四苯砷氯盐酸盐重量法测定粗铼化合物中铼

粗铼化合物高铼酸、铼酸钾、铼酸铵是湿法冶金新工艺从铂铼废催化剂中回收铼得到的中间产品,生产要求对铼含量进行准确测定。取含铼约100 mg的高铼酸、铼酸钾、铼酸铵样品于烧杯中,加入水至总体积为50 mL,加热溶液或溶解样品,加入0.2 mL过氧化氢氧化铼为铼、5 mL EDTA溶液掩蔽干扰离子、45 mL氨水、10 mL四苯砷氯盐酸盐溶液沉淀铼,沉淀于烘箱中110 ℃烘除水分1 h,恒重,建立了四苯砷氯盐酸盐重量法测定粗铼化合物高铼酸、铼酸钾和铼酸铵中铼的方法。实验表明:于选定条件下,铼与四苯砷氯盐酸盐沉淀完全,铂等20种共存离子不干扰测定。将方法分别用于3个管理样品、6个实际样品中45.30～84.34 g/L、40.93%～69.42%铼的测定,测定值与参考值基本一致,相对标准偏差(RSD,n=7～11)为0.023%～0.085%,加标回收率为99.8%～100.1%。

Determination of rhenium in raw rhenium compounds by tetraphenylarsonium hydrochloride gravimetry

Raw rhenium compounds were the intermediate products of rhenium recovered from spent platinum-rhenium catalyst by new technology of hydrometallurgy, including perrhenic acid, potassium rhenate and ammonium rhenate. The accurate determination of rhenium content was required in production process.The perrhenic acid, potassium rhenate and ammonium rhenate sample containing about 100 mg of rhenium was transferred into beaker, respectively. After adding water to 50 mL, the solution was heated to dissolve the sample. Then, 0.2 mL of hydrogen peroxide was added to oxidize rhenium to rhenium, which was precipitated by adding 5 mL of EDTA solution for masking the interference ions, 45 mL of ammonia water and 10 mL of tetraphenylarsonium hydrochloride solution. The precipitate was dried in oven at 110 ℃ for 1 h to remove the moisture until constant weight. The determination method of rhenium in raw rhenium compounds including perrhenic acid, potassium rhenate and ammonium rhenate by tetraphenylarsonium hydrochloride gravimetry was established. The experimental results showed that rhenium could be fully precipitated by tetraphenylarsonium hydrochloride under selected conditions. Twenty coexisting ions such as platinum did not interfere with the determination. The proposed method was applied to the determination of rhenium (45.30-84.34 g/L, 40.93%-69.42%) in three control samples and six actual samples. The found results were basically consistent with the reference values. The relative standard deviations (RSD, n=7-11) were between 0.023% and 0.085%. The recoveries were between 99.8% and 100.1%.