title: Mechanistic analysis on the influence of humidity on photocatalytic decomposition of gas-phase chlorobenzene.
abstract: The influence of humidity on the decomposition of gas phase chlorobenzene (CB) was studied in a batch photocatalytic reactor using TiO(2) (anatase). Increasing relative humidity (>7% at 25 degrees C and 1atm) resulted in an increasingly detrimental effect on the adsorption and photocatalytic decomposition rate of CB. Mechanistic analysis indicates that the relative hydrophilic/hydrophobic nature of a given chemical should dictate adsorption onto or penetration through water to the TiO(2) surface. It is suggested that multiple layers of water molecules are formed at the TiO(2) interface with air, even at low relative humidities. The multiple-layered film of water retards/prevents CB from reaching the reactive TiO(2) surface or contacting radical species in the boundary layer.
authors.affiliation: Department of Chemical Engineering, University of Waterloo, 200 University Avenue West, Waterloo, Ont., Canada N2L 3G1.
authors.forename: Lianfeng
authors.initials: L
authors.lastname: Zhang
authors.forename: William A
authors.initials: WA
authors.lastname: Anderson
authors.forename: Steven
authors.initials: S
authors.lastname: Sawell
authors.forename: Carol
authors.initials: C
authors.lastname: Moralejo
mesh_terms: D000327:Adsorption; D002722:Chlorobenzenes / Q000737:chemistry*; D004785:Environmental Pollutants; D005740:Gases / Q000737:chemistry*; D006813:Humidity; D010777:Photochemistry; D014025:Titanium / Q000737:chemistry
chemical_list: D002722:Chlorobenzenes; D004785:Environmental Pollutants; D005740:Gases; C009495:titanium dioxide; D014025:Titanium; C031294:chlorobenzene