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The effects of H2O and residue SO2 in flue gases on the activity of the Fe/zeolite catalysts for low-temperature NH3-SCR of NO were investigated. And the addition effect of Mn, Zr and Ce to Fe/zeolite for low-temperature NH3-SCR of NO in the presence of H2O and SO2 was investigated. Fe/zeolite catalysts were prepared by liquid ion exchange and promoted Fe/zeolite catatysts were prepared by liquid ion exchange and doping of Mn, Zr and Ce by incipient wetness impregnation. Zeolite NH4-BEA and NH4-ZSM-5 were used to adapt the SCR technology for mobile diesel engines. The catalysts were characterized by BET, X-ray diffraction (XRD), SEM/EDS, TEM/EDS. The NO conversion at 200 ℃ over Fe/BEA decreased from 77% to 47% owing to the presence of 5% H2O and 100 ppm SO2 in the flue gas. The Mn promoted MnFe/BEA catalyst exhibited NO conversion higher than 53% at 200 ℃ and superior to that of Fe/BEA in the presence of H2O and SO2. The addition of Mn increased the Fe dispersion and prevented Fe aggregation. The promoting effect of Mn was higher than Zr and Ce. Fe/BEA catalyst exhibited good activity in comparison with Fe/ZSM-5 catalyst at low temperature below 250 ℃.

주제어 : 메탄, 부분산화, 수소생산, 촉매, 조촉매 Abstract : The Co and Ni catalysts supported on Al2O3 for partial oxidation of methane producing hydrogen were synthesized using impregnation to incipient wetness. And the promotion effects of metals such as Mg, Ce, La and Sr in partial oxidation of methane over these Co/Al2O3 and Ni/Al2O3 were investigated. Reaction activity of these catalysts for the partial oxidation of methane was investigated in the temperature range of 450~650 ℃ at 1 atm and CH2/O2 = 2.0. The catalysts were characterized by BET, XRD and SEM/EDX. The results indicated that the catalytic performance of these catalysts was improved with the addition of 0.2 wt% metal promoter. The Mg promoted Co/Al2O3 catalyst showed the highest CH4 conversion and hydrogen selectivity at higher temperature than 500 ℃. The Ce and Sr promoted Ni catalysts superior to Co-based catalysts in the low temperature range. The addition of metal promoter to Co/Al2O3 and Ni/Al2O3 catalysts increased the surface area.

:The NH3-selective catalytic reduction (SCR) reaction of NO with excess of oxygen were systematically investigated over Cu-zeolite and Fe-zeolite catalysts. Cu-zeolite and Fe-zeolite catatysts to adapt the SCR technology for mobile diesel engines were prepared by liquid ion exchange and incipient wetness impregnation of NH4-BEA and NH4-ZSM-5 zeolites. The catalysts were characterized by BET, XRD, FE-TEM (field emission transmission electron microscopy) and SEM/EDS. The SCR examinations performed under stationary conditions showed that the Cu-exchanged BEA catalyst revealed pronounced performance at low temperatures of 200-250 ℃. With respect to the Fe-zeolite catalyst, the Cu-zeolite catalyst showed a higher activity in the SCR reaction at low temperatures below 250 ℃. BEA zeolite based catalyst exhibited good activity in comparison with ZSM-5 zeolite based catalyst at low temperatures below 250 ℃.

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