HG-AFS Determination of Selenium and Bismuth in Antimony Concentrates

Method of HG-AFS for determination of Se and Bi in antimony concentrates was proposed.The sample was effectively dissolved with aqua regia at 80 ℃ for 45 min,rendering maximum extraction and dissolution of selenium and bismuth from the sample.A limited amount of tartaric acid solution (<2 g·L-1) was added to complex with Sb(Ⅴ) and to keep it in solution.An aliquot of the sample solution (1/10) was taken and conc.HCl was added to make the concentration of HCl to 5-6 mol·L-1.The solution was introduced into the intermittent FI-reactor to generate hydrides of Se and Bi which were determined by AFS.Detection limit (3s/k) of the method was determined and values found were 0.18 μg·L-1 for Se and 0.11 μg·L-1 for Bi.Accuracy and precision of the method were tested by analyzing 2 ore concentrate samples with addition of standard Se and Bi at 2 different concentration levels,values of recovery in the ranges of 97.5%-103.2% and 92.0-96.0% were found for Se and Bi respectively,and values of RSD′s (n=6) found were ranged from 1.4%-2.4% (for Se) and 1.2%-1.7% (for Bi).