高纯铟样品经盐酸溶解、阳离子交换树脂分离并将试液蒸发浓缩后,用石墨炉原子吸收光谱法测定其中的痕量镍。以0.7 mol·L-1盐酸溶液作为淋洗液进行离子交换,可把大部分铟基体及样品中痕量的共存离子分离除去,再用3.0 mol·L-1盐酸溶液洗脱镍并收集。镍的质量在300 pg以内与其吸光度呈线性关系,方法的检出限(3s)为15 pg。应用此法分析了3个高纯铟样品,测定值与电感耦合等离子体质谱法测定结果相符,加标回收率在95.2%~118%之间,测定值的相对标准偏差(n=8)在1.2%~18%之间。

The sample of high purity indium was dissolved with hydrochloric acid. After separation with cation-exchange resin, trace amount of nickel in high purity indium was determined by GFAAS. After ion-exchange with 0.7 mol·L-1 hydrochloric acid solution as eluent, trace coexisting ion and most of indium in the sample were separated and removed, then nickel was eluted with 3.0 mol·L-1 hydrochloric acid solution and collected. Linear relationship between values of absorbance and mass of nickel was kept in the range within 300 pg, with detection limit (3s) of 15 pg. Three samples of high purity indium were analyzed by the proposed method, giving results in consistency with values given by ICP-MS, with values of recovery and RSD (n=8) in the ranges of 95.2%-118% and 1.2%-18%, respectively.