Experimental Study Of Modified ZnO-TiO₂Photocatalytic Oxidation And Disinfection

A kind of photocatalyst ZnO-TiO2doped lanthanum, cerium,iron prepared bysol-gel; using X-ray diffraction, transmission electron microscopy, differential thermal-thermal gravimetric analysis, Raman spectrometer etc characterization; acid scarlet,reactive brilliant blue X-BR, reactive brilliant orange K-GN, reactive Violet K-3R,reactive Yellow XR, active bright red X-8B, reactive red KD-8B and a proprietaryChinese pharmaceutical wastewater photocatalytic degradation studies; choose threebetter photocatalysts for Escherichia coli and Staphylococcus aureus were sterilizedtrials.The results showed that the amount of TiO2doped zinc oxide is more appropriatefor less than5%, lanthanum, cerium, iron doping0.5%better in the crystal structure, theincorporation of rare earth elements in the catalyst specific surface area, porosityincreased significantly, increasing the chance of contact with the catalyst of organicmatter in water, increase the photocatalytic efficiency; catalyst calcination temperaturecalcination process, calcination time, heating rate optimal values were500℃,2h,5℃/min.The better three photocatalyst were0.3%lanthanum, mingled with3%ZnO ofZnO-TiO2(catalyst A), doped with0.3%Ce,3%ZnO of ZnO-TiO2(catalyst B), mixedwith0.3%Fe,2%of ZnO ZnO-TiO2(catalyst C). Catalyst A, B, C, respectively, forreactive brilliant blue X-BR, reactive brilliant red KD-8B, reactive yellow X-rbleaching highest rate, at96.4%,88.4%and85.1%, respectively. Catalyst forpharmaceutical wastewater degradation is not strong, the best one is catalyst A, thedecolorization rate and COD removal rate of58.5%,78.5%respectively.As the use of365nm UV light, catalysts A bactericidal effect is best of catalysts A, B, C,Staphylococcus aureus and Escherichia coli30min maximum bactericidal rate reached95.3%,95.6%.