An improved method for the determination of arsenic in steel

Abstract

The steel sample is dissolved in hydrochloric and nitric acids and the arsenic reduced with hypophosphorous acid. The resulting arsenic trichloride is extracted with chloroform and then re-extracted from the organic phase with water. The aqueous solution of arsenic is allowed to react with ammonium molybdate, and the molybdoarsenate is reduced to molybdenum blue. The method is applicable to high purity iron, carbon steels, low alloy and highly alloyed steels including rustless, stainless and tool steels.