Gas-phase photocatalytic degradation of perchloroethylene on glass pellets immobilized with TiO{sub 2}
- Foo-Inn Inst. of Technology, Kaohsiung (Taiwan, Province of China). Dept. of Environmental Engineering
- National Sun Yet-Sen Univ., Kaohsiung (Taiwan, Province of China). Inst. of Environmental Engineering
The objective of this research was to study gas-phase photocatalytic degradation of perchloroethylene (PCE) under illumination of four 10-W near-ultraviolet (UV) light lamps. Experiments were performed in a photocatalytic reactor packed with Degussa P-25 TiO{sub 2}-coated glass pellets. Anatase TiO{sub 2} was applied as the photocatalyst in the investigation. The effects of reaction parameters including influent PCE concentrations (10 to 50 ppm), water vapor content (0 to 100 % relative humidity), oxygen concentrations (0.31 to 21%), reactor space times (0.55 to 1.83 seconds), and irradiated light intensity (0.4 to 1.0 mW/cm{sup 2}) were investigated in the study. Experimental results indicated that fast photocatalytic degradation of PCE took place in the presence of TiO2 illuminated with near-UV light. Experimental results also showed that the highest degradation rate and quantum efficiency of PCE were 0.523 m mol/secgm and 5.2 %, respectively. The highest conversion ratio of PCE of 99.8 % was achieved in the study. Greater conversation ratios of PCE were observed for longer reaction time. Increase in the reaction rates of PCE by increasing influent PCE and oxygen concentrations were presented. Higher reaction rates of PCE under stronger illumination light intensity were detected. The degradation rates of PCE were proportional to light intensity with the power order of 1.2. On the other hand, the inhibited degradation of PCE was observed in the presence of water vapor. Lower reaction rates of PCE were detected when water vapor was present in the reaction. A modified Langmuir-Hishelwood kinetic was applied to model photocatalytic degradation of PCE. Two different adsorption sites on irradiated TiO2{sub 2} surfaces for the adsorption of PCE and oxygen molecules respectively were assumed in the model. The assumption of water vapor competing with PCE for reactive sites was considered in the reaction.
- OSTI ID:
- 679326
- Report Number(s):
- CONF-980632-; TRN: IM9940%%146
- Resource Relation:
- Conference: 91. annual meeting and exhibition of the Air and Waste Management Association, San Diego, CA (United States), 14-18 Jun 1998; Other Information: PBD: 1998; Related Information: Is Part Of Proceedings of the 91. annual meeting and exhibition. Bridging international boundaries: Clean production for environmental stewardship; PB: [5000] p.
- Country of Publication:
- United States
- Language:
- English
Similar Records
Efficiency of clay-TiO2 nanocomposites on the photocatalytic eliminationof a model hydrophobic air pollutant
Rapid microwave hydrothermal synthesis of ZnGa{sub 2}O{sub 4} with high photocatalytic activity toward aromatic compounds in air and dyes in liquid water