期刊
JOURNAL OF CATALYSIS
卷 269, 期 2, 页码 351-358出版社
ACADEMIC PRESS INC ELSEVIER SCIENCE
DOI: 10.1016/j.jcat.2009.11.018
关键词
Sulfated zirconia; Isomerization; Microcalorimetry; n-Butane; Isobutane; Adsorption isotherm
资金
- Deutsche Forschungsgemeinschaft [1091, 267/01]
- Max Planck Society
A method to characterize the surface sites of catalysts in their active state by adsorption microcalorimetry was developed. A calorimeter cell was used as a flow-type reactor, and the skeletal isomerization of n-butane (1 kPa) at 378 K and atmospheric pressure proceeded at comparable rates and with the same states of induction period, maximum and deactivation phase as in a tubular reactor. The reaction was run for selected times on stream and after the removal of weakly adsorbed species, n-butane or isobutane were adsorbed at 313 K. The surface of activated sulfated zirconia was characterized by at least two different sites for n-butane adsorption, a small group of sites (about 20 mu mol g(-1)) that yielded heats of 50-60 kJ mol(-1) and sites that were populated at higher pressures (above about 5 hPa n-butane) and yielded heats of about 40 kJ mol(-1). The strongly interacting sites disappear during the induction period and are proposed to be the sites where the isomerization reaction is initiated. (C) 2009 Elsevier Inc. All rights reserved.
作者
我是这篇论文的作者
点击您的名字以认领此论文并将其添加到您的个人资料中。
推荐
暂无数据