YS/T 254.1-2011 English PDF (YST254.1-2011)

This Part of YS/T 254 specifies the method for determining the content of beryllium oxide in beryllium concentrate and beryl. This Part is applicable to the determination of beryllium oxide in beryllium concentrate and beryl. The determination range is 6.00%~14.00%. 2 Method summary The test material is melted with potassium hydrofluoride. Beryllium is converted into beryllium fluoride salt. After sulfuric acid fumes and melts, it is converted into beryllium sulfate. Leach with water. Acidify with hydrochloric acid. Use hydrogen peroxide and disodium ethylenediaminetetraacetate to complex impurity elements. In the presence of ammonium acetate, diammonium hydrogen phosphate is used to precipitate beryllium twice at a pH value of 5.2~5.8. The precipitate is burned into beryllium pyrophosphate at 1000??C. Weigh to constant. 3 Reagents 3.1 Potassium hydrofluoride. 3.2 Sulfuric acid (??1.84 g/mL). 3.3 Hydrochloric acid (??1.19 g/mL). 3.4 Hydrogen peroxide (??1.10 g/mL). 3.5 Ammonia (??0.90 g/mL). 3.6 Hydrochloric acid solution (1+3). 3.7 Ammonia (1+1). 3.8 Diammonium hydrogen phosphate solution (132.5 g/L): Weigh 132.5 g of diammonium hydrogen phosphate. Dissolve in 500 mL of water. Filter. Transfer to a YS/T 254.1-2011 www.ChineseStandard.net ? Buy True-PDF ? Auto-delivery. Page 6 of 9 1000 mL volumetric flask. Dilute to volume with water. Mix well. 3.9 Disodium ethylenediaminetetraacetate solution (150 g/L): Weigh 150 g of disodium ethylenediaminetetraacetate. Place in a 400 mL beaker. Add ammonia (3.5) to dissolve (filter if necessary). Add a few drops of methyl red ethanol solution (1 g/L). Neutralize to red color with hydrochloric acid solution (1+1). Add more drops of ammonia (3.7) until it just turns yellow. Transfer to a 1000 mL volumetric flask. Dilute to vo