Determination of iron by atomic absorption spectrometry after synergistic extraction of the iron(III)-5,5′-methylene-disalicylohydroxamate-tributyl phosphate complex

Abstract

The synergistic extraction of iron(III) in isobutyl methyl ketone with a mixture of 5,5′-methylenedisalicylohydroxamic acid (MEDSHA) and tributyl phosphate (TBP) has been studied by atomic absorption spectrometry (AAS). From the results it is concluded that the extracted species probably has the composition 2:3:2 (Fe^III:MEDSHA:TBP). Using this reagent an extraction-AAS method for the determination of iron at sub µg ml^–1 levels has been developed. The recommended method has been applied satisfactorily to the determination of iron in petroleum crudes, ores and synthetic samples.