Preparation and Photocatalytic Performance of TiO_2-coated Natural Zeolite in Degradation of Papermaking Wastewater

Using Ti(OC4H9)4 and C2H5OH as reaction raw materials, the photocatalyst of TiO2-coated natural zeolite was prepared by sol-gel method. The experimental techniques of XRD and SEM were used to characterize the prepared TiO2-coated photocatalyst. The influences of components of sol-gel system, calcination temperature and time, amount of catalyst, radiation time and pH value on the photocatalytic degradation of papermaking wastewater on the TiO2 coated natural zeolite were studied. The optimal experimental conditions were obtained: the volume ratios of C2H5OH to TiO(C4H9)4 4.0, CH3COOH to TiO(C4H9)4 0.1, H2O to TiO(C4H9)4 0.15 and HNO3 to TiO(C4H9)4 0.1, calcination temperature 300℃, calcination time 4.0 h, amount of catalyst 50 g/L, pH value of papermaking wastewater 4.0, and radiation time 8.0 h, the COD removal rate of papermaking wastewater reached 81.93% under the conditions. The experimental results show that TiO2-coated natural zeolite has a good photocatalytic activity to degrade papermaking wastewater.