GOST 13047.4-2014

• gost-130474-2014.pdf (356.95 KiB)
  ГОСТ 13047.4-2014

GOST 13047.4−2014 Nickel. Cobalt. Methods for determination of cobalt in Nickel

GOST 13047.4−2014

INTERSTATE STANDARD

NICKEL. COBALT

Methods for determination of cobalt in Nickel

Nickel. Cobalt. Methods for determination of cobalt in nickel

ISS 77.120.40

Date of introduction 2016−01−01

Preface

Goals, basic principles and main procedure of works on interstate standardization have been established in GOST 1.0−92 «interstate standardization system. Basic provisions» and GOST 1.2−2009 «interstate standardization system. Interstate standards, rules and recommendations on interstate standardization. Rules of development, adoption, application, renewal and cancellation"

Data on standard

1 DEVELOPED by interstate technical committees for standardization MTK 501 Nickel and MTC 502 «Cobalt"

2 as AMENDED by the Federal Agency for technical regulation and Metrology (Rosstandart)

3 ACCEPTED by the Interstate Council for standardization, Metrology and certification (Protocol of October 20, 2014 N 71-N)

The adoption voted:

4 by Order of the Federal Agency for technical regulation and Metrology of June 24, 2015 N 816-St inter-state standard GOST 13047.4−2014 introduced as the national standard of the Russian Federation from 1 January 2016.

5 REPLACE GOST 13047.4−2002


Information about the changes to this standard is published in the annual reference index «National standards», and the text changes and amendments — in monthly information index «National standards». In case of revision (replacement) or cancellation of this standard a notification will be published in the monthly information index «National standards». Relevant information, notification and lyrics are also posted in the information system of General use — on the official website of the Federal Agency for technical regulation and Metrology on the Internet

1 Scope

This standard specifies the spectrophotometric and atomic absorption methods for the determination of cobalt (at a mass fraction of cobalt from 0,0010% to 1.0%) in the primary Nickel GOST 849 and the Nickel powder according to GOST 9722. As an arbitration method is atomic absorption method.

2 Normative references

This standard uses the regulatory references to the following standards:

GOST 61−75 Reagents. The acetic acid. Specifications

GOST 123−2008 Cobalt. Specifications

GOST 199−78 Reagents. Sodium acetate 3-water. Specifications

GOST 849−2008 Nickel primary. Specifications

GOST 3118−77 Reagents. Hydrochloric acid. Specifications

GOST 4461−77 Reagents. 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 13047.1−2014 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 Reagents. Ammonium radamisty. Specifications

Note — When using this standard appropriate to test the effect of reference standards in the information system of General use on the official website of the Federal Agency for technical regulation and Metrology on the Internet or in the annual information index «National standards» published as on January 1 of the current year, and the editions of the monthly information index «National standards» for the current year. If the reference standard is replaced (changed), when using this standard should be guided by replacing (amended) standard. If the reference standard is cancelled without replacement, then the situation in which the given link applies to the extent that does not affect this link.

3 General requirements and safety requirements

General requirements for methods of analysis used by the quality of distilled water and laboratory glassware and safety at 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 and solutions

Spectrophotometer or photoelectrocolorimeter, which provides measurements in the wavelength range from 490 to 540 nm.

pH meter (ion meter) for measurements in the pH range 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, if necessary, purified by distillation, or according to GOST 14261, solution molar concentration of 5 mol/DM.

Ascorbic acid of the Pharmacopoeia [1]*, solution mass concentration of 0.1 g/cm.
________________
* See Bibliography. — Note the manufacturer’s database.


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 is prepared as follows: 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, the flow of acetic acid diluted 1:1, or a solution of sodium acetate and the mass concentration of 0.5 g/cmto obtain a pH in the range of 5.2 to 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/cmis prepared as follows: a portion of the cobalt with a mass of 1,000 g was placed in a beaker or flask with a capacity of 250 cm, flow 25 to 30 cmof nitric acid, diluted 1:1, dissolved by heating, the solution is evaporated to a volume of 7 to 10 cm, transferred to a measuring flask with volume capacity of 1000 cm, cooled, poured 50 cmof nitric acid, diluted 1:1, and adjusted to the mark with distilled water.

