Fabrication of Cu-Ce/FDU-12 Catalyst with Outstanding NH3-SCR Performance

Al modified FDU-12 molecular sieve (Al-FDU-12) was successfully prepared by hydrothermal method and then Cu/Al-FDU-12 and Cu-Ce/Al-FDU-12 denitrification catalysts were synthesized using the impregnation process. Through experiment investigated was the impact on the NH3-SCR (selective catalytic reduction of NO with NH3 as the reductant) activity of different loadings of active component. The sulfur tolerance of the catalyst was also investigated. The results exhibited that the optimal loadings of Cu and Ce were 20 and 10%, respectively. The NOx conversion of Cu20Ce10/Al-FDU-12 reached 80%, while its N-2 selectivity was over 99% at 250 degrees C. The addition of Ce can improve the redox characteristics as well as the amount of surface chemisorbed oxygen, which facilitated the "FAST SCR" reaction. In addition, Cu+ is preferentially oxidized to form Cu2+, NOx is combined with Cu2+ to form the active intermediate Cu2+-NxOy and further reacts with NH3 to generate N-2 and H2O, yet Cu+, thus promoting the catalytic cycle. What's more, the catalyst had good catalytic activity when SO2 was introduced.