- Tuesday, August 25, 2009
- CdS-sensitized TiO2 in phenazopyridine photo-degradation: Catalyst efficiency, stability and feasibility assessment
- Published at:Finally Accepted, Journal Hazardous Materials, Elsevier, August 19, 2009
Journal of Hazardous Materials 173 (2010) 318–325Ahed H. Zyoud, Nidal Zaatar and Cheknane Ali, Iyad Saadeddin, DaeHoon park, Guy Campet, Hikmat S. Hilal*
Feasibility of using CdS-sensitized TiO2 catalyst systems was investigated in visible-light driven degradation of a medically active contaminant phenazopyridine, 1, in water. The TiO2/CdS systems showed high activity compared to un-sensitized TiO2 counterpart. The reaction kinetics were consistent with photodegradation processes encountered with other contaminants. The tendency of the sensitizer CdS to leach out hazardous Cd2+ ions was observed under photo-degradation conditions. To prevent leaching, different techniques were attempted such as annealing the TiO2/CdS system and supporting it onto solid sand supports. Unfortunately, complete prevention of Cd2+ ion leaching out was not possible by these methods under different experimental conditions. Therefore, unless complete prevention of such leaching out process is attainable, the use of CdS (and other hazardous synthetic sensitizers) should be avoided.
Ahed H. Zyoud, Nidal Zaatar and Cheknane Ali, Iyad Saadeddin, DaeHoon park, Guy Campet, Hikmat S. Hilal*