7 nm absorption of resonant radiation by the atoms of cobalt, produced as a result of atomization upon introduction of the sample solution into the flame acetylene-air.

5.2 measurement Means, auxiliary devices, materials, reagents, solutions

Atomic absorption spectrophotometer measurements in the flame acetylene-air.

Lamp with hollow cathode for the excitation of spectral lines of cobalt.

Acetylene gas according to GOST 5457.

Filters obestochennye [5] or other medium density.

Nitric acid according to GOST 4461, if necessary, purified by distillation, or according to GOST 11125, diluted 1:1, 1:9, 1:19.

Nickel powder according to GOST 9722 or standard sample of Nickel with the prescribed mass fraction of cobalt is not more than 0.001%.

Cobalt GOST 123.

Cobalt solutions of known concentration.

The solution And the mass of cobalt concentration 0.001 g/cmprepared as described in 4.2.

Solution B mass concentration of cobalt 0.0001 g/cmprepared as described in 4.2.

5.3 Preparation for assay

5.3.1 calibration curve For 1 in determining the mass fraction of cobalt, 0.01% to beakers or flasks with a capacity of 250 cmis placed hitch weight 5,000 g samples of carbonyl Nickel powder or standard sample of Nickel with the prescribed mass fraction of cobalt. The number of batches must match the number of points of calibration curve, including Supervisory experience.

Sample the sample is dissolved by heating to 50−60 cmof nitric acid, diluted 1:1. 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 10−15 cm, 40−50 cm, pourwater, heated to boiling, cooled, transferred to volumetric flasks with a capacity of 100 cm.

In the flask is taken 0,5; 1,0; 2,0; 3,0; 4,0; 5,0 cmof solution B in the flask with the solution in the reference experiment, a solution of cobalt is not introduced, made up to the mark with water and measure the absorbance as indicated in 5.4.2.

The mass of cobalt in solutions for the calibration is 0,00005; 0,00010; 0,00020; 0,00030; 0,00040; 0,00050 G.

5.3.2 For the calibration curve 2 in determining the mass fraction of cobalt from 0.01% to 0.05% in beakers or flasks with a capacity of 250 cmis placed hitch weight 1,000 g samples of carbonyl Nickel powder or standard sample of Nickel with the prescribed mass fraction of cobalt. The number of batches must match the number of points of calibration curve, including Supervisory experience.

Sample the sample is dissolved by heating in 15−20 cmof nitric acid, diluted 1:1, and act, as specified in 5.3.1.

The mass of cobalt in solutions for the calibration specified in 5.3.1.

5.3.3 calibration curve For 3 when determining the mass fraction of cobalt from 0.05% to 0.5% in volumetric flasks with a capacity of 100 cmtaken at 10 cmof the solution in the reference experiment, prepared as described in 5.3.2, enter 0,5; 1,0; 2,0; 3,0; 4,0; 5,0 cmof solution B into one of the flasks with a solution of the reference experiment, a solution of cobalt is not introduced, made up to the mark with water and measure the absorbance as indicated in 5.4.

The mass of cobalt in solutions for the calibration specified in 5.3.1.

5.4 analysis

5.4.1 In a glass or flask with a capacity of 250 cmis placed a portion of the sample weight in accordance with table 3.


Table 3 — Conditions of preparation of sample solution

A sample weight of 5,000 g was dissolved with heating to 50−60 cm, and weight 0,500−1,000 g in 15−20 cmof nitric acid, diluted 1:1, respectively is evaporated to a volume of 15−20 cmand 5−7 cm, 40−50 cm, pourwater, heated to boiling, cooled, transferred the solution into a volumetric flask with a capacity of 100 cm.

When the mass fraction of cobalt in excess of 0.5% in volumetric flask with a capacity of 100 cmis taken aliquot part of the solution by volume in accordance with table 3 and topped to the mark with nitric acid, diluted 1:19.

5.4.2 Measure the absorbance of the sample solution and respective solutions for calibration at a wavelength of 240,7 nm, slit width is not more than 1.0 nm at least two times, sequentially inserting them into a flame, 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 5.3.

The values of absorption solutions for the calibration and corresponding masses of cobalt build calibration graphs.

The value of absorbance of sample solution find the mass of cobalt in the calibration schedule in accordance with table 3.

5.5 Processing of analysis results

Mass fraction of cobalt in the sample in % is calculated by the formula

, (2)

where is the mass of cobalt in the sample solution, g;

 — dilution factor of sample solution;

 — 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 2.