Kinetics and Mechanistic Studies of Ru(III) Catalyzed Oxidation of p-Hydroxy Benzoic Acid by Sodium N-chloro-p-toluene Sulphonamide in Acidic Media

Abstract

Kinetics studies of the oxidation of p-hydroxy benzoic acid by sodium N-chloro-p-toluene sulphonamide (chloramine-T or CAT) have been carried out in aqueous perchloric acid medium at 35 °C. The reaction follows almost similar kinetics, being first order with respect to chloramine-T, p-hydroxy benzoic acid and Ru(III). The reaction exhibits inverse first order depedence on the concentration of medium [HClO4]. Variation of ionic strength by adding NaClO4 have no significant effect on the reaction rate. The addition of p-toluene sulphonamide, which is one of the reaction products, had no significant effect on the reaction rate. Thermodynamic parameters were computed by studying the reactions at different temperature (303-318 K). The rate laws derived are in excellent agreement with the experimental results. A mechanism consistent with the above kinetic result has been suggested.