Mechanistic study of iodide catalysed oxidation of l-glutamic acid by cerium(IV) in aqueous sulphuric acid medium

A minute quantity (10−6 mol dm−3) of iodide catalysed oxidation of l-glutamic acid by CeIV has been studied in H2SO4 and SO42− media. The reaction was first order each in [CeIV] and [I−]. The order with respect to [l-glutamic acid] was less than unity (0.71). Increase in [H2SO4] decreased the reaction rate. The added HSO4− and SO42− decreased the rate of reaction. The added product, succinic acid, had no effect on the reaction rate, whereas added CeIII retarded the reaction. The ionic strength and dielectric constant did not have any significant effect on the rate of reaction. The active species of oxidant was Ce(SO4)2. A suitable mechanism was proposed. The activation parameters were determined with respect to the slow step of the mechanism. The thermodynamic quantities were also determined and discussed.