DETERMINATION OF NICKEL IN NATURAL-WATER, SEDIMENT AND BIOLOGICAL-MATERIAL BY ADSORPTIVE STRIPPING VOLTAMMETRY

This paper deals with an electrochemical stripping analysis of nickel in which preconcentration is achieved by the adsorption of nickel - dimethyl glyoxime complex on a mercury electrode surface. Experimental optimum conditions were determined in the studies. The supporting electrolyte was (0.1 M NH4OH+NH4Cl Buffer), pH 9.2 containing ammonium citrate and 5 x 10(-4) M DMG. After preconcentration by adsorption at -0.7 v (vs Ag/AgCl) a differential pulse polargraph was used for monitoring the stripping process. Addition of citrate before the addition of ammonia buffer prevents hydrolysis of Fe and Al generally present in the sample. The technique was applied for the determination of nickel in tap water, sea water, animal tissue and sediment.