An indirect amplification procedure for the determination of vanadium in aluminium alloys by atomic-absorption spectroscopy

Abstract

Vanadium in the range 5 to 50 µg is determined by an amplification procedure in which molybdovanadophosphoric acid (MVPA) is formed and extracted into butan-1-ol after removal of the excess of molybdophosphoric acid by prior extraction with a mixture of chloroform and butan-1-ol. The eleven molybdate ions associated with each vanadium ion in molybdovanadophosphoric acid are determined by direct atomic-absorption spectroscopy in a nitrous oxide-acetylene flame at 313·2 nm. The effect of large excesses of other ions has been investigated, and a procedure has been developed for the separation of interfering ions prior to the determination of vanadium. The sensitivity of the atomic-absorption-indirect amplification procedure (1 per cent. absorption) corresponds to 0·011 µg ml^–1. The procedure has been applied to the determination of vanadium in aluminium.