SPECTROPHOTOMETRIC DETERMINATION OF VANADIUM IN ILMENITE

A new procedure has been developed for eliminating interference from titanium in the N-benzoyl-N-phenylhydroxylamine procedure for determination of vanadium. After the oxidation of vanadium (IV) with potassium permanganate, vanadium(V)-BPHA complex is extracted into chloroform from sulphuric acid and converted to the chloride form before removal of the original aqueous phase. Coextracted titanium is removed from the isolated organic phase by extracting with a solution of pentasodium tripolyphosphate in 2 M sulphuric acid. Appropriate arrangement of the order of reagent addition avoids reduction of vanadium(V) in the strongly acidic chloride systems. © 1969.