Cu-Mn-Zn/Y直接合成二甲醚催化剂中锌和锰的协同调节作用

通过对Y型分子筛负载Cu-Mn、Cu-Zn和Cu-Mn-Zn催化剂的结构、表面性质及其直接合成二甲醚反应活性的对比,发现Mn和Zn对催化剂还原性能的影响作用相反,对催化剂吸附H₂和CO的影响也不同。Mn和Zn的单独添加或共同添加引起催化剂结构和组分之间相互作用程度的改变,是造成催化剂活性和选择性变化的主要原因。两者的协同作用,能调整催化剂的还原性能和吸附性能达到适合的状态,从而使得催化剂具有高的二甲醚合成活性。

Synergistic effect of zinc and manganese in Cu-Mn-Zn/Y catalyst for syngas-to-dimethyl ether

Cu-Mn,Cu-Zn and Cu-Mn-Zn supported on zeolite Y were tested for the synthesis of dimethyl ether(DME) directly from synthesis gas in a fixed-bed reactor,and characterized by means of H2-TPR,XRD and TPD.The results showed that Zn was beneficial to the reducibility and H2 chemiadsorption of the catalysts,but decreased the ability of CO chemiadsorption;Mn was beneficial to CO adsorption,but decreased the reducibility and ability of H2 chemisorption.Thus,the synergic effects of Zn and Mn in Cu-Mn-Zn/zeolite-Y catalyst grew more and stronger adsorption sites of H2 and CO,made a favorable catalyst for direct DME synthesis.Consequently,the Cu-Mn-Zn/zeolite-Y catalyst exhibited the best catalytic performance for direct synthesis of DME was duo to the synergic effects of Zn and Mn to the proper adsorption ability of H2 and CO.