Methods for chemical analysis of nickel matte - Determination of nickel content - Dimethylglyoxime gravimetric method
1 Scope
This part specifies a method for determining the nickel content in nickel matte.
This part is applicable to the determination of nickel content in nickel matte, with a determination range of 20%–80%.
2 Principle
The test portion is decomposed by hydrochloric acid and nitric acid-potassium chlorate saturated solution. In ammonia medium, nickel reacts with dimethylglyoxime to generate red nickel dimethylglyoxime precipitate to separate from other impurity elements. The precipitate is filtered, washed and dried to constant mass, and then the nickel content is calculated. As for the nickel content in the mixed filtrate, nickel is extracted with chloroform at pH6.5 to separate from other impurities and then determined by dimethylglyoxime spectrophotometry before correction.
3 Reagents
3.1 Hydrochloric acid (ρ 1.19g/mL).
3.2 Hydrochloric acid (1+1).
3.3 Hydrochloric acid (1+24).
3.4 Nitric acid (ρ 1.42 g/mL).
3.5 Nitric acid (1+1).
3.6 Sulphuric acid (ρ 1.83 g/mL).
3.7 Aqueous ammonia (1+1).
3.8 Chloroform.
3.9 Nitric acid-potassium chlorate saturated solution: Dissolve potassium chlorate in nitric acid (3.4) until saturation.
3.10 Potassium sodium tartrate solution (200 g/L), filter before use.
3.11 Ammonium acetate solution (200 g/L), filter before use.
3.12 Sodium thiosulfate solution (200 g/L), filter before use.
3.13 Dimethylglyoxime ethanol solution (10 g/L), filter before use.
3.14 Dimethylglyoxime-sodium hydroxide solution (10 g/L): Dissolve 15 g of sodium hydroxide in 100 mL of water, leave the solution to cool to room temperature and then dissolve 1 g of dimethylglyoxime in the solution and mix well.
Foreword i
1 Scope
2 Principle
3 Reagents
4 Apparatus
5 Analytical procedures
6 Calculation and expression of analysis results
7 Precision
8 Quality assurance and control
