The determination of molybdenum in geological materials by a combined solvent-extraction-atomic-absorption procedure

Abstract

A method is described for the determination by atomic-absorption spectrophotometry of molybdenum, up to the 1000 p.p.m. level, in geochemical samples. After attack with acid, the molybdenum in dilute perchloric acid medium is complexed with benzoin α-oxime and extracted into chloroform. The extract is mixed with nitric and perchloric acids and evaporated to dryness and the residue is dissolved in ammonia solution. The ammonium molybdate formed is dissolved in a solution containing 1 per cent. v/v of perchloric acid plus 0·5 per cent. w/v of ammonium chloride and aspirated into a luminous air-acetylene flame.