Cs/CuAl-LDO@X催化剂制备及甲苯侧链烷基化反应性能

Preparation of Cs/CuAl-LDO@X catalysts and its performance in side-chain alkylation of toluene

以X分子筛为载体,在其表面生长CuAl-LDH层状氢氧化物,浸渍Cs后焙烧,制备了一系列不同CuAl-LDO含量的Cs/CuAl-LDO@X催化剂。采用XRD、SEM、NH 3-TPD和CO 2-TPD手段对催化剂结构进行了表征,并在固定床微反应器上评价了催化剂的甲苯侧链烷基化一步制苯乙烯的反应性能。结果表明,在Cs/CuAl-LDO@X催化剂中,X分子筛表面的CuAl-LDO呈现花簇状二维层状结构;随着CuAl-LDO含量的增加,催化剂的酸、碱活性中心有一定量的增加;不同CuAl-LDO含量的催化剂对甲苯侧链烷基化反应都具有良好的催化性能,其中CuAl-LDO含量为16.6%(质量分数)的Cs/CuAl-LDO-3@X催化剂具有最好的催化性能,在甲苯转化率为4.78%时,苯乙烯选择性为46.91%.

Using X zeolite as a carrier,CuAl-LDH was grown on the surface of the carrier,and a series of Cs/CuAl-LDO@X catalysts with different CuAl-LDO contents were prepared after impregnating Cs and roasting.The structure of the catalysts were characterized by XRD,SEM,NH 3-TPD and CO 2-TPD.The catalytic performance of the catalyst in side-chain alkylation of toluene with methanol on one step to the styrene was evaluated in a fixed-bed microreactor.The results showed that in the Cs/CuAl-LDO@X catalysts,the CuAl-LDO on the surface of X zeolite showed a flower cluster-like two-dimensional layered structure.The amount of acid and base active centers of the catalysts increased with the increase of CuAl-LDO content.The catalysts with different CuAl-LDO contents all had good catalytic performance for the toluene side-chain alkylation reaction.The Cs/CuAl-LDO-3@X catalyst with CuAl-LDO mass fraction of 16.6%had the best catalytic performance.When toluene conversion was 4.78%,the selectivity of styrene was 46.91%.