La促进CuCo催化剂上合成气转化制低碳醇的研究

利用超声辅助的反相共沉淀法制备了合成气选择转化制低碳醇用CuCo基催化剂。研究稀土La助剂对CuCo基复合氧化物催化剂结构的影响和催化性能的促进作用,借助X射线衍射(XRD)、N₂吸附等温线(BET)和程序升温脱附(CO-TPD)等测试技术对催化剂进行表征,并以CO加氢合成低碳醇为模型反应对其催化性能进行评价。结果表明,La助剂的添加使催化剂晶粒细化,显著加大了比表面积,促进了合成醇活性位的形成,提高了催化剂表面较强吸附CO物种的浓度,从而明显提高催化剂的活性与C_2＋醇选择性,有效调节了低碳混合醇中甲醇的含量。

Studies on higher alcohols from syngas over the La promoted CuCo catalysts

CuCo-based catalysts for the synthesis of higher alcohols from syngas were prepared by the ultrasound assisted reverse coprecipitation.The effects of rare earth La promoter on the structure and catalytic performance were investigated.The catalysts were systematically characterized by means of X-ray diffraction(XRD),N2 adsorption isotherm(BET) and temperature-programmed desorption(CO-TPD) techniques.The catalytic performance for CO hydrogenation to higher alcohols was also evaluated.The experimental results showed that with the addition of La,the crystal size of the sample was decreased,the specific surface area was increased notably,the formation of the active sites for alcohol formation was improved and the concentration of more strongly adsorbed CO-species was increased.Therefore,the catalytic activity and higher selectivity to C2+ alcohols were improved obviously,and the content of methanol in mixed alcohols was reduced significantly.