Carbon Paste Electrode as a Support for Mercury Film in Potentiometric Stripping Determination of Heavy Metals

Abstract

Carbon paste electrodes containing silicone or paraffin oil as the pasting liquids, preplated with a mercury film, were tested for possible use in potentiometric stripping determination of heavy metals like lead, cadmium and copper. The detailed study has shown that the results are comparable with those obtained with widely used mercury-coated glassy carbon electrode with regard to the linear response at low ppb levels, detection limits, reproducibility, etc. The potentiometric stripping analysis with both electrode materials was used for the determination of lead and copper in a soot sample. No significant differences were found when these results were compared with a reference determination performed by graphite-furnace atomic absorption spectrometry.