Study On Preparation Of Modification Nano TiO₂ And Its Photocatalytic Degradation For Environmental Organic Pollutants

As a new photocatalyst, nano dioxide titanium is non-toxic, no secondary pollution and economical in the aspect of photocatalysis degradation organics, which is the developing direction of new environment protection technology. However, due to the wide band gap of nano dioxide titanium, only can UV-light be absorbed, which highly restrained the applied range of nano dioxide titanium in the field of depollution of environment, so, through modification technology to make nano dioxide titanium absorb visible light has been the important task in the field of photocatalysis. This program mainly studied the ion doping and surface sensitization modification technology and the application of modification photocatalysts in organic photocatalysis degradation.N-doped TiO2, N-Fe co-doped TiO2 with a redox treatment and CuPcTs sensitized nanocrystalline TiO2 photocatalyst (CuPcTs/TiO2) were prepared respectively and were characterized by SEM and XRD to analysis their surface topography and crystal form. Di-2-Ethyl Hexyl Phthalate (DEHP) and pentachloraphenol (PCP) were used as simulation pollutants to test the photocatalysis performance of the catalyst samples.The N single-doped titanium dioxide powder was prepared by hydrolysis-precipitation process with a series of different calcinations temperature. Through the analysis of characterization result and photocatalysis performance, the best calcinations temperature was set as 500 centigrade, the remove rate of DEHP by N-doped titanium dioxide reached to 84.33%. on the basis of confirming the optimum synthesization technology of N-doped titanium dioxide, we moved forward to synthesis the N-Fe co-doped titanium dioxide with a redox treatment. The co-doped photocatalysis was used to decompose pentachloraphenol, it was found, due to the synergistic effect and the change of ferrum crystal, the photocatalytic activity of N-Fe co-doped titanium dioxide with a redox treatment was enhanced obviously, the effect of photocatalysis was up to 86.8%.The CuPcTs sensitized TiO2 photocatalyst (CuPcTs/TiO2) was prepared by hydro-thermal synthesis process. Comparing to the unsensitized pure titanium dioxide, CuPcTs/TiO2 recombination nano photocatalyst had better photocatalytic activity, the remove rate for DEHP was increased obviously under visible light. It was found that the optimal concentration of catalyst was 0.4g/L, optimal pH level 5.0 and optimal irradiation time 50min, under these conditions, the removal rate of PCP reached up to 93.6%.