Determination of Iodate in Salt Samples with Amperometric Detection at a Molybdenum Oxide Modified Electrode

Autor: Luis Kosminsky, Mauro Bertotti
Rok vydání: 1999
Předmět:
Zdroj: Electroanalysis. 11:623-626
ISSN: 1521-4109
1040-0397
DOI: 10.1002/(sici)1521-4109(199907)11:9<623::aid-elan623>3.0.co;2-a
Popis: A method for the amperometric determination of iodate in a flow injection configuration is described. The electroreduction of the analyte occurs at a glassy carbon disk electrode modified by a molybdenum oxide layer electrochemically deposited, the film acting as an efficient electrocatalyst for the mass transport controlled reduction of iodate. The sensor is applied to the determination of iodate in a wall-jet cell coupled to a flow injection apparatus after convenient deoxygenation of the carrier solution. The linear response of the sensor is extended from 10×10–6 mol L–1 to 10×10–3 mol L–1 iodate with a limit of detection (signal-to-noise=2) of 6×10–6 mol L–1. The repeatability of the method for injections of a 50×10–6 mol L–1 iodate solution was 6 % (n = 22). Interference from other oxidant anions (nitrate, nitrite and perchlorate) was not noticeable, whereas bromate interferes at concentrations up to 10 times that of iodate. The method was used in the determination of the iodate content in commercial salt samples.
Databáze: OpenAIRE