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Page : 9 pages
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Release : 2024-06-04
Category : Technology & Engineering
ISBN : 8210379456XXX
YS/T 252.4-2007 Translated English of Chinese Standard (YS/T 252.4-2007, YST252.4-2007) by https://www.chinesestandard.net Pdf
This standard specifies the method for determination of copper content in high nickel matte. This standard is applicable to the determination of copper content in high nickel matte. Measuring range: 6% ~ 55%. 2 Method summary The sample is decomposed with hydrochloric acid and nitric acid-potassium chlorate saturated solution. The ammonium bifluoride is used to mask the iron and the solution is controlled at pH3.5 ~ pH4. Potassium iodide is added, to cause the copper to precipitate copper iodide and precipitate an equal amount of iodine. Use the starch solution as an indicator; use sodium thiosulfate standard titration solution to indirectly determine the amount of copper. 3 Reagents 3.1 Ammonium bifluoride. 3.2 Potassium iodide. 3.3 Ammonia water (¦Ñ0.90 g/mL). 3.4 Hydrochloric acid (¦Ñ1.19 g/mL). 3.5 Nitric acid (¦Ñ1.42 g/mL). 3.6 Nitric acid (1 + 1). 3.7 Sulfuric acid (1 + 1). 3.8 Urea saturated solution. 3.9 Potassium sulfate solution (100 g/L). YS/T 252.4-2007 www.ChineseStandard.net ? Buy True-PDF ? Auto-delivery. Page 6 of 9 3.10 Nitric acid-potassium chlorate saturated solution: Dissolve potassium chlorate in nitric acid (3.5) until saturated. 3.11 Starch solution (5 g/L). 3.12 Copper standard solution: Accurately weigh 1.0000 g of metallic copper (mass fraction of copper ¡Ý 99.95%). Place it in a 400 mL beaker. Add 20 mL of nitric acid (3.6). Dissolve at low temperature and evaporate to a viscous state. Cool it. Add 5 mL of sulfuric acid (3.7). Heat until a lot of white smoke comes out. Cool it slightly. Add water to boil to dissolve the salts. Cool to room temperature. Pipette it into a 1000 mL volumetric flask. Use water to make the volume reach to the mark. 1 mL of this solution contains 1.0 mg of co