title: Photocatalytic oxidation of NOx over TiO2/HZSM-5 catalysts in the presence of water vapor: Effect of hydrophobicity of zeolites.
abstract: TiO(2) hybridized with HZSM-5 zeolites photocatalysts were prepared by a simple solid state dispersion method. The physicochemical properties of the catalysts were characterized by X-ray diffraction, UV-vis diffuse reflectance and FT-IR spectroscopy. The photocatalytic oxidation of NO(x) over TiO(2)/HZSM-5 having different Si/Al ratios was carried out under various levels of humidity and different pre-adsorption times in dark. The TiO(2)/HZSM-5 composite catalysts exhibited higher NO conversion and lower NO(2) formation than pure TiO(2). Pre-adsorption with water vapor and the high humidity during the photoreaction were harmful to the reactivity of TiO(2) hybridized with hydrophilic HZSM-5 zeolite. However, the photocatalytic reactivity of TiO(2) hybridized with hydrophobic zeolite varied little with increase in humidity. The results indicated that the high photocatalytic reactivity of TiO(2)/HZSM-5 catalysts is largely depended on the hydrophobicity of the zeolites.
authors.affiliation: The Key Lab of Pollution Control and Ecosystem Restoration in Industry Clusters, Ministry of Education, College of Environmental Science and Engineering, South China University of Technology, Guangzhou 510006, PR China.
authors.forename: Gaofei
authors.initials: G
authors.lastname: Guo
authors.forename: Yun
authors.initials: Y
authors.lastname: Hu
authors.forename: Shumei
authors.initials: S
authors.lastname: Jiang
authors.forename: Chaohai
authors.initials: C
authors.lastname: Wei
mesh_terms: D000327:Adsorption; D000393:Air Pollutants / Q000302:isolation & purification*; D002384:Catalysis; D052918:Environmental Restoration and Remediation / Q000295:instrumentation / Q000379:methods*; D004867:Equipment Design; D057927:Hydrophobic and Hydrophilic Interactions; D008855:Microscopy, Electron, Scanning; D009589:Nitrogen Oxides / Q000302:isolation & purification*; D010084:Oxidation-Reduction; D055668:Photochemical Processes; D016062:Porosity; D017550:Spectroscopy, Fourier Transform Infrared; D013499:Surface Properties; D014025:Titanium / Q000737:chemistry*; D014466:Ultraviolet Rays; D014961:X-Ray Diffraction; D017641:Zeolites / Q000737:chemistry*
chemical_list: D000393:Air Pollutants; D009589:Nitrogen Oxides; D017641:Zeolites; C009495:titanium dioxide; D014025:Titanium