ANODIC-STRIPPING OF HEAVY-METALS USING A HANGING MERCURY DROP ELECTRODE IN A FLOW SYSTEM

A hanging mercury drop electrode, included in a low deal volume thin l ayer flow cell, has been used for on-line simultaneous determination o f the trace metals Cd, Ph, Cu and Zn. Parameters related either to the flow system or to the differential pulse anodic stripping technique w ere optimized. Internal standard and standard additions quantitation m ethods were tested. Bi was chosen as internal standard and adequate co nditions for the stripping medium were studied. The method was applied to the determination of these metals in algae samples of the north co ast of Spain. The results compared favorably with those obtained by IC P-IMS.