Mercury speciation by electrochemical separation and cold-vapour atomic absorption spectrometry

Abstract

Mercury speciation in aqueous solutions containing inorganic mercury and methylmercury has been demonstrated using electrochemical separation prior to determination by cold-vapour atomic absorption spectrometry. Approximately 95% of the inorganic mercury was electro-deposited on a Pt electrode at –0.1 V, whereas for methylmercury –0.2 V or even more negative potentials were required. Organic mercury was determined by NaBH₄ reduction after electrochemical separation. Inorganic mercury was determined in the original solution by SnCl₂ reduction.