Heterogeneous photocatalysis: Design and experimental characterization of a new photocatalytic reactor for wastewater treatment

Abstract

The objective of this study is to promote photocatalytic wastewater treatment by proposing a reactor design that employs a catalyst-coated, rotating, corrugated drum to increase the surface area, induce agitation and promote reactant and photon transfer to the surface. Corrugation profiles with surface areas ranging from 405 cm2 to 3650 cm2 were considered---the addition of corrugations improved the phenol degradation rate by up to 200%. Based on an analysis of rotational speed and initial pollutant concentration, the reaction was found to be limited by the kinetics at 20 ppm and 40 ppm, but limited by phenol transfer to the reaction sites at 5 ppm. Finally, Langmuir-Hinshelwood kinetics was applicable with an average phenol adsorption coefficient of 0.120 L/mg and an increasing overall reaction rate constant with surface area. Further studies are necessary for the industrial use of such a reactor design including treatment of wastewater with varying characteristics, reactor design scaling and the applicability of this design for solar-activated applications.