Ce添加量对Cu-Ce/MgO催化合成气制低碳醇性能的影响

采用共浸渍法制备不同Ce含量(相对于MgO的摩尔分数为0~15%)的Cu-Ce/MgO催化剂,采用X射线衍射(XRD)、N_2物理吸附(N_2-adsorption)等手段对催化剂的结构进行表征,并在连续流动微型固定床反应器中考察其催化CO加氢合成低碳混合醇的反应性能.结果表明,不同含量的Ce助剂的添加对催化剂的物理结构、表面物相以及醇的选择性和产物分布都产生一定的影响.当Ce的负载量为10%时,催化剂样品的比表面积达到最大(64.23m2·g~(-1)),CO的转化率较高(42.3%),醇的选择性最高(43.7%),CHx的选择性最低,催化剂的活性最高.

Effect of cerium addition on the catalytic performance of Cu-Ce/MgO for synthesis of lower alcohols from syngas

A series of Cu-Ce/MgO catalysts with different Ce contents(mole fraction relative to MgO:0～ 15 ％)were prepared by co-impregnation method,and the structure and surface properties of Cu-Ce/MgO catalysts were characterized by nitrogen adsorption,XRD,and their catalytic performances for CO hydrogenation to lower alcohols were investigated using a continuous flow fixed bed micro-reactor.The results indicated that the physical structure and surface phase are affected by different catalyst additives,especially the specific surface area and the dispersion,and the selectivity and product distribution of the alcohols are significantly affected.At a Ce content of 10％,the catalyst had the highest BET surface area(64.23m2 · g 1),the higher CO conversion (42.3％),the highest selectivity of higher alcohols(43.7％) and lowest selectivity of hydrocarbons,the catalytic activity of the catalyst was highest.