DETERMINATION OF MERCURY IN ZINC ORE CONCENTRATE REFERENCE MATERIALS USING FLOW-INJECTION AND COLD-VAPOR ATOMIC-ABSORPTION SPECTROMETRY

A flow-injection, cold-vapor atomic absorption spectrophotometric meth od was developed for the determination of trace amounts of mercury in a proposed zinc ore concentrate Standard Reference Material (SRM 113b) . The samples were digested with nitric and hydrochloric acids in clos ed Teflon digestion vessels. The experimental details for sample prepa ration and the flow injection method are discussed. The effect of matr ix and various acid concentrations on the extraction and subsequent an alysis of mercury were also studied. The method has a detection limit of 0.08 mug Hg/g in the sample. A certified reference material (CZN-1) was analyzed and the results obtained agreed well with the certified value.