PHOTOCATALYTIC DEGRADATION OF ORGANIC CONTAMINANTS BY CLAY- SUPPORTED NITROGEN-DOPED TIO2 NANOPARTICLES
Jihad Mohammed Kharouf, Mohammed
An Najah National University
Responding to the strong demands on new optimum photocatalyst, to decompose organic pollutants from the contaminated waste water. Titania is very effective as a photocatalyst. To achieve maximum absorption of sun light, doping was used to lowering the band gap energy. supporting on the clay successfully enhance the catalytic properties in addition to minimizing the effort of catalyst recovery. The photocatalytic activity of variety of catalysts has been studied utilizing with varying synthesis circumstances (annealing temperature, cover gas, etc.) and compositions (rutile, anatase) supported and unsupported on the clay surface. Two doping methods were made for comparison. The X-ray diffraction methods and scanning electron microscope and another elemental analysis were used to identify the catalyst states. There are no inter-layer intercalation titanium dioxide inside the clay, according to solid state studies. Another thing to note is that when the annealing temperature rises, the anatase begins to change to rutile form. Solid catalysts were used in order to photo-depredate the phenazopyridine contaminated water. Rutile and anatase titanium dioxide (naked and clay supported) types were invested as photocatalysts. Nitrogen doping using urea as a source of nitrogen effectively lowers the band gap energy, which inhibits the photocatalytic activity. On rutile, doping increases the catalytic properties and has no observed effect on band gap energy. The TiO2 (Rutile)/Clay supported catalyst outperforms the other catalysts and was successful in phenazopyridine photodegradation under simulated solar light. In addition, the ideal conditions were stated (pH, Temperature, quantities effect). Studying catalyst recovery where made for TiO2(Rutile)/Clay after four times, the efficiency of the recovered solid catalyst has not any noticeable loss. The full degradation was confirmed using TOC and HPLC which can be achieved under simulated sun light after 3 hours under the reaction conditions. As a result, supporting titania on the clay surface enhances the catalytic properties, recovery of the catalyst by simple decantation. And the doping affect differently according to the catalyst type and doping method.
Photocatalytic , Titanium dioxide , Doping, XRD, SEM