Mechanism of Ru(III) catalyzed oxidation of D-sorbitol by acid bromate

Kinetic investigations on Ru(III) catalyzed oxidation of D-sorbitol by acidic solution of potassium bromate in the presence of mercury (II) acetate as scavenger have been carried out in the temperature range of 30-50 degrees C. First order kinetics in the lower concentration range of KBrO3, was observed to tend to zero order at its higher concentrations. The reaction follows zero order kinetics in D-sorbitol and order is one with respect to [Ru (III)]. Increase in [H+] and [Cl-] showed positive effect while addition of sodium perchlorate showed negative effect. Mercury (II) acetate and D2O had insignificant effect on the rate of the reaction. A suitable mechanism in conformity with the kinetic observations has been proposed and the thermodynamic parameters were computed.