Performance Of Micron-sized TIO2/AC Catalysts In A Photocatalytic-membrane Separation Coupled Reactor

The properties of the supported micro TiO₂/AC catalyst prepared by sol-gel method was characterized by XRD,SEM,FT-IR and particle size analysis,and the photocatalytic degradation performance,the suspension characteristics of TiO₂/AC and the influence on membrane flux in the photocatalytic-membrane separation coupling reaction were studied through the degradation of acid red B wastewater.The results showed that photocatalytic degradation performance of micro TiO₂/AC catalyst firstly increased,then decreased with the increasing of the catalyst dosage and the acid red B wastewater initial concentration,the appropriate catalyst dosage and acid red B wastewater initial concentration were 0.7 g/L and 18 mg/L respectively.The photocatalytic degradation performance and suspension concentration of TiO₂/AC firstly increased,then decreased with the calcination temperature of TiO₂/AC increasing from 300? to 500?,at the 400? optimum calcination temperature,the TiO₂ supported on the activated carbon was mainly anatase,and its distribution was relatively homogenous,TiO₂ and carrier activated carbon was combined by Ti-O-C bond.The photocatalytic degradation performance and suspension concentration of micro TiO₂/AC catalyst firstly increased,then decreased with the decreasing size of activated carbon carrier from 20.308 ?m to 1.913 ?m.And the photocatalytic degradation performance and suspension concentration of micro TiO₂/AC catalyst also firstly increased,then decreased with the decreasing size of catalyst from 38.137?m to 3.747?m.The optimum size of carrier and catalyst were 2.126?m and 10.272 ?m respectively.The photocatalytic degradation performance and suspension concentration of TiO₂/AC catalyst which the carrier made by coconut shell activated carbon was higher than that made by lignite activated carbon.The photocatalytic degradation performance of micron TiO₂/AC catalyst was higher than that of commercial TiO₂,while the suspension concentration was lower than that of commercial TiO₂.The membrane flux firstly increased,and then decreased with the increasing of calcination temperature,decreasing size of activated carbon carrier and catalyst respectively,the optimum calcination temperature,size of activated carbon carrier and catalyst was 400?,2.126?m and 10.272?m respectively.The effects of micro TiO₂/AC catalyst which the carrier made by coconut shell activated carbon was lower than that made by lignite activated carbon on membrane flux.Increasing the aeration rate at the conditions of bottom aeration and backwashing were beneficial to increase the membrane flux,and the optimum aeration rate was 0.042 m3/h.The effect of micro TiO₂/AC catalyst on membrane flux was lower than that of commercial TiO₂.