What determines the catalyst's selectivity in the ethylene epoxidation reaction

被引：70

作者：

Kokalj, Anton ^{[1
,2
,3
]}

Gava, Paola ^{[2
,3
]}

de Gironcoli, Stefano ^{[2
,3
]}

Baroni, Stefano ^{[2
,3
]}

机构：

[1] Jozef Stefan Inst, SL-1000 Ljubljana, Slovenia

[2] SISSA, I-34014 Trieste, Italy

[3] CNR DEMOCRITOS Theory Electrra Grp, INFM, I-34014 Trieste, Italy

来源：

JOURNAL OF CATALYSIS | 2008年 / 254卷 / 02期

关键词：

ethylene epoxidation; C-H activation; density functional calculations; heterogeneous catalysis; reaction mechanisms;

D O I：

10.1016/j.jcat.2008.01.008

中图分类号：

O64 [物理化学（理论化学）、化学物理学];

学科分类号：

070304 ; 081704 ;

摘要：

The selectivity of a catalyst in ethylene epoxidation reaction was addressed using quantum mechanical computer simulations. We found that the catalyst's selectivity in the reaction of oxametallacycle to form ethylene epoxide (EO) rather than the competing acetaldehyde (Ac) is determined in part by the differential bonding affinity of the catalyst toward the O and C atoms of the oxametallacycle. This interplay between O- and C-metal bond strength is due to the different structures of the two transition states. Based on this finding, we introduce a new indicator that determines the difference between the EO and Ac activation energies in the oxametallacycle reaction remarkably well for a number of different materials. (C) 2008 Elsevier Inc. All rights reserved.

引用

页码：304 / 309

页数：6

共 45 条

[1]

[Anonymous], HDB HETEROGENEOUS CA

[2]

Baroni S., 2005, PWSCF PHONON PLANE W

[3] Surface science and the advancement of direct olefin epoxidation. A perspective on the article, Partial oxidation of higher olefins on Ag(1 1 1) and Ag(1 1 0): Conversion of styrene to styrene oxide, benzene, and benzoic acid, by Andreas Klust and Robert J. Madix [J].

Center for Catalytic Science and Technology, Department of Chemical Engineering, University of Delaware, Newark, DE 19716, United States .

Surf Sci, 2006, 23 (5021-5023)

[4] Ethene epoxidation selectivity inhibited by twisted oxametallacycle: A DFT study on Ag surface-oxide [J].

Bocquet, ML ;

Loffreda, D .

JOURNAL OF THE AMERICAN CHEMICAL SOCIETY, 2005, 127 (49) :17207-17215

[5] New insights into ethene epoxidation on two oxidized Ag {111} surfaces [J].

Bocquet, ML ;

Michaelides, A ;

Loffreda, D ;

Sautet, P ;

Alavi, A ;

King, DA .

JOURNAL OF THE AMERICAN CHEMICAL SOCIETY, 2003, 125 (19) :5620-5621

[6] OXIDATION OF TERT-BUTYL ALCOHOL TO ISOBUTYLENE OXIDE ON A AG(110) SURFACE - THE ROLE OF UNACTIVATED C-H BONDS IN PRODUCT SELECTIVITY [J].

BRAINARD, RL ;

MADIX, RJ .

JOURNAL OF THE AMERICAN CHEMICAL SOCIETY, 1989, 111 (11) :3826-3835

[7] EPOXIDES AS PROBES OF OXAMETALLACYCLE CHEMISTRY ON RH(111) [J].

BROWN, NF ;

