Preparation Of BaZrO₃Catalyst With Red Mud As Carrier And Its Catalystic Properties For No Oxidation

Red mud produced as by-product from the production of aluminum oxide is a kind of waste material. It has been reported that the output of red mud in China has reached about11%over the world. Large amount of red mud has caused pollution of the environment and harmed the human’s life. How to reutilize the solid waste has become an interesting research subject in the current.NOx are considered to be the primary pollutants of the atmosphere, since they are responsible for environmental problems like photochemical smog, acid rain, and ozone destruction. Acid rain is a further environmental pollution which may do harm to vegetation, soil, and lead to water acidification. Researchers are looking forward to obtain more efficient techniques to deal with NOx.This study is mainly about analysis of red mud and the catalyst of denitration,including the preparation method of the catalyst and its supporter, and the catalytic oxidation performance about NO in flue gas. The major studies are as follows:(1) Anaylsis the physical appearance and internal of red mud by SEM, XRD, FIR. The main material quality:SiO2accounted for22.96%, MgO accounted for2.15%, CaO accounted for45.77%, Al2O3accounted for12.53%, Fe2O3accounted for15.86%, K2O accounted for1.27%. Meanwhile, hematite, hydration garnet, hydrated sodium silicate, calcium silicate, as well as calcite form the main constituent of the red mud.(2) Mixing with fly ash and other things, red mud as the main material was sintered to a carrier of ceramic. Based on the others research results, this paper puts forward a reasonable experimental plan, which studied performance of the carrier made in different condition by measuring the blowhole rate,stomata distribution and compressive strength. It turned out that when sintering temperature range is750℃-800℃, red mud ceramsite supporter’s. blowhole rate is about60%and compressive strength performance is above3MPa,we can synthetise the most ideal catalyst.(3) The experiment produced a kind of catalyst-BaZrO3by sol-gel, which was loaded to the carrier after different temperature sinteringand examined the factors such as temperature and PH to the influence of catalyst preparation to optimize the method. Through the analysis of XRD and SEM,it showed that we could get the ideal catalyst,the cube crystal structure of the catalyst and perovskite structure,in the sintering temperature in750℃-800℃.The result shows that the ideal catalyst has excellent activity,layer structure,full of pore structure and the magnificent specific surface area,which benefit the fully contact between the catalyst and the gas.(4) This paper study on the catalytic oxidation performance of different BaZrO3vector formula. It choose good vector formula of red mud:fly ash:bentonite=5:4:1and study, under the different experimental conditions,such as temperature, space velocity and the oxygen content, the catalytic oxidation performance of the composite catalyst. The result is that in the space velocity of12000h-1,O2content20%, catalyst content20%,500ppm NO, using N2as equilibrium condition, the conversion of NO can reach nearly40%.