H2O2 VISUV PHOTOOXIDATION PROCESS FOR TREATMENT OF WATERBORNE HAZARDOUS SUBSTANCES - REACTION-MECHANISM, RATE MODEL, AND DATA FOR TUBULAR FLOW AND FLOW STIRRED-TANK REACTORS/

This paper presents the chemical reaction engineering development of t he H2O2/VisUV photo-oxidation process for treatment of hazardous water borne substances, that occur in groundwater, leachates, and industrial wastewater. Reaction results, on benzene (BNZ), dichlorobenzene (DCB) , trichloroethene (TCE), trichloroethane (TCA), and carbon tetrachlori de (CTC), have been obtained, providing engineering data and models th at can be used to size full-scale equipment. A photochemical flow stir red tank reactor (pcfSTR) and a photo-chemical tubular flow reactor (p cTFR) were used in the experimental work. Two experimental discoveries were made in the course of the work: (1) conventional thermal kinetic s do not apply, the rate controlling variable is the photon flux, and (2) for the photo-chemical reactors used, the pcfSTR was more effectiv e than the pcTFR. The following sub-topics are discussed: reaction mec hanism, reactor hydrodynamics, photon flux effects, typical reaction d ata (on benzene and trichloroethane), and rate constants. (C) 1998 Els evier Science Ltd. All rights reserved.