Separation and Preconcentration of Trace Amounts of Nickel in Environmental and Biological Samples by Flotation Using Dimethyl glyoxime

Abstract

A simple and selective method for separation and preconcentration of nickel has been developed. The method is based on the flotation of a complex of nickel and dimethyl glyoxime at the aqueous solution of n-hexane interface. The floated layer was then dissolved in 5 mL of 1 mol L^-1 nitric acid for the subsequent spectrometric determination. The quantitative flotation of the complex was possible in the pH range of 9-12. The method is simple and free from the interference of all cations and anions and has a wide linear range. The procedure was successfully applied to the determination of trace amounts of nickel in well water and waste water in coating plant. The method's accuracy was investigated by using standard reference material alloys (NIST 864) and by spiking the samples with different amounts of Ni²⁺.