Application of surfactant-modified cordierite-based catalysts in denitration process

摘要

The Mn-based oxides and Cu-based oxides were used as active components. They were supported on the honeycomb ceramic cordierite carrier and the carrier was modified by the surfactant TEP (Double palm carbox-yethyl-hydroxyethylmethyl sulfateammonium salt). By changing the interventional position of the surfactant, it was contrasted the influence of the presence or the absence of TEP on the dispersibility of the metal oxides and the denitration performance of the catalyst. It was characterized the catalyst activity by XPS, TPR, SEM and FITR. The reaction activation energy was calculated by reaction kinetics to further clarify the denitration mechanism of the catalyst. The results indicated that TEP could increase the impregnation of the catalyst and make the dispersion of metal oxide more uniform. And the denitration efficiency of MnOX/TEP + CuOX + TEP (MTCT) catalyst was higher than others. According to the surface reaction Arrhenius equation, the activation energy of MTCT catalyst was 85.39 kJ/mol while that of MnOX-CuOX (MC) catalyst was 118.71 kJ/mol. The MTCT catalyst greatly reduced the activation energy of the NO oxidation reaction and was beneficial to the progress. Therefore, TEP had a significant effect on the denitration efficiency of cordierite catalysts.