Powered by Google www.ChineseStandard.net Database: 189759 (9 Jun 2024)

YS/T 252.3-2007 PDF in English


YS/T 252.3-2007 (YS/T252.3-2007, YST 252.3-2007, YST252.3-2007)
Standard IDContents [version]USDSTEP2[PDF] delivered inName of Chinese StandardStatus
YS/T 252.3-2007English110 Add to Cart 0-9 seconds. Auto-delivery. Methods for chemical analysis of nickel matte. Determination of cobalt content. Flame atomic absorption spectrometric method  


Standards related to: YS/T 252.3-2007

YS/T 252.3-2007: PDF in English (YST 252.3-2007)

YS/T 252.3-2007
YS
NONFERROUS INDUSTRY STANDARD
OF THE PEOPLE’S REPUBLIC OF CHINA
ICS 77.120.40
H 13
Replacing YS/T 252.3-1994
Methods for chemical analysis of nickel matte -
Determination of cobalt content - Flame atomic absorption
spectrometric method
ISSUED ON: APRIL 13, 2007
IMPLEMENTED ON: OCTOBER 01, 2007
Issued by: National Development and Reform Commission of PRC
Table of Contents
Foreword ... 3
1 Scope ... 5
2 Method summary ... 5
3 Reagents ... 5
4 Instruments ... 6
5 Analytical procedures ... 6
6 Calculation and expression of analysis results ... 7
7 Precision ... 8
8 Quality assurance and control ... 8
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.
The main drafters of this Part: Liu Haidong, Yu Shengjie, Lv Qingcheng, Lin Xiuying,
Zhao Junfeng, Zhu Yuqiang.
The main verifiers of this Part: Tang Shufang, Yu Li, Mai Libi, Dai Fengying, Zhang
Yongjin.
The National Nonferrous Metals Standardization Technical Committee is responsible
Methods for chemical analysis of nickel matte -
Determination of cobalt content - Flame atomic absorption
spectrometric method
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
3.1 Hydrochloric acid (ρ1.19 g/mL).
3.2 Nitric acid (ρ1.42 g/mL).
3.3 Nitric acid (1 + 1).
3.4 Ammonia (1 + 3).
3.5 Nitric acid-potassium chlorate saturated solution: Dissolve potassium chlorate in
nitric acid (3.2) until saturated.
3.6 Cobalt standard storage solution: Weigh 1.0000 g of metallic cobalt (mass fraction
of cobalt ≥ 99.95%). Slowly add 20 mL of nitric acid (3.3) into a 400 mL beaker. Cover
with a watch glass. Heat at low temperature to completely dissolve. Remove it. Use
water to rinse the watch glass and cup wall. Heat and boil to remove nitrogen oxides.
Remove it. Cool to room temperature. Transfer it into a 1000 mL volumetric flask. Use
water to wash the watch glass and cup wall. Combine the washing liquid into the
volumetric flask. Use water to make the volume reach to the mark. 1 mL of this solution
contains 1 mg of cobalt.
3.7 Cobalt standard solution: Pipette 20.00 mL of cobalt standard storage solution (3.6)
into a 200 mL volumetric flask. Make the volume reach to the mark. 1 mL of this
solution contains 100 μg of cobalt.
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
5.1 Sample
Weigh 0.400 g of specimen, accurate to 0.0001 g.
5.2 Blank test
Do a blank test along with the sample.
5.3 Determination
5.3.1 Place the sample (5.1) in a 400 mL beaker. Moisten it with a small amount of
water. Add 10 mL of hydrochloric acid (3.1). Cover with a watch glass. Dissolve at low
temperature and evaporate to a volume of about 2 mL. Cool it. Add 20 mL of saturated
nitric acid-potassium chlorate solution (3.5). Continue to heat to dissolve and evaporate
to a volume of 2 mL ~ 3 mL. Cool it. Wash the watch glass and cup wall with about 20
......
 
Source: Above contents are excerpted from the PDF -- translated/reviewed by: www.chinesestandard.net / Wayne Zheng et al.