CATALYTIC EFFICIENCY OF NiS/Al2S3 NANOPARTICLE WITH VALACYCLOVIR HYDROCHLORIDE BY CHLORAMINE-T IN ACID SOLUTION: DECIPHERING THE KINETICS AND MECHANISM

An electrochemical method was employed to synthesize NiS/Al2S3 nanoparticles, with Na2S serving as the conductive salt, at room temperature and ambient pressure. The synthesized nanoparticle showed an average crystalline size of 5nm with a hexagonal crystal structure. A combination of XRD, SEM, EDX, and FTIR techniques provided insights into the material’s size, shape, and chemical composition. The data reveals the adverse catalytic property of the nanoparticle. The synthesized NiS/Al2S3 nanoparticle was used as a catalyst to study the degradation of Valacyclovir (VCL) by N-Chloro-p-toluensulfonamide (CAT) in low pH solution at 298K. A detailed analysis of the reaction stoichiometry and oxidation products was performed for both nano-catalyzed and non-nano-catalyzed reactions. The reaction rate’s influence on [CAT] is unimolecular, while the proportionality to [VCL] is fractional-order, for both nano-catalyzed and non-nano-catalyzed reactions. The influence of hydrogen ion concentration on reaction kinetics differs between the non-nano-catalyzed and nano-catalyzed reactions, with an inverse proportionality to a fractional power observed for the former and a non-integer order dependence observed for the latter. The reaction rate is not appreciably affected due to the accumulation of the resulting compound. A negligible negative correlation between the permittivity constant and reaction rate was found for both cases. The independence of the reaction rate on ionic strength implies that non-ionic species play a crucial role in the rate-limiting step. No evidence of free radical intermediates was found, and kinetic studies at different temperatures enabled the calculation of thermodynamic parameters. A plausible mechanism was proposed to explain the observed kinetic parameters, and rate laws were formulated for both catalyzed and nano-catalyzed reactions.