| 초록 |
XPS, EPR, in situ FTIR and reaction tests were performed to investigate the surface species during SCR-NO by i-C4H10 in the presence of SO2 over Fe-ZSM5. From the kinetic studies at 623K, it was shown that a presence of SO2 in the reaction mixture strongly poisoned Fe-ZSM5. XPS studies of deactivated Fe-ZSM5 revealed the formation of sulfate and sulfite species. EPR data showed that SO2 decreased the intensity of the peak arising from the most coordinatively unsaturated Fe3+ ions at g=5.8 and g=6.5 and created a new and sharp peak at g=1.9978 tentatively assigned to paramagnetic coke species. In the presence of SO2, the intensities of the ir bands arising from Fe-NO2 (1623cm-1) and Fe-NO3 (1573cm-1) decreased. On the basis of these results, SO2 deactivated Fe-ZSM5 by suppressing the formation of Fe-NO2 complex and increasing the formation of carbonaceous deposits. |
