| With palygorskite as the carrier, tetrabutyl titanate as precursor, TiO2 composite catalysts of palygorskite was prepared by sol-gel method in the study.In the other hand ,the effecction of change on catalyst was also studied through doped SnO2. The catalyst performance and structure of catalyst was study by XRD, TEM, and other analytical tools.The wastewater of P-dihydroxybenzene was treated by preparation of catalyst under the UV light sources and sunlight stimulsted by xenon lamp condition, come to the following conclusions(1) Compositing catalyst, which was made by calcine at 500℃for 3 hours and TiO2 and palygorskite theoretical mass ratio is 35%, Sn and Ti theoretical mol ratio is 6%, has the best photocatalytic effect.Through characterized by XRD, TEM, we can konw that TiO2 evenly even spread on the surface of palygorskite like nanocomposites.(2) Initial concentration is 50mg/L ,the dosage is 1.0g/L, in the lighe of xenon lamp 500w, in the water of p-dihydroxybenzene simulate waste water , after 2 hours, removal rate can be 67.7 %. Then , in the same situation the removal rate of pure TiO2 only 36%,at the same time compositing catalyst can get excellent absorbend ability.So we can know that, compositing catalyst's photocatalystic ability is better than the pure TiO2, doping Sn can increase the range of the absorption wavelength,arose the red shift occoured.(3) The palygorskite is prepared by experimental methods.The removal rate of the palygorskite loaded by TiO2/SnO2 composite photocatalyst descends six percents after resued threetimes still with high photocatalystic,so it is can be concluded that this composite material is worthy to be recycled.(4) Using L-H Dynamic model fitting with the Photocatalytic experimental results.It is found that photocatalytic oxidation-reduction under this experimental condition agrees with first order kinetics equation,and the adsorption composite photocatalyst is conformed to pseudo second order kinetics equation.
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