| 초록 |
The selective catalytic reduction (SCR) of nitrogen oxides (NOx) with NH3 is among the state of the art technologies that applied to various combustion systems. Although V2O5 supported catalysts have been widely used commercially, some disadvantage still remain such as relatively narrow operating window (300~400℃) and the formation of N2O at high temperature. Recently, CeO2 based catalysts attracted a lot of research group due to its superior N2 selectivity and wide temperature window. In this study, commercially available CeO2 powder and TiO2 which contains SO3 (~1.25wt%) species was mechanically mixed by using porcelain mortar followed by simple calcination step. Interestingly, mechanical mixture showed excellent SCR activity and N2 selectivity in wide temperature range (250~500℃). X-ray diffratction, FT-IR, Temperature programmed reduction technique, SEM and EDS were used to investigate the interaction between TiO2 and CeO2 particles. Based on these techniques, we found that thermal treatment induce migration of sulfur species from TiO2 to CeO2 region, thereby promoting SCR reaction at high temperature. |
