Combined generator/separator. Part 2. Stibine generation combined with flow injection for the determination of antimony in metal samples by atomic emission spectrometry
Abstract
Application of a new continuous hydride generator to the determination of antimony in metals by flow injection is described. A modified hydride generator/gas–liquid separator has been designed. The detection limit for antimony is 7.5 ng cm–3 for a 0.5 cm3 sample. For solutions containing 200 ng cm–3 of antimony, the relative standard deviation is 0.9%. Reduction of antimony(V) to antimony(III) is effected by off-line pre-reduction with L-cysteine. L-Cysteine also accelerates the tetrahydroborate(III) reaction and reduces interferences from transition elements and, with the exception of selenium, other hydride-forming elements. Results are reported for the determination of antimony in iron and copper samples.