Direct synthesis of DME over bifunctional catalyst: surface properties and catalytic performance
Direct synthesis of DME over bifunctional catalyst: surface properties and catalytic performance
复制标题
DOI：
10.1016/s0926-860x(03)00466-6
复制
发表时间：
2003-10-15
影响因子：
5.5
通讯作者：
Xu, XL
中科院分区：
文献类型：
--
作者：
Sun, KP;Lu, WW;Xu, XL
制备了一系列不同ZrO 2含量的CuO/ZnO/ZrO 2/HZSM-5双功能催化剂，并通过比表面积、XRD和XPS分析对其进行了表征。在STD工艺（合成气制二甲醚）的开发中对该催化体系进行了评价。基于这些结果，可以推断，引入CuO晶格中的ZrO 2导致在还原过程中在催化剂表面上形成Cu+，这似乎是在本研究中的二甲醚（DME）和CO转化的高选择性的关键。ZrO 2对催化剂表面结构如Cu/Zn比和Cu浓度的影响与催化剂的二甲醚合成活性密切相关。此外，双功能催化剂中两种活性组分分散均匀，相互间保持紧密接触，对CO转化为DME具有高度的“协同效应”。综上所述，Cu+/Cu-0/Zn（2-delta）+/Zn ~（2+）/ZrO_2/HZSM-5被认为是直接合成DME的表面活性态。(C)2003 Elsevier B. V.保留所有权利。
A series of bifunctional catalysts CuO/ZnO/ZrO2/HZSM-5 with different ZrO2 contents were prepared and characterized by surface area, XRD and XPS analysis. The catalytic system was evaluated in the development of STD process (synthesis gas-to-dimethyl ether). Based on these results, it was deduced that the incorporation of ZrO2 in CuO lattice caused the formation of Cu+ on the catalyst surface during reduction, which seems to be crucial for the high selectivity of dimethyl ether (DME) and CO conversion in the present study. Also, the promoting effect of ZrO2 on the surface structure, such as Cu/Zn ratio and Cu concentration, was closely related to the DME synthesis activity. In addition, two kinds of active components in the bifunctional catalysts are finely dispersed, maintain close contact, and consequently exhibit a high degree of 'synergistic effect' for the effective conversion of CO to DME. In summary, Cu+/Cu-0/Zn(2-delta)+/Zn2+/ZrO2/HZSM-5 is considered to be the surface active state for the direct synthesis of DME. (C) 2003 Elsevier B.V. All rights reserved.