title: Photocatalytic oxidation of selected gas-phase VOCs using UV light, TiO2,and TiO2/Pd.
abstract: Heterogeneous photocatalytic oxidation systems using titanium dioxide (TiO2) have been extensively studied for the removal of several volatile organic compounds (VOCs). The addition of noble metals such as palladium on TiO2may improve photocatalytic activity by increasing charge separation efficiency. In this work, palladium was impregnated on TiO2and the efficiency of the new catalyst was tested and compared with that of pure TiO2. Pd was impregnated on TiO2by the reduction method, using NaBH4, and was characterized by XRD, XPS, UV-Vis, and H2chemisorption. The photocatalytic tests were performed in an annular coated-wall reactor using octane, isooctane, n-hexane, and cyclohexane at inlet concentrations varying from 100 to 120 ppmv. Compared with pure TiO2film, the photocatalytic activity of TiO2impregnated with 1 wt% of palladium was improved. All the aforementioned analytical techniques confirmed the presence of Pd incorporated into the structure of TiO2,and the conversion rates were studied in a broad range of residence times, yielding up to 90 % or higher rates in 40 s of residence time, thus underscoring the relevant contribution of the technology.
authors.affiliation: Faculty of Chemical Engineering, University of Campinas-UNICAMP, Av. Albert Einstein, 500, Campinas, 13083-852, SP, Brazil. taniafujimoto@gmail.com.
authors.forename: Tânia M
authors.initials: TM
authors.lastname: Fujimoto
authors.affiliation: Faculty of Chemical Engineering, University of Campinas-UNICAMP, Av. Albert Einstein, 500, Campinas, 13083-852, SP, Brazil.
authors.forename: Milena
authors.initials: M
authors.lastname: Ponczek
authors.affiliation: Faculty of Chemical Engineering, University of Campinas-UNICAMP, Av. Albert Einstein, 500, Campinas, 13083-852, SP, Brazil.
authors.forename: Ursula L
authors.initials: UL
authors.lastname: Rochetto
authors.affiliation: "Gleb Wataghin" Institute of Physics-IFGW, University of Campinas-UNICAMP, Av. Albert Einstein, 500, Campinas, 13083-852, SP, Brazil.
authors.forename: Richard
authors.initials: R
authors.lastname: Landers
authors.affiliation: Faculty of Chemical Engineering, University of Campinas-UNICAMP, Av. Albert Einstein, 500, Campinas, 13083-852, SP, Brazil.
authors.forename: Edson
authors.initials: E
authors.lastname: Tomaz
mesh_terms: D000327:Adsorption; D000393:Air Pollutants / Q000302:isolation & purification*; D002384:Catalysis; D006586:Hexanes / Q000302:isolation & purification; D009795:Octanes / Q000302:isolation & purification; D010084:Oxidation-Reduction; D010165:Palladium / Q000737:chemistry*; D055668:Photochemical Processes; D014025:Titanium / Q000737:chemistry*; D014466:Ultraviolet Rays; D014961:X-Ray Diffraction
chemical_list: D000393:Air Pollutants; D006586:Hexanes; D009795:Octanes; C009495:titanium dioxide; C026385:n-hexane; D010165:Palladium; D014025:Titanium; C026728:octane
keywords: Gas phase; Heterogeneous photocatalysis; Pd; TiO2; UV; Volatile organic compounds