Propylene carbonate extraction of tris(pentan-2,4-dione)-iron(III) from aqueous solution: application to the spectrophotometric determination of iron

Abstract

Orange tris(pentan-2,4-dione)iron(III) is extracted from aqueous solution into propylene carbonate at pH 4·0 to 9·0. Distribution coefficients range from 23·9 to 116, depending on the ionic strength and pH of the aqueous phase. Relative standard deviations of the spectrophotometric methods developed are 1·52 per cent. or less and these methods are applicable to the routine determination of 56 to 391 µg of iron. One of the methods was applied to the determination of iron in wrought aluminium alloy. The importance of using non-toxic solvents in analytical chemistry is emphasised.