采用完全液相法制备了Cu-Zn-Al双功能浆状催化剂,利用不同类型表面活性剂对其进行了修饰和改性.通过N2气吸附、XRD和XPS等方法考察了表面活性剂类型对催化剂织构、物相以及表面性质的影响,采用浆态床反应装置对其合成气一步法制备二甲醚的催化活性进行了评价,讨论了催化剂结构与性能的关系.结果表明,表面活性剂主要是通过与活性金属的作用调节催化剂的表面性质、孔结构、相结构以及晶粒大小,进而影响催化剂的催化活性;非离子表面活性剂总体上对催化剂的性能有促进作用,阳离子表面活性剂和阴离子表面活性剂对催化剂性能存在不利影响;表面活性剂与活性金属作用的强弱是影响性能的关键.
A series of Cu-Zn-Al bifunctional slurry catalysts were prepared via the complete liquid-phase technology with different surfactants as the modifiers. The catalysts were characterized with N2 adsorption, XRD and XPS, and the catalytic activity of the catalysts for direct synthesis of DME from syngas was evaluated in a slurry reactor. The effect of different kinds of surfactants on catalyst structure and performance was investigated. The results show that the surfactants can adjust specific surface area, pore structure, phase structure and crystalline size of the catalysts by acting with active metal mainly, thereby affect the catalytic activity of the catalysts. Nonionic surfactant can promote catalytic performance of the catalyst, cationic and anionic surfactants are unfavorable for the catalyst. The intensity of the function between surfactant and active metal is the key that has influence catalytic performance.