Supported Modified Nano Tio <sub> 2 </ Sub> Photocatalytic Degradation Of Dye Wastewater Pilot Study

Nanosized T1O2 has the properties of high superficial area, high density, superficial crystal lattice lacuna and high superficial area energy, and it has excellent chemical stability, innocuity, high catalyzed activity, high reaction speed, low option to organics degradation and fully mineraling organics to CO2 & H2O. Doped some metallic ion or alter its property on surface when treating wastewater and purifying air can effectively hinder charge recovery in the course of transferring and improve its catalyst activity. In order to make full use of sunlight, it is necessary to dope some semiconductor photocatalyst to improve catalyst activity and expand its responding spectrum area. The study on using sunlight to deal with pollutants is very important for protecting environment, maintaining zoology balance and achieving sustained development.Basing on the present situation of dye water pollution, the paper studies experiments conditions on immobilized nanosized T1Q2 photocatalyst and doped immobilized nanosized TiO2 photocatalyst degrading common dye wastewater and working mechanism.The experiments use cokes as the carriers, Na2SiO3 as adhensive. The degradation ability of immobilized nanosized TiO2 photocatalyst, Fe or Cu doped immobilized nanosized TiQ2 photocatalysts are studied. Using ultra-light and sunlight as lamp-house respectively, degradation results of different immobilized nanosized T1Q2 photocatalyst are studied under the same experimental conditions. Meanwhile, kinds of photocatalysts degradation mechanisms are discussed.At the same time, in order to studied the factor, such as adhensive concentration, doped metal quality, calcining temperature, calcining time, orthogonal tests of L9(33) L9(34) have been done. The other factors, such as coated quality, coated times and sunlight density are studied as well.The experimental results of the study are as follows:(1) Immobilized nanosized TiO2 photocatalyst: the optimal TiO2 weight percent of coated liquid is 18%; the optimal conditions by orthogonal test are: calcining temperature is 400癈, adhensive aqueous weight percent is 20%, calcining time is 3h, and the highest degradation rate to dye wastewater is 80.88%. The factor importance order is: calcining temperature> Na2SiO3 weight percent > calcining time. However, Immobilized nanosized TiO2 photocatalyst powder flaked away heavily, and its reuse is poor. The degradation rate of Methylene blue wastewater is in proportion to light intensity I, the degradation rate is 89.86% at the highest sunlight intensity 4.585x100uw/cm2.(2) Doped immobilized nanosized TiO2 photocatalyst: when using ultra-light as lamp-house, The factor importance order by the doped Fe orthogonal test is: calcining time > calcining temperature> Na2SiO3 weight percent > doped Fe quantity; when using sunlight as lamp-house, The factor importance order by the doped Fe orthogonal test is: calcining time > doped Fe quantity > Na2SiO3 weight percent > calcining temperature; the optimal conditions by doped Fe orthogonal tests are: calcining temperature is 400癈, adhensive aqueous weight percent is 20 %, calcining time is 3h. The degradation rates of Fe2O3 doped immobilized photocatalyst are obviously higher than that of Fe(OH)3 doped immobilized photocatalyst When Fe doped weight percent is 2%, the highest degradation rate is obtained. Moreover, TiO2 flaked away little, and its reuse was good. As for the Cu doped immobilized nanosized TiO2 photocatalyst, the degradation rates of CuO doped immobilized photocatalyst are higher than that of Cu(OH)2 doped immobilized photocatalyst. When Cu doped weight percent was 2%, the highest degradation rate is obtained. The degradation rates of Fe doped immobilized photocatalyst are obviously higher than that of Cu doped immobilized photocatalyst.