Abstract

KINETIC AND MECHANISTIC STUDY OF OXIDATION OF ACETYL SALICYLIC ACID BY CHLORAMINE-T USING RU(III) AS CATALYST IN AQUEOUS ALKALINE MEDIUM

Amrita Srivastava* and Neha Agarwal

ABSTRACT

The mechanistic study of Ru (III) catalysed oxidation of Acetyl Salicylic acid has been proposed by N-chloro-p-toluenesulphonamide (chloramine-T) in aqueous alkaline medium at 308 K. The oxidation reaction follows first order with respect to [oxidant], first order in [asp], and first order in catalyst. The rate of reaction decreased with increase in the concentration of OH-. The rate also decreased with decreasing dielectric constant of the medium (increasing the % of acetic acid by volume). The variation of ionic strength of the medium had no significant effect on the rate of reaction. The determined shoichiometric ratio was 1:2 ( [Asp] : [CAT] ) and the reaction product was identified by FTIR and UV spectroscopic techniques. The proposed reaction mechanism and derived rate law are consistent with the observed kinetic data. The activation parameters are computed and discussed and thermodynamic quantities are also determined. The probable active species of catalyst and oxidant have been identified.

Keywords: Aspirin, Ru(III) Chloride, Chloramine-T, Kinetics, Oxidation.