Solution B mass concentration of cobalt 0.0001 g/cmis prepared as follows: into a measuring flask with a capacity of 100 cmtransfer 10 cmof solution A, pour 10 cmof nitric acid, diluted 1:1, and adjusted to the mark with distilled water.

Solution of mass concentration of cobalt 0,00001 g/cmis prepared as follows: into a measuring flask with a capacity of 100 cmtransfer 10 cmof a solution, pour 5 cmof nitric acid, diluted 1:1, and adjusted to the mark with distilled water.

4.3 Preparation for analysis

To build a calibration curve in beakers or flasks with a capacity of 100 cmtransfer 1,0; 2,0; 4,0; 6,0; 8,0 and 10,0 cmsolution, pour 0.5 cmof acetic acid diluted 1:1, then carry out the analysis in accordance with 4.4.2.

The mass of cobalt in the calibration solutions is 0,00001; 0,00002; 0,00004; of 0.00006; and 0,00010 0,00008 g.

According to the obtained values of absorption of the calibration solutions and corresponding mass of cobalt to build a calibration curve taking into account the absorption of the calibration solution, is prepared without introducing a solution containing cobalt.

4.4 analysis

4.4.1 Sample the sample mass depending on the mass fraction of cobalt in accordance with table 1 were placed in a glass or flask with a capacity of 250 cm, flow 15 to 20 cmof nitric acid, diluted 1:1, dissolved by heating, and the solution is evaporated to a volume of 7 to 10 cm.


Table 1 Conditions of preparation of sample solution

When the mass fraction of cobalt in excess of 0.01% solution transferred to a volumetric flask with a capacity of 100 cm, adjusted to the mark with distilled water and transferred to a beaker with a capacity of 100 or 150 cmaliquot part of the solution by volume in accordance with table 1.

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

The solution was transferred to a separatory funnel with a capacity of 100 cm, poured 10 cmof the ascorbic acid solution, kept for 1 to 2 minutes, poured 10 cmof the solution Rodenstock ammonium, distilled water to a volume of 50 cm10 cmsolution and extracted diantipyrylmethane 1 min. After separation of the organic phase solution is poured into another separatory funnel with a capacity of 100 cm, and the aqueous phase poured 10 cmof the solution diantipyrylmethane and repeating the extraction 1 min. the Aqueous phase is discarded and the organic phases combined.

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.

To the aqueous phase poured 0.5 cmof acetic acid diluted 1:1, evaporated to a volume of 10 to 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 adjusted to the mark with distilled water.

Light absorption of the sample solution and the reference experiment measured 25−30 min on a spectrophotometer at a wavelength of 500 nm or photoelectrocolorimeter at a wavelength range from 490 to 540 nm. A solution of comparison, using the solution prepared in accordance with 4.3, without the introduction of a solution containing cobalt.

The value of the light absorption of the sample solution find the mass of cobalt in the calibration schedule.

4.5 Processing the analysis results

Mass fraction of cobalt in the sample X, %, 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;

K — dilution factor of sample solution;

M — weight of sample, g.

4.6 Control of accuracy of analysis results

Control of accuracy of analysis results is carried out according to GOST 13047.1.

The regulations control the precision (limits of repeatability and reproducibility) and the rate control accuracy (expanded uncertainty) of the results of the analysis are shown in table 2.


Table 2 — Requirements of control precision (limits of repeatability and reproducibility) and the rate control accuracy (expanded uncertainty) of the results of the analysis at a confidence probability P=0,95

Percentage

5 Atomic absorption method

5.1 Method of analysis

The method is based on measuring absorption at a wavelength of 240,7 nm resonance radiation by cobalt atoms, the resulting fiery atomization when spraying a solution of the sample in the flame acetylene-air.

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

Atomic absorption spectrometer for 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 filter medium density.

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

Nickel powder according to GOST 9722 or standard sample of Nickel pre-installed (certified) 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/cmat 4.2.

