Treating dye wastewater by TiO_2 coated on coal cinder
LIU Jian-hua 1,2, WANG Hai-jun 2 1 Key Laboratory of Yangtze River Water Environment, Ministry of Education, Yibin University, Sichuan 644000, P. R. China 2 Department of Chemical and Material Engineering, Jiangnan University, Jiangsu 214122, P. R. China
We investigated the photocatalytic degradation of dye wastewater by using titanium dioxide (TiO2) coated on a coal cinder. The coal cinder was used as the carrier, with a thin film of TiO2 coated on it by using the sol-gel method. Using the Congo red as the model pollutant for dye wastewater, we studied the decolorization efficiency, and effects of TiO2 film thickness and roasting temperature on the efficiency. We also evaluated the recycling and regeneration of the immobilized TiO2 (TiO2/cinder). Results show that the decolorization rate of Congo red solution was more than 98% after 2 h treatment when we used TiO2/cinder calcined at 500 °C for 2 h and coated four times as the photocatalyst. At the same time, the TiO2/cinder remained high catalytic activity after being reused and regenerated for many times.