Estimation of mercury in industrial effluents by substoichiometric extraction with diphenyl carbazone

A method of quantification of mercury (II) content in industrial effluents based on the principle of substoichiometric isotope dilution analysis has been reported. It involves the extraction of spiked mercury (Hg-203) with substoichiometric amounts of diphenyl carbazone in toluene media. Extraction condition has been optimized at pH 6.5 by pH variation study and slope ratio analysis data shows 1:2 composition of metal:ligand of the extracted metal-complex. The effects of various closely related foreign ions on the extraction process are critically studied and it is found that extraction was almost free from any interferences of the diverse ions adopting the present technique. Results are extrapolated to the determination of metal content in industrial effluents.