Solution B mass concentration of cobalt 0.0001 g/cmat 4.2.

5.3 Preparation for assay

5.3.1 To construct a calibration chart 1 in determining the mass fraction of cobalt is not more than 0,010% suspension of Nickel powder or standard sample of Nickel with a mass of 5,000 grams are placed into glasses or a flask with a capacity of 250 cm. The number of batches must match the number of points of calibration curve, including Supervisory experience.

The suspension of Nickel powder or standard sample of Nickel is dissolved by heating in a volume of 50 to 60 cmof nitric acid, diluted 1:1. When using the Nickel powder in the solution was filtered through a filter (red or white ribbon), washed two or three times with nitric acid, diluted 1:9. The filter is washed two or three times with hot distilled water. The solution is evaporated to a volume of 10 to 15 cm, flow from 40 to 50 cmof distilled water, heated to boiling, cooled, transferred to volumetric flasks with a capacity of 100 cm.

In the flask transfer 0,5; 1,0; 2,0; 3,0; 4,0 and 5,0 cmof solution B. the flask with the solution in the reference experiment the solution containing cobalt is not poured, adjusted to the mark with distilled water and measure the absorbance in accordance with 5.4.2.

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

5.3.2 For the construction of calibration curve 2 in determining the mass fraction of cobalt from 0.01 to 0.05% suspension of Nickel powder or standard sample of Nickel with a mass of 1,000 g was placed in a beaker or flask with a capacity of 250 cm. The number of batches must match the number of points of calibration curve, including Supervisory experience.

The suspension of Nickel powder or standard sample is dissolved by heating in 15 to 20 cmof nitric acid, diluted 1:1, and act in accordance with 5.3.1.

The mass of cobalt in the calibration solutions is given in 5.3.1.

5.3.3 For construction of calibration curve 3 when determining the mass fraction of cobalt over 0.05% in volumetric flasks with a capacity of 100 cmshift 10 cmof the solution in the reference experiment, prepared in 5.3.2, poured 0,5; 1,0; 2,0; 3,0; 4,0 and 5,0 cmof solution B. In one of the flasks with a solution in the reference experiment the solution containing cobalt is not poured, adjusted to the mark with distilled water and measure the absorbance in accordance with 5.4.2.

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

5.4 analysis

5.4.1 the sample the sample mass depending on the mass fraction of cobalt in accordance with table 3 was placed in a beaker or flask with a capacity of 250 cm.


Table 3 — Conditions of preparation of sample solution

A portion of the sample with a mass of 5,000 g was dissolved with heating in a volume of 50 to 60 cmof nitric acid, diluted 1:1, and the weight of 0,500, or 1,000 g, in the amount of 15 to 20 cmof nitric acid, diluted 1:1, evaporated to a volume of 15 to 20 cmor from 5 to 7 cm, flow from 40 to 50 cmof distilled water, heated to boiling and cooled. The solution was transferred to volumetric flask with a capacity of 100 cmand adjusted to the mark with distilled water.

When the mass fraction of cobalt over 0.05% in a volumetric flask with a capacity of 100 cmstand aliquot part of the solution by volume in accordance with table 3 and adjusted to the mark with nitric acid, diluted 1:19.

5.4.2 absorption of the sample solution and the calibration solutions at a wavelength of 240,7 nm, slit width is not more than 1.0 nm is measured at least two times, sequentially spraying them in the flame acetylene-air, spray rinsed the system with distilled 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 in accordance with 5.3.

According to the obtained values of absorbance of the calibration solutions and their corresponding masses of the cobalt build of the calibration graphs.

The value of absorbance of sample solution find the mass of cobalt in the corresponding calibration chart.

5.5 Processing of analysis results

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

, (2)

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

K — dilution factor of sample solution;

M — weight of sample, g.

5.6 Control of accuracy of analysis results

Control of accuracy of analysis results is carried out according to GOST 13047.1.

The regulations control the precision (limits of repeatability and reproducibility) and the rate control accuracy (expanded uncertainty) of the results of the analysis are shown in table 2.

Bibliography

_______________

*** Valid on the territory of the Russian Federation.