Determination of molybdenum(VI) in sea water by densitometry after enrichment as the tiron complex on a thin layer of anion-exchange resin

Abstract

A rapid, simple and sensitive method for the determination of trace amounts of molybdenum(VI) in sea water has been developed, based on the enrichment of molybdenum(VI) as a yellow Tiron complex by a thin layer of anion-exchange resin followed by densitometric scanning of the thin layer. Except for chromium(VI), vanadium(V) and titanium(IV), other trace elements and major constituents of sea water did not affect the determination of molybdenum(VI). The interferences from chromium(VI) and vandium(V) were effectively reduced by the addition of ascorbic acid. Titanium in the hydroxide form, which is actually present in sea water, has no interfering effect on the determination of molybdenum(VI). The concentration of dissolved molybdenum(VI) in Japan Sea water was found to be 11.5 µg l^–1 with a relative standard deviation of 1.1%.