Separation of traces of indium from gram amounts of tellurium, mercury, and cadmium by cation-exchange chromatography on a single column

Traces and also larger amounts of indium can be separated from gram amounts of tellurium, mercury, and cadmium in a single-column procedure by cation-exchange chromatogprahy on a column containing 5 g of AG50W-X8 resin and determined very accurately. Mercury and tellurium pass through the column during adsorption from 0,5M-nitric acid containing enough bromide to complex mercury, and are elute completely with 0,5M-nitric acid. Cadmium is eluted with 0,2M-hydrobromic acid containing 40% acetone. The strongly retained indium finally is elute with 1,0M-hydrochloric acid. Separations are very sharp and quantitative. Amounts of 9,8μg have been separated from 2 g of a synthetic mixture simulating a TMC semiconductor alloy, and determined by atomic absorption spectrometry with a coefficient variation of about 1%. The sensitivity of the method is about 0,2μg indium when flame atomic absorption is used for determination. Relevant elution curves and the results for the analyses of synthetic mixtures containing from about 2μg to 10 mg amounts of indium are presented