Experimental Research On Selective Catalytic Reduction Of NO By Mn-Ce-CuOx/ACFat Low Temperature

There is a serious problem of the air pollution which the nitrogen oxide have a largeproportion, because the development of industry and the more and more families buyprivate cars. It caused great harm to the ecological environment and human health. Weintroduced the source, the harm, the mechanism of formation and the present control ofnitrogen oxide in this paper. And summarize the control technology of NOx and itsdevelopment. It is one of the typical effective methods of denitration in flue gas currently,which used NH3as reductant in low-temperature development direction in the selectivecatalytic reduction (SCR). We also discussed the research present situation and trend ofSCR catalysts. This topic researched a new catalyst in SCR and investigated itsperformance.A series of catalysts which have different load ratio were prepared by impregnationmethod. Under the condition of simulation flue gas in the laboratory, the research showsthat the catalyst Mn-Ce-CuOx/ACF which load ratio was20%and the mass ratio of Mn,Ce and Cu was1:1:1has the best catalytic performance. This catalyst exhibited relativelyhigh catalytic activity and yielded98%NO conversion at240℃with a space velocity of10000h-1and the dose of catalyst was0.5g, the temperature range was80~360℃. Thesimulated flue gas was composed of1000ppm NO,1100ppm NH3,5%O2(volumefraction) and N2as balance gas.After the optimization formula of the catalyst, the influence of NO concentration, H2Oand SO2were examined. And the life of the catalysts was tested. The results showed thatthe NO concentration has certain but little effect, the H2O has the poison impact oncatalysts, but to be mild and reversible, which indicated the catalyst has good waterresistance. According to the experiment, low concentration of SO2on catalyst has apromoting effect, but high concentration can make the catalyst inactivation and irreversible.In the case of a poisoning, the catalyst can keep70%of the denitration efficiency.The catalysts were characterized by means of N2adsorption measurement (BET),scanning electronic microscopy (SEM), transmission Fourier transform infrared (FTIR),X-ray diffraction (XRD) and X-ray photoelectron spectroscopy (XPS) experiment.According to the results, we can find that metal oxide has better distribution in the surfaceof carrier and have various valence of the metal, which can promote the catalytic reaction.On the base of activity experiment and the analysis of characterization, we probed the selective catalytic reduction mechanism of NO.