Intrinsic kinetic model with variable light intensity of the emerging pollutants degradation in a photocatalytic differential reactor with immobilized TIO2: Experiments and CFD

Abstract

Heterogeneous photocatalysis is an alternative to mineralizing emerging pollutants. The present study focuses on the kinetic model of salicylic acid photocatalytic degradation in an aqueous solution as a function of pollutant concentration and light intensity. The intrinsic kinetic model parameters were determined using a differential photocatalytic reactor with immobilized TiO2 based on experiments and numerical simulations. Five degradation experiments with different light intensities were performed for a turbulent flow rate of 4.7 L/min and salicylic acid concentration of 20 mg/L. Light intensities used for the kinetic experiments were obtained by computational fluid dynamics (CFD) simulation using the radiation transfer equation that was pre-validated. The TiO2 immobilized method presents low leaching of the catalyst and good degradation efficiency. The intrinsic kinetic model showed to be first-order both for the pollutant concentration and for the light intensity and can be applied in simulation to optimize and design photocatalytic reactors.