Continuous flow analysis systems for mercury determinations in industrial effluents

A system for continous flow analysis (CFA) is presented, which cad be adapt ed to an atomic absorbtion spectrophotometer (AAS) in order to determine th e mercury from industrial residual waters. The influence;af different opera tional parameters on determination is also discussed. The analytical method is based on reduction with SnCl2 of Hg2+ to elementary mercury, followed b y the extraction of the latter from the liquid phase by an air flow into a flow cell of an AAS. The method sensitivity is very good as sample's with c oncentrations between 0.005-0.04 mu g Hg2+ mL(-1) can be analyzed with a re lative standard deviation of 1.6% and a sample throughput of 15 h(-1).