Study On Preparation Of TiO₂ Composite Photocatalyst Attached To Celite & Bentonite Shaped Vector

Photo-catalysis oxidation technology develops rapidly in recent years.It has been used widely to treat wastewater and waste gas and good effect achieved. TiO2 is commonly used in photo catalytic oxidation process as an efficient photocatalysis.it can irradiate by weak intensity UV effectively and keep good stability in wide pH range and nontoxic.But its practical application is limited by being easy to inactivate, condense and hard to separate.In this paper shaped vector is tried to be prepared with celite, bentonite and active carbon powder by sodium silicate. Supported nano- TiO2 is prepared with metatianic acid as the materials by microwave on the vector surface and its photocatalysis properties.First of all,the forming method of catalyst carrier was studied in this paper and such as the selection of binders,the optimum proportion of raw materials, optimum amount of binder,harding temperature, harding time and activated carbon addition were studied too to determine optimum conditions,that was,sodium silicate was the best binder among the experimental samples, the optimal proportioning of celite,bentonite and active carbon powder was 4:3:2,sodium silicate and raw material was 1:1.It was suitable for the vector to hard at 300 ℃ for 2h.Next step, supported nano-TiO2 was prepared with the carrier and the degradation rate of methyl orange was analysised.Several factors were considered which would affect the loading condition and the optimum conditions were as below:suitable precursor concentration was 20g/L(content of TiO2),hydrolytic pH was 2.5,hydrolytic microwave power was 360W, microwave heating time was 15 mins, calcining temperature was 550℃ and calcining time was 2h.At last, the treatment effect of methyl orange solution was studied by using the composite photocatalyst which was prepared under the optimum conditions.The optimum photocatalytic oxidation reaction conditions were as below:initial concentration of methyl orange solution was 10mg/L, initial pH of reaction solution was close to 7, UV light intensity was 16W, UV light time was 2h.The optimum content of additional oxidant H2O2 was 0.6mmol/100ml.