Oxidation of Some Water-Soluble Anionic Polyelectrolytes. Oxidation of Carboxymethyl Cellulose Polysaccharide by Hexacholroiridate(IV) in Aqueous Percholorate Solutions. A Kinetic and Mechanistic Appr
The kinetics and mechanism of hexacholroiridate(IV) oxidation of carboxymethyl cellulose (CMC) in aqueous solutions at a constant ionic strength of 0.1 mol dm鈥? has been investigated spectrophotometrically. The experimental results showed first-order dependence in [IrCl6]2鈥?/sup> and fractional first-order kinetics with respect to CMC concentration. An inverse-fractional first-order in [H+] was observed. A kinetic evidence for the formation of 1:1 intermediate complex was revealed. The reaction kinetics seems to be of considerable complexity where one chloride ion from hexacholoiridate(IV) oxidant may act as a bridging ligand between the oxidant and the substrate into the formed intermediate complex. The ionic strength was found to have a negligible influence on the reaction rates. The kinetic parameters have been evaluated, and a tentative reaction mechanism consistent with the kinetic results is discussed.