Simultaneous determination of molybdenum and tungsten using a flow injection system and without pre-separation

Abstract

A flow injection system is described for the determination of molybdenum and tungsten, based on their catalytic effects on the reaction of hydrogen peroxide and iodide. Two sample plugs are injected into the same carrier stream sequentially. One is for molybdenum determination and the other is for the sum of molybdenum and tungsten. For molybdenum determination, citric acid solution is simultaneously injected into a parallel carrier stream and merged with the sample plug by using the zone technique. The proposed method has been applied to the determination of molybdenum and tungsten in mineral samples.