Simultaneous determination of cobalt and nickel by first-derivative spectrophotometry

Abstract

A method for the simultaneous determination of cobalt and nickel in mixtures by first-derivative spectrophotometry is described. The method is based on the red complexes formed by both metal ions with 1-hydroxy-2-carboxyanthraquinone in alkaline ethanol-water mixtures. The range of application is between 0.75 and 4.5 µg ml^–1 for cobalt and between 0.50 and 3.0 µg ml^–1 for nickel. A statistical evaluation of the experimental results is reported.