title: CdS-sensitized TiO2 in phenazopyridine photo-degradation: catalyst efficiency, stability and feasibility assessment.
abstract: Mineralization of phenazopyridine, 1, in water, under solar-simulator radiation was efficiently achieved using nanoparticle CdS-sensitized rutile TiO(2), TiO(2)/CdS, 2, as photo-catalysts. Despite that, 2 showed two main drawbacks. Firstly, the system was difficult to recover by simple filtration, and demanded centrifugation. Secondly, the sensitizer CdS showed relatively high tendency to leach out hazardous Cd(2+) ions under photo-degradation reaction conditions. In an attempt to solve out such difficulties, 2 was supported onto sand surface. The sand/TiO(2)/CdS system, 3, was easier to recover but showed slightly lower catalytic activity compared to 2. On the other hand, the support failed to prevent leaching of Cd(2+). This indicates limited future applicability of CdS-sensitized TiO(2) photo-catalyst systems, in solar-based water purification strategies, unless leaching out tendency is completely prevented.
authors.affiliation: Department of Chemistry, An-Najah N. University, PO Box 7, Nablus, West Bank, Palestine.
authors.forename: Ahed H
authors.initials: AH
authors.lastname: Zyoud
authors.forename: Nidal
authors.initials: N
authors.lastname: Zaatar
authors.forename: Iyad
authors.initials: I
authors.lastname: Saadeddin
authors.forename: Cheknane
authors.initials: C
authors.lastname: Ali
authors.forename: DaeHoon
authors.initials: D
authors.lastname: Park
authors.forename: Guy
authors.initials: G
authors.lastname: Campet
authors.forename: Hikmat S
authors.initials: HS
authors.lastname: Hilal
mesh_terms: D019187:Cadmium Compounds / Q000737:chemistry*; D002384:Catalysis; D005240:Feasibility Studies; D006863:Hydrogen-Ion Concentration; D007700:Kinetics; D049449:Luminescence; D008506:Medical Waste / Q000032:analysis; D008855:Microscopy, Electron, Scanning; D010621:Phenazopyridine / Q000737:chemistry*; D010777:Photochemistry; D013056:Spectrophotometry, Ultraviolet; D013440:Sulfides / Q000737:chemistry*; D014025:Titanium / Q000737:chemistry*; D014961:X-Ray Diffraction
chemical_list: D019187:Cadmium Compounds; D008506:Medical Waste; D013440:Sulfides; C034939:cadmium sulfide; C009495:titanium dioxide; D014025:Titanium; D010621:Phenazopyridine