One-pot hydrothermal synthesis of CuBi co-doped mesoporous zeolite Beta for the removal of NO x by selective catalytic reduction with ammonia

A series of CuBi co-doped mesoporous zeolite Beta (Cu x Bi y -mBeta) were prepared by a facile one-pot hydrothermal treatment approach and were characterized by XRD, N 2 adsorption-desorption, TEM/SEM, XPS, H 2 -TPR, NH 3 -TPD and in situ DRIFTS. The catalysts Cu x Bi y -mBeta were applied to the removal of NO x by selective catalytic reduction with ammonia (NH 3 -SCR), especially the optimized Cu 1 Bi 1 -mBeta achieved the high efficiency for the removal of NO x and N 2 selectivity, superior water and sulfur resistance as well as good durability. The excellent catalytic performance could be attributed to the acid sites of the support and the synergistic effect between copper and bismuth species. Moreover, in situ DRIFTS results showed that amides NH 2 and NH 4 + generated from NH 3 adsorption could be responsible for the high selective catalytic reduction of NO x to N 2. In addition, a possible catalytic reaction mechanism on Cu 1 Bi 1 -mBeta for the removal of NO x by NH 3 -SCR was proposed for explaining this catalytic process.