Spectrophotometric Determination of Trace Amounts of Scandium with Molybdate, Nile Blue and Poly(vinyl alcohol)

Abstract

A sensitive method for the determination of trace amounts of scandium by spectrophotometry is described, based on the formation of the ion associate between scandium(III), molybdate and Nile Blue in the presence of poly(vinyl alcohol). The molar absorptivity at 585nm is 3.59×10⁵dm³ mol^-1 cm^-1. Beer′s law is obeyed over the range 0-2.0μg scandium per 25ml. Optimal conditions for the determination and the interferences from foreign ions are reported. Ten-fold amounts of rare earth elements do not interfere with the determination of scandium, except cerium. The proposed method has been applied successfully for the spectrophotometric determination of scandium in some geological samples.