Sensitive thermometric catalytic method for the determination of iron(III) based on its catalytic action on the oxidation of sulphanilic acid by sodium periodate

Abstract

Analytical conditions for the thermometric determination of Fe^III were studied. The method is based on the catalytic effect of Fe^III on the oxidation of sulphanilic acid by the periodate ion, with 1,10-phenanthroline as an activator. This direct-injection thermometric method employs very simple instrumentation and its operating range is 50–220 ng ml^–1 with a relative standard deviation of 6.6% and good selectivity.