Abstract
A method for the continuous introduction of volatile hydrides and mercury into a helium microwave-induced plasma using a hydrogen separation membrane has been developed. Upon passing the evolved gaseous species through a hollow-fiber membrane, hydrogen and water vapor were removed, while the hydrides and mercury were left and introduced into the plasma. The detection capabilities of a tangential flow torch and two capillary discharge tube torches were compared. The effects of the carrier and auxiliary gas flow rates, hydrogen separation temperature and volume of buffer tank were investigated for germanium. The detection limits for Ge, As, Sb, Sn and Hg were 0.04, 0.32, 6.1, 1.4 and 0.50ng/ml, respectively. The relative standard deviation of the emission intensities of Ge at 5ng/ml was 1.4% (n=7).
