Liquid-phase non-thermal plasma-prepared N-doped TiO(2) for azo dye degradation with the catalyst separation system by ceramic membranes.
This study strived to improve the photocatalytic activity by using liquid-phase non-thermal plasma (LPNTP) technology for preparing N-doping TiO(2) as well as to separate/recover the N-dope TiO(2) particles by using ceramic ultrafiltration membrane process. The yellow color N-doped TiO(2) photocatalysts, obtained through the LPNTP process, were characterized with UV-Vis spectroscopy, X-ray diffraction (XRD), and electron spectroscopy for chemical analysis (ESCA). The UV-Vis spectrum of N-doped TiO(2) showed that the absorption band was shifted to 439 nm and the band gap was reduced to 2.82 eV. The structure analysis of XRD spectra showed that the peak positions and the crystal structure remained unchanged as anatase after plasma-treating at 13.5 W for 40 min. The photocatalytic activity of N-doped TiO(2) was evaluated by azo dyes under visible light, and 63% of them was degraded after 16 hours in a continuous-flow photocatalytic system. For membrane separation/recover system, the recovery efficiency reached 99.5% after the ultrafiltration had been carried out for 90 min, and the result indicated that the photocatalyst was able to be separated/recovered completely.
Cheng
Hsu-Hui
HH
Institute of Environment Engineering and Management, National Taipei University of Technology, Taipei 10643, Chinese Taiwan. dyuchina@hotmail.com
Chen
Shiao-Shing
SS
Cheng
Yi-Wen
YW
Tseng
Wei-Lun
WL
Wang
Yi-Hui
YH
D001391:Azo Compounds / Q000737:chemistry*; D002384:Catalysis; D002516:Ceramics; D004396:Coloring Agents / Q000737:chemistry*; D009584:Nitrogen / Q000737:chemistry*; D010782:Photolysis; D013997:Time Factors; D014025:Titanium / Q000737:chemistry*; D014872:Water Movements; D014874:Water Pollutants, Chemical / Q000737:chemistry*; D018508:Water Purification / Q000295:instrumentation / Q000379:methods
D001391:Azo Compounds; D004396:Coloring Agents; D014874:Water Pollutants, Chemical; C009495:titanium dioxide; D014025:Titanium; D009584:Nitrogen