Substituted N-hydroxy-NN′-diarylbenzamidines as selective extractants for the spectrophotometric determination of vanadium(V) in the presence of acetic acid or an azide

Abstract

The reactions of 11 newly synthesised N-hydroxy-NN′-diarylbenzamidines (HOA) with vanadium(V), in the presence of acetic acid or an azide, have been studied spectrophotometrically to determine the effect of substituents on the complexing properties of the ligand. The investigations showed the formation of 1 : 2 : 1 [vanadium(V) : HOA: acetic acid] and 1 : 2 : 2 [vanadium-(V) :HOA : azide] complexes in chloroform. Based on the mixed complex formations, simple, rapid, sensitive and selective methods for the spectrophotometric determination of microgram amounts of vanadium(V) have been developed. The methods have been applied to the determination of the vanadium content of BCS steels.