2006 Fiscal Year Final Research Report Summary
Development of a combined biological and photocatalytic treatment apparatus for the continuous degradation of water pollutants
Grant-in-Aid for Scientific Research (C)
|Allocation Type||Single-year Grants |
Environmental technology/Environmental materials
|Research Institution||University of Toyama |
HASEGAWA Kiyoshi University of Toyama, Faculty of Engineering, Professor -> 富山大学, 工学部, 名誉教授 (20019186)
KUMAZAWA Hidehiro University of Toyama, Faculty of Engineering, Professor, 工学部, 教授 (70023281)
KAGAYA Shigohiro University of Toyama, Faculty of Engineering, Assistant Professor, 工学部, 助教授 (50272894)
|Project Period (FY)
2005 – 2006
|Keywords||Biological-photocatalytic treatment / Reuse of titanium dioxide / Phenol / Wastewater treatment / Pilot scale apparatus / Continuous flow operation / Utilization of sunlight / Optimization of operation|
A solar pilot scale biological-photocatalytic treatment apparatus integrated with TiO_2 separation (B-P-S) was developed. The optimum operation conditions were examined to increase the degradation of the concentrated phenol in an electrolyte-containing wastewater. A visible light-responsive Fe-doped TiO_2 photocatalyst and the combined photocatalyst of P25 TiO_2 and Fe(ClO_4)_3 were prepared and they were applied to the degradation of phenol. A pilot scale photocatalysis-TiO_2 separation apparatus (P-S) were also studied.
1. A solar B-P-S apparatus and application to the degradation of concentrated phenol
The solar B-P-S apparatus was developed. Concentrated phenol (200 ppm) in the electrolyte-containing wastewater was continuously mineralized. The mineralization of chlorophenols was also examined. Flow (biotreatment)-high speed circulation (photocatalysis)-flow (TiO_2 separation) operation was optimum. Continuous operation was attained without stopping the inflow of the wastewater and t
he outflow of the treated water, and the treated water (phenol : 0.6 and TOC : 6.5 ppm) was discharged at the flow rate of 15 mL/min.
2. Degradation of diluted phenol using visible light-responsive photocatalysts
(1) A visible light-responsive Fe-doped TiO_2 photocatalyst and (2) a combined photocatalyst of P25 TiO_2 and Fe(ClO_4)_3 were prepared and they were applied to the degradation of diluted phenol. In (1), the degradation depended on the Fe content and the Fe-doped TiO_2 was responsive to the visible light as well as the elevated activity toward UV light. In (2), the degradation rate was higher than the sum of the rates for the separately used single photocatalyst. The reason was discussed based on the catalytic cycle of Fe(III)/Fe(II).
3. AP-S apparatus and application to the degradation of phenol in wastewater
The continuous flow P-S apparatus was developed. The photocatalytic degradation of phenol (20 ppm) in the electrolyte-containing wastewater was examined with the combined photocatalyst (pH 3). At the flow rate of 400 mL/min, the degradation of phenol was enhanced more than that in distilled water while depressing the coagulation of TiO_2 by the electrolytes. The reason was discussed Less
Research Products (8 results)