title: The use of oxyhalogen in photocatalytic reaction to remove o-chloroaniline in TiO2 dispersion.
abstract: Photodecay of o-chloroaniline (o-ClA) in various combinations of UV sources, TiO2, and oxyhalogens was investigated. To improve the conventional photocatalytic process by using UV/TiO2, the addition of oxyhalogens (ClO3(-), BrO3(-) and IO3(-)) into UV/TiO2 system was studied and the effect in such addition is very encouraging for all the selected additives. Oxyhalogens are capable of deferring the electron-hole recombination of TiO2 which significantly improved its catalytic performance. The presence of IO3(-) in UV/TiO2 resulted in the fastest o-ClA decay among three oxhalogens at the same dosage. The decay of o-ClA in UV/TiO2/oxyhalogen process is characterized by a two-stage pseudo-kinetics, where a faster initial decay was followed by a retardation state. A mathematics model was successfully established for the prediction of the two-stage decay of o-ClA in UV/TiO2/IO3(-) with any designed [IO3(-)] concentration.
authors.affiliation: Department of Civil and Structural Engineering, Research Centre for Environmental Technology and Management, The Hong Kong Polytechnic University, Hung Hom, Hong Kong.
authors.forename: W K
authors.initials: WK
authors.lastname: Choy
authors.forename: W
authors.initials: W
authors.lastname: Chu
mesh_terms: D000814:Aniline Compounds / Q000737:chemistry*; D002384:Catalysis; D006219:Halogens / Q000737:chemistry*; D007700:Kinetics; D008956:Models, Chemical; D010777:Photochemistry / Q000379:methods*; D014025:Titanium / Q000737:chemistry*; D014466:Ultraviolet Rays; D018508:Water Purification / Q000379:methods*
chemical_list: D000814:Aniline Compounds; D006219:Halogens; C009495:titanium dioxide; D014025:Titanium; C025257:2-chloroaniline