Kinetic Modelling of the catalytic oxidation of 2-(methylmercapto)-benzothiazole under mild conditions

Abstract

2-(Methylmercapto)-benzothiazole oxidation was performed over Copper modified zeolites. The microporous materials were synthesized by the hydrothermal crystallization method and later modified with metal incorporation by wet impregnation. The solid catalysts were characterized by means of X-ray diffraction, surface area determinations, inductively coupled plasma emission spectrophotometry, temperature programmed reduction and Fourier transformed infrared spectroscopy. Reaction parameters (Copper content, nature of the solvent, hydrogen peroxide concentration, reaction time, catalyst mass and reaction temperature) were evaluated to reach the optimum reaction conditions. Kinetic modelling and kinetic parameter estimation based on experimental kinetic data were included. Cu(II) species were confirmed as the active sites of the catalysts, being Y zeolite the optimal support. Thus, Fenton-like reaction mechanism with reactive oxygen species as hydroxyl and hydroperoxyl radicals (HO, HO2) was confirmed. Reactions rates constants values and activation energy were determined by non-linear least-square parameter estimation. Also, homogeneous catalytic system was evaluated in order to discard diffusional limitations.