title: Solar photodegradation of a textile azo dye using synthesized ZnO/Bentonite.
abstract: The present work is devoted to the synthesis of a new photocatalyst ZnO (7.5%)/Bentonite prepared by impregnation method and its successful application for the degradation of Solophenyl Red 3BL (SR 3BL) under solar light (∼660 W/m2). The X-ray diffraction (XRD) indicates mixed phases of the nanocomposite catalyst (ZnO/Bentonite), characterized by scanning electron microscopy, X-ray fluorescence and attenuated total reflection. The optical properties confirm the presence of the Wurtzite ZnO phase with an optical gap of 3.27 eV. The catalyst dose (0.25-1 gL-1), pH solution (2.5-11) and initial dye concentration (5-75 mg/L) are optimized. The optimal pH (∼6.7) is close to the natural environment. The photodegradation yield increases with decreasing the SR 3BL concentration. The equilibrium is reached within 160 min and the data are well fitted by the Langmuir-Hinshelwood model; the SR 3BL disappearance obeys to a first-order kinetic with an apparent rate constant of 10-2mn-1. The best yield of SR 3BL photodegradation (92%) is achieved for a concentration of 5 mg/L and a catalyst dose of 0.75 gL-1at free pH.
authors.affiliation: Laboratory of Storage and Valorization of Renewable Energies, USTHB, Algiers BP 32, Algeria E-mail: boutrabelkacem@gmail.com; boutra.belkacem@udes.dz; Unité de Développement des Equipements Solaires, UDES/Centre de Développement des Energies Renouvelables, CDER, Bou Ismail, W. Tipaza 42415, Algeria and Laboratory of Reaction Engineering, Faculty of Mechanical Engineering and Process Engineering USTHB, Algiers BP 32, Algeria.
authors.forename: B
authors.initials: B
authors.lastname: Boutra
authors.affiliation: Laboratory of Storage and Valorization of Renewable Energies, USTHB, Algiers BP 32, Algeria E-mail: boutrabelkacem@gmail.com; boutra.belkacem@udes.dz.
authors.forename: M
authors.initials: M
authors.lastname: Trari
mesh_terms: D000327:Adsorption; D001391:Azo Compounds / Q000528:radiation effects*; D001546:Bentonite / Q000737:chemistry*; D002384:Catalysis / Q000528:radiation effects; D004396:Coloring Agents / Q000528:radiation effects*; D006835:Hydrazones / Q000528:radiation effects; D006863:Hydrogen-Ion Concentration; D007700:Kinetics; D008855:Microscopy, Electron, Scanning; D053761:Nanocomposites; D010782:Photolysis / Q000528:radiation effects*; D013052:Spectrometry, X-Ray Emission; D013055:Spectrophotometry, Infrared; D013472:Sunlight; D013784:Textiles / Q000528:radiation effects*; D014961:X-Ray Diffraction; D015034:Zinc Oxide / Q000737:chemistry*
chemical_list: D001391:Azo Compounds; D004396:Coloring Agents; D006835:Hydrazones; C509104:Solophenyl red 3BL; D001546:Bentonite; D015034:Zinc Oxide