GFAAS Determination of Trace Nickel in High Purity Indium with Ion-Exchange Separation

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.