The denitration mechanism of fly ash catalysts prepared by low-temperature plasma technology

Abstract

In this paper, fly ash-based catalysts were supported by equivalent-volume impregnation method and roasted with low-temperature plasma technology. This technology has the advantages of short treatment time, lower energy consumption, and well-distributed active components. Therefore, the plasma power, plasma time, oxygen flow rate and metal loading condition in the denitration process were studied at sub-atmosphere ambient gas processing conditions. Different types of fly ash, modification conditions and loading conditions in the denitration process were studied. BET, XRD, SEM and XPS were used to characterize the catalysts, and the effect of the structure and performance of catalysts during the catalytic activity of the catalysts were further determined. The results were: The manganese metal and cerium metal were successively loaded in the catalyst and then roasted in low temperature plasma with oxygen. The two metals had a synergistic effect on forming P-type semiconductors, which significantly improved the performance of denitration. MnO2 and CeO2 played a major role in denitration. The fly ash-based catalyst with the preliminary modification and then loaded metal oxides not only maintained effective denitration performance, but also greatly improved the sulfur resistance, and had a positive effect on extending the service life of catalysts.