Oxidative Degradation of D-Sucrose by Employing N-Bromosuccinimide as Oxidant: A Micellar Kinetic and Catalytic Study

Abstract

The oxidation of D-sucrose by N-bromosuccinimide and surfactants as a catalyst in the presence of acidic medium was studied at 45°C (± 0.1°C). The rate studies were made under pseudo-first-order conditions with an excess of sugar over the oxidant. In this aim was followed a mechanistic and structural investigation based on a micellar kinetic study. The kinetics revealed first-order dependence on N-bromosuccinimide and fractional-order dependence on D-sucrose. Variations of mercuric acetate had an insignificant effect on reaction rate. The solvent effect revealed that negative dielectric effect. The influence of salts on the reaction rate was also studied. Succinimide and sulfuric acid inhibit the rate. The rate constant (kW), binding constants (KS+KO), and corresponding activation parameters (Ea, ΔH#, ΔS#, and ΔG#) were determined. A detailed mechanism with associated reaction kinetics is presented and discussed. Differences among the oxidation rates of the D-sucrose in the presence of various surfactants discussed qualitatively in terms of Berezin's model, nature of surfactants, and charge of surfactants.