YS/T 252.3-2007Methods for chemical analysis of nickel matte. Determination of cobalt content. Flame atomic absorption spectrometric method (English PDF)

Foreword

YS/T 252 "Methods for chemical analysis of nickel matte" is divided into five parts:

YS/T 252.1 Methods for chemical analysis of nickel matte - Determination of nickel

content - Dimethylglyoxime gravimetric method

YS/T 252.2 Methods for chemical analysis of nickel matte - Determination of iron

content - Sulfosalicylic acid photometric method

YS/T 252.3 Methods for chemical analysis of nickel matte - Determination of cobalt

content - Flame atomic absorption spectrometric method

YS/T 252.4 Methods for chemical analysis of nickel matte - Determination of cobalt

content - Sodium thiosulphate titrimetric method

YS/T 252.5 Methods for chemical analysis of nickel matte - Determination of sulfur

content - Combustion-neutralization titrimetric method

This Part is Part 3.

This Part replaces YS/T 252.3-1994 "Determination of cobalt content by sulfosalicylic

acid photometric method". Compared with YS/T 252.3-1994, this Part mainly has the

following changes:

- CHANGE the measurement method from sulfosalicylic acid photometric method

to flame atomic absorption spectrometry;

- ADJUST the measurement range from 0.30% ~ 1.50% to 0.1% ~ 2%;

- ADD the repeatability limits, supplementing quality assurance and control terms.

This Part was proposed by AND shall be under the jurisdiction of the National Technical

Committee for Standardization of Nonferrous Metals.

Responsible drafting organization of this Part: Jinchuan Group Co., Ltd.

Participated drafting organization of this Part: Beijing General Research Institute of

Mining and Metallurgy, Guangzhou Nonferrous Metals Research Institute.

1 Scope

This Part specifies the method for determination of cobalt content in high nickel matte.

This Part is applicable to the determination of cobalt content in high-nickel matte.

Measuring range: 0.1% ~ 2%.

2 Method summary

Decompose the sample with hydrochloric acid, nitric acid-potassium chlorate saturated

solution. Use air-acetylene flame in hydrochloric acid (2 + 98) medium, to measure the

absorbance at the wavelength of 240.7 nm of atomic absorption spectrometer, after

subtracting the background. Calculate the cobalt content according to the standard curve

method.

3 Reagents

4 Instruments

Atomic absorption spectrometer (with background subtraction function), equipped with

cobalt hollow cathode lamp.

Under the best working conditions of the instrument, those that can meet the following

indicators can be used.

Characteristic concentration: In a solution that is basically consistent with the

measurement test solution, the characteristic concentration of cobalt shall not be greater

than 0.06 µg/mL.

Precision: Use the highest concentration standard solution to make 10 measurements of

the absorbance; the standard deviation shall not exceed 1.0% of the average absorbance.

Use the lowest concentration standard solution (not the "zero" standard solution) to

make 10 measurements of the absorbance; the standard deviation shall not exceed 0.5%

of the average absorbance of the highest concentration standard solution.

Linearity of the working curve: Divide the working curve into five equal segments

according to concentration. The ratio -- of the absorbance difference of the highest

segment to the absorbance difference of the lowest segment -- shall not be less than

0.85.

5 Analytical procedures