Summary: | 碩士 === 國立成功大學 === 化學工程學系碩博士班 === 90 === Activated carbons with nitrogen functional group will make use of selective catalytic reduction (SCR). Carbons with well-controlled nitrogen contents were prepared from phenol-formaldehyde resins impregnated with different amounts of urea and m-phenylenediamine. The performance of these carbon catalysts for selective catalytic reduction (SCR) of nitric oxide by ammonia were investigated. The chemical compositions of the resin precursors and the resulting carbons well characterized using various analytical techniques. Elemental analysis of the chars from the urea-impregnated resins showed very little presence of nitrogen. For impregnating m-phenylenediamine there are nitrogen functional group in phenol-formaldehyde resins, and in this research we discussed the carbons with m-phenylenediamine in selective catalytic reduction (SCR). The heteroatoms, N and O, in the carbons were found to be more populated in small pores. The catalytic activity of the carbons in NO reduction of NH3 increased because of the nitrogen impregnation. The activity showed a close correlation with the nitrogen content obtained with X-ray photoelectron spectroscopy, indicating that the reaction mainly occurred in larger pores. In the low temperature regime (< 140°C), the reaction was dominated by the adsorption, which rendered a negative apparent energy, while surface interactions controlled the reaction at higher temperatures. The impregnated nitrogen atoms were found to promote the adsorption of NO, as well as to accelerate the interactions between the adsorbed species.
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