化学蒸气发生-电感耦合等离子体原子发射光谱法测定地质样品中痕量金
Chemical Vapor Generation-ICP-AES Determination of Au in Geological Samples
-
摘要: 地质样品经盐酸-硝酸(3+1)混合酸溶解,活性炭分离富集后,于90 ℃用12 g·L-1硼氢化钠溶液(溶于0.5 g·L-1氢氧化钠溶液中)作还原剂,用化学蒸气发生-电感耦合等离子体原子发射光谱法测定其中痕量的金。金的质量浓度在1 500 μg·L-1以内与其发射强度呈线性关系,方法的检出限(3s)为0.59 μg·L-1。方法用于测定2个标准物质(GBW 07289和GBW 07291)中金含量,测定值与认定值相符。Abstract: Geological sample was digested with mixed acid of HCl-HNO3 (3+1), and separated and enriched with activated carbon. Au in the solution obtained was reduced with 12 g·L-1 NaBH4 solution (dissolved in 0.5 g·L-1 NaOH solution) at 90 ℃, and determined by chemical vapor generation-ICP-AES. Linear relationship between values of emission intensity and mass concentration of Au was kept in the range within 1 500 μg·L-1, with detection limit (3s) of 0.59 μg·L-1. The proposed method was used in the determination of Au in 2 standard samples (GBW 07289 and GBW 07291), and the results obtained were in conformity with the certified values.