Preparation And Characterization Of Heteropoly Acid/Polyaniline/Semiconductor Composite Catalyst As Well As Performance Study

This thesis the main use TiO₂nanoparticles surface coated polyaniline film by usingchemical oxidation with （NH₄）₂S₂O₈as an oxidant, and then successfully prepared threenew-type composite of photocatalyst through the electrostatic self-assembly method（PMoV₁/PANI/TiO₂、PMoV₂/PANI/TiO₂and PMoV₃/PANI/TiO₂）. The characterized ofphotocatalyst use of N₂adsorption-desorption, FT-IR, XRD, UV-Vis, SEM and TG-DTGtechniques. In addition, using methylene blue （MB） and gentian violet （GV） as modelcompounds, studied amount of three types catalyst （PMoV₁/PANI/TiO₂、PMoV₂/PANI/TiO₂and PMoV₃/PANI/TiO₂）, the initial pH value and concentration of solution influence on thedegradation rate of methylene blue and gentian violet under condition of UV irradiation andsunlight, as well as degradation kinetics from the photocatalytic degradation of methyleneblue and gentian violet. The results indicates that under UV irradiation, initial concentrationof10mg/L, the amount of catalyst0.01g, initial pH value of5is the optimum conditionswith a high catalytic activity for degradation of methylene blue, the degradation rate canachieved92.50%、94.21%、97.10%after200min. Under the sunlight, degradation rate ofthree kinds of catalyst can achieved93.7%、95.21%、98.50%after200min in the sameconditions. Similarly, PMoV₁/PANI/TiO₂catalyst degradation under the best conditions witha high catalytic activity of the gentian violet as follwes: initial concentration and pH value of5mg/L and4, respectively, the amount of catalyst0.0075g, the degradation rate reached90.20%after200min.Under the sunlight, degradation rate of catalyst can achieved94.03%after200min in the same conditions. Initial concentration of5mg/L, the amount of catalyst0.0050g, initial pH value of4is the best conditions for PMoV₃/PANI/TiO₂andPMoV₂/PANI/TiO₂catalyst degradation of the gentian violet, degradation rate reached93.01%and96.15%after200min, respectively. Under the sunlight, degradation rate ofcatalyst can achieved96.21%、98.05%after200min in the same conditions. Make use ofPhotocatalytic degradation has vast potential for future development for organicwastewater.Moreover, kinetics feature of photocatalytic degradation of two kinds of dyestuffwhich using PMoV₁/PANI/TiO₂、PMoV₂/PANI/TiO₂and PMoV₃/PANI/TiO₂accord with thekinetics feature of first order reaction.