ICP-AES Determination of Indium in Tungsten Ore after Extraction with Butyl Acetate

The content of indium in tungsten ore was determined by ICP-AES. The sample was fused at high temperature with Na2O2 as flux. Indium in sample was enriched and separated by extraction with butyl acetate from 5.5 mol·L-1 HBr medium, and then back-extracted to aqueous phase with 6 mol·L-1 HCl solution. Analytical spectral line of 230.606 nm for In was chosen for the analysis. Linear relationship between values of emissive intensity and mass concentration was kept in the range of 0.1-100 mg·L-1, with detection limit (3s) of 0.03 mg·L-1. The proposed method was applied to the analysis of standard samples, and results obtained were consistent with the certified values, with RSD′s (n=6) in the range of 3.2%-7.2%.