不同孔结构CeTiOx催化剂的制备及其NH3-SCR脱硝性能研究OACSTPCD

To investigate the influence of pore structure on the catalytic activity of catalysts,four catalysts including three-dimensionally ordered macroporous-mesoporous(3DOM-m)CeTiOx,three-dimensionally ordered macroporous(3DOM)CeTiOx,three-dimensionally ordered mesoporous(3DOm)CeTiOx and disordered mesoporous(DM)CeTiOx were synthesized by the sol-gel method.The NH3-SCR denitration testing results show that the performance of the catalysts with different pore structures follows the sequence of 3DOM-m CeTiOx＞3DOm CeTiOx＞3DOM CeTiOx＞DM CeTiOx,and the 3DOM-m CeTiOx shows an excellent catalytic activity,with more than 90％ NO conversion in the range of 250-400 ℃ at a GHSV of 60000 h-1.The characterization of catalysts by XRD,SEM,BET,NH3-TPD and in-situ DRIFTS indicates that the surface area is not the dominant factor determining the catalytic activity of CeTiOx.3DOM-m CeTiOx has a highly ordered macroporous-mesoporous structure and abundant Bronsted acidic sites,thereby improving the denitrification activity.The NH3-SCR reaction over the 3DOM-m CeTiOx mainly follows the L-H and E-R mechanisms.