Kinetics and Mechanism of Mn (II) Catalyzed Oxidation of D-Arabinose and D-Xylose by Chromium (VI) Ions in Perchloric Acid Medium

Abstract

The present paper describes the kinetics and mechanism of oxidation of D-arabinose and D-xylose by acidic solution of Chromium (VI) in the presence of Mn (II). First-order dependence of the reaction rate was observed on sugars, HClO4 at low concentrations and a zero-order observed for sugars at a higher concentration. First-order kinetics with respect to Mn (II) throughout its variation was observed in the oxidation of both sugars. The Cl− and ionic strength effect was found to be negligible. Arrhenius activation energy and other thermodynamic activation parameters have been evaluated and lend further support to the proposed mechanism. Formic acid and erythronic acid were reported as the product of oxidation for both sugars.