title: Sonophotocatalytic mineralization of Norflurazon in aqueous environment.
abstract: Norflurazon (4-chloro-5-(methylamino)-2-[3-(trifluoromethyl)phenyl]pyridazin-3(2H)-one; C12H9ClF3N3O) is an excellent weed controlling agent being practiced in the agricultural lands. The excessive addition or the undissolved Norflurazon (maximum solubility 28 mg/L at 25 °C) enters into the aquatic environment and causes the adverse effects associated with its high concentration. To avoid the perilous effects, visible light assisted photocatalysis set-up coupled with the 42 kHz ultrasound producing bath type sonicator is used to completely mineralize the Norflurazon. TiO2, ZnO and gold loaded zinc oxide nanocatalysts were utilized to study the mineralization of Norflurazon. Au-ZnO shows the greater efficiency for the sonophotocatalytic removal of Norflurazon among the various nanocatalysts employed to study the mineralization. The order of Norflurazon mineralization was sonophotocatalysis > sonocatalysis > photocatalysis. The additive effect was achieved for the sonophotocatalytic degradation. The high performance liquid chromatography (HPLC) and liquid chromatography-mass spectrometric (LCMS) analyses were employed to identify the various intermediates produced during the mineralization. The identification of four pseudo molecular ions and various intermediates using the LCMS analysis evidently suggests the sonophotocatalytic degradation was preceded in various decay pathways. A suitable mechanism has been proposed for the sonophotocatalytic mineralization of Norflurazon.
authors.affiliation: Advanced Ceramics and Nanotechnology Laboratory, Department of Materials Engineering, Faculty of Engineering, University of Concepcion, Concepcion 407-0409, Chile; Department of Chemistry, Periyar Maniammai University, Vallam, Thanjavur 613403, Tamil Nadu, India. Electronic address: sathish_panner2001@yahoo.com.
authors.forename: Panneerselvam
authors.initials: P
authors.lastname: Sathishkumar
authors.affiliation: Advanced Ceramics and Nanotechnology Laboratory, Department of Materials Engineering, Faculty of Engineering, University of Concepcion, Concepcion 407-0409, Chile. Electronic address: mangal@udec.cl.
authors.forename: Ramalinga Viswanathan
authors.initials: RV
authors.lastname: Mangalaraja
authors.affiliation: Faculty of Chemical Sciences, University of Concepcion, PO Box 160-C, Correo 3, Concepcion, Chile.
authors.forename: Oscar
authors.initials: O
authors.lastname: Rozas
authors.affiliation: Instrumental Analysis Department, Faculty of Pharmacy, University of Concepción, PO Box 160-C, Correo 3, Concepción, Chile.
authors.forename: Carola
authors.initials: C
authors.lastname: Vergara
authors.affiliation: Faculty of Chemical Sciences, University of Concepcion, PO Box 160-C, Correo 3, Concepcion, Chile.
authors.forename: Héctor D
authors.initials: HD
authors.lastname: Mansilla
authors.affiliation: Universidad Autónoma de Nuevo León, Facultad de Ciencias Físico-Matemáticas, Av. Universidad, Cd. Universitaria, San Nicolás de los Garza, N.L., Mexico; Universidad Autónoma de Nuevo León, Centro de Investigación e Innovación en Desarrollo de Ingeniería y Tecnología, Avenida Alianza 101 Sur PIIT Monterrey, Apodaca, N.L. 66600, Mexico.
authors.forename: M A
authors.initials: MA
authors.lastname: Gracia-Pinilla
authors.affiliation: Nanomaterials and Solar Energy Conversion Lab, Department of Chemistry, National Institute of Technology, Trichy 620 015, India.
authors.forename: Sambandam
authors.initials: S
authors.lastname: Anandan
mesh_terms: D002384:Catalysis; D002851:Chromatography, High Pressure Liquid; D006046:Gold / Q000737:chemistry; D007700:Kinetics; D008027:Light; D053758:Nanoparticles / Q000737:chemistry; D011724:Pyridazines / Q000032:analysis* / Q000737:chemistry / Q000528:radiation effects; D021241:Spectrometry, Mass, Electrospray Ionization; D013499:Surface Properties; D014025:Titanium / Q000737:chemistry; D000069453:Ultrasonic Waves; D014874:Water Pollutants, Chemical / Q000032:analysis* / Q000737:chemistry / Q000528:radiation effects; D015034:Zinc Oxide / Q000737:chemistry
chemical_list: D011724:Pyridazines; D014874:Water Pollutants, Chemical; C009495:titanium dioxide; D006046:Gold; D014025:Titanium; C008677:norflurazone; D015034:Zinc Oxide
keywords: HPLC and LC-MS analyses; Mineralization; Norflurazon; Sonophotocatalysis; Visible light