Effect of Cu content on the surface and catalytic properties of Cu/ZrO2 catalyst for ethanol dehydrogenation
Effect of Cu content on the surface and catalytic properties of Cu/ZrO2 catalyst for ethanol dehydrogenation
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DOI：
10.1016/j.molcata.2013.09.038
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发表时间：
2014-01-01
影响因子：
--
通讯作者：
Bueno, J. M. C.
中科院分区：
文献类型：
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作者：
Freitas, I. C.;Damyanova, S.;Bueno, J. M. C.
采用浸渍法制备了不同铜含量(5~30wt.%)的氧化锆负载铜催化剂。研究了乙醇转化反应中铜含量对催化剂结构、表面及催化性能的影响。用N-2吸附-脱附等温线、N2O滴定、X-射线衍射、X-射线光电子能谱、TPR和DRFTS等手段对焙烧和还原样品进行了物化表征。结果表明，随着铜含量的增加，金属颗粒的强烈团聚导致铜的表观弥散度降低。不同反应产物的选择性与催化剂的电子性质有关，这些电子性质由铜的粒度和金属氧化物载体上的界面决定。在铜含量为10wt.%的样品上，乙酸乙酯的选择性最高，这归因于O2-离子碱性中心密度较高以及CO吸附和XPS漂移所定义的铜物种(Cu0/Cu+)更不均匀的分布。(C)2013爱思唯尔B.V.保留所有权利。
ZrO2-supported Cu catalysts with different Cu content (5-30 wt.%) were prepared by impregnation method. The effect of Cu content on the structure, surface and catalytic properties of Cu/ZrO2 catalysts in the reaction of ethanol conversion was studied. The physicochemical characterization of the calcined and reduced samples was carried out by: N-2 adsorption-desorption isotherms, N2O titration, XRD, XPS, TPR and DRFTS of CO adsorption. It was observed that the increase of Cu content leads to decrease of the apparent copper metal dispersion caused by the strong agglomeration of the metal particles. The selectivity to different reaction products was connected with the electronic properties of the catalysts defined by the copper particle size and the interface at metal-oxide support. The highest selectivity to ethyl acetate over samples with Cu content >= 10 wt.% was assigned to the high density of basic sites of O2- ions and more heterogeneous distribution of copper species (Cu-0/Cu+) defined by DRIFTS of CO adsorption and XPS. (C) 2013 Elsevier B.V. All rights reserved.