title: Photocatalytic degradation of isoproturon herbicide over TiO2/Al-MCM-41 composite systems using solar light.
abstract: The present investigation covers immobilization of TiO2 using a simple solid state dispersion technique over mesoporous Al-MCM-41 support for the treatment of isoproturon herbicide. Catalysts are characterized by XRD, X-ray photo electron spectroscopy (XPS), surface area, UV-Vis diffused reflectance spectra (DRS), SEM and TEM. A detailed photocatalytic degradation study of isoproturon under solar light in aqueous suspensions is reported. The 10 wt% TiO2/Al-MCM-41 composite system found to be optimum with high degradation activity. The reaction follows pseudo-first order kinetics. The parameters like TiO2 loading over Al-MCM-41, amount of catalyst, concentration of substrate, pH effect, durability of the catalyst, activity comparison of TiO2 and Al-MCM-41 supported system are studied. The mineralization of isoproturon is monitored by TOC. Based on the degradation products detected through LC-MS, a plausible degradation mechanism is proposed. The data indicates that TiO2/Al-MCM-41 composite system is an effective photocatalyst for treatment of isoproturon in contaminated water.
authors.affiliation: Inorganic and Physical Chemistry Division, Indian Institute of Chemical Technology, Hyderabad 500 607, India.
authors.forename: M V
authors.initials: MV
authors.lastname: Phanikrishna Sharma
authors.forename: V
authors.initials: V
authors.lastname: Durga Kumari
authors.forename: M
authors.initials: M
authors.lastname: Subrahmanyam
mesh_terms: D002384:Catalysis / Q000528:radiation effects; D002853:Chromatography, Liquid; D006540:Herbicides / Q000737:chemistry* / Q000528:radiation effects; D006863:Hydrogen-Ion Concentration; D013058:Mass Spectrometry; D008903:Minerals / Q000737:chemistry; D010671:Phenylurea Compounds / Q000737:chemistry* / Q000528:radiation effects; D010777:Photochemistry; D016062:Porosity; D012822:Silicon Dioxide / Q000737:chemistry*; D013472:Sunlight; D014025:Titanium / Q000737:chemistry* / Q000528:radiation effects; D014874:Water Pollutants, Chemical / Q000737:chemistry* / Q000528:radiation effects; D014961:X-Ray Diffraction
chemical_list: D006540:Herbicides; C509968:MCM-41; D008903:Minerals; D010671:Phenylurea Compounds; D014874:Water Pollutants, Chemical; C009495:titanium dioxide; C028904:isoproturon; D012822:Silicon Dioxide; D014025:Titanium