Substoichiometric extraction of chromium(III) with 2-picolinic acid into n-butanol

A substoichiometric radiochemical extraction procedure has been designed for the estimation of trace amounts of chromium(III). The method employs the extraction of spiked (⁵¹Cr) chromium by chelation with 2-picolinic acid in n-butanol solvent at pH 4. The interference effects of various closely related foreign ions on the extraction efficiency were found to be negligible, thus establishing the selectivity of the proposed technique over other standard analytical procedures available for the estimation of chromium(III). The validity of this method has been established by successful estimation of chromium present in various certified alloys. Investigations have been made to understand the parameters controlling the extraction of chromium(III).