Visible Light Induced Photocatalytic Degradation Of 1,2,4-triglorobenzene By Co₃O₄ Particles

With the acceleration of industrialization, water pollution is more and more serious.The United Nations World Water Assessment Report of BBS fourth world water provided that there are around millions of tons of garbage and sewage poured into rivers, lakes and streams and other water pollutants every day. Chlorobenzene compounds as an important class of pollutants, its processing method of research by the wide attention of scholars both at home and abroad. Among them, the semiconductor photocatalytic oxidation technology has become the hot research spot.Co3O4 semiconductor forbidden band gap is 2.1 e V, that it is a good response to visible light photocatalytic materials, and 1,2,4-trichlorobenzene is a typical kind of compounds of chlorobenzene compounds, this paper adopts the Co3O4 semiconductor in visible light photocatalytic degradation of 1,2,4-trichlorobenzene in research.Mainly for the following research:1. Visible light response of light catalyst was prepared by sol-gel method,using X-ray diffraction, scanning electron microscopy(sem), uv-vis diffuse reflection spectra of catalyst characterization and structure analysis.2. Studied in different dosage of catalyst, reaction of the substrate concentration,initial solution p H value, reaction temperature and light intensity of Co3O4 on1,2,4-trichlorobenzene visible light catalytic degradation affects the results of the analysis and discussion.The results found that the catalyst in the 0.5 g(per unit volume quality is 0.125 g/L) when the photocatalytic efficiency is the best; Reaction substrates in 7.5 mg/L when the photocatalytic efficiency is the best, with the increase of the photocatalytic reaction substrate concentration efficiency decreases; The initial solution p H value neutral near the end of the degradation efficiency is low, the increase of H+or OH-all in the solution favorable light catalytic degradation; In the temperature range of experiment, with the increase of temperature, photocatalytic degradation efficiency increased gradually at 30 ? have best effect; With the increase of light intensity, photocatalytic efficiency increased gradually, the xenon lamp degradation have the best effect when maximum power is 350 W.3. The effects of other factors on photocatalytic degradation were studied. Under the influence of 50 mg/L of humic acid, photocatalytic degradation efficiency decreased by 19.2%; Tendency in 2.5mmol/L under the influence of H2O2,photocatalytic degradation rate increased by 5.7%; With the cationic surfactant dodecyl trimethyl ammonium bromide and Co3O4 combination photocatalytic degradation efficiency increased by 4.2%.4. Finally, Co3O4 photocatalytic degradation of 1,2,4-trichlorobenzene under the influence of various reaction conditions and impurities of the reaction rate of dynamics research, found that it is basically accord with first order kinetics equation and have the good linear correlation, according to the reaction rate constant,determine its rate relations under the influence of different reaction conditions and impurities.