Design and simulation of a photocatalysis reactor for rhodamine B degradation using cobalt-doped ZnO film

This research aims to investigate the simulation of a pilot-scale photocatalytic reactor based on cobalt-doped ZnO films, where the photocatalyst films were initially assessed on a lab scale for the degradation of rhodamine B (RhB) under visible light. ZnO and cobalt-doped ZnO catalyst films were firstly synthesized by means of the spray pyrolysis technique. The catalyst films were then characterized by X-ray diffraction (XRD), scanning electronic microscopy (SEM), and diffuse spectroscopy (EDS) (DRS). The lattice parameters of cobalt-doped ZnO films, as well as their bandgap values and structures, have been computed applying the density functional theory (DFT). Box-Behnken Design (BBD) was used to assess the effect of the main operating parameters (contact time, RhB concentration, and cobalt doping percentage) on the photocatalytic activity that achieved 93% using 10% of cobalt doping ZnO within 120 min. Aspen Plus was used to model and design the photocatalysis process at the pilot scale based on the lab-scale results. The findings of this study suggest that cobalt-doped ZnO films could be effectively used for the photodegradation of organic pollutants and offer potential perspectives on their large-scale application for the treatment of real liquid effluents using solar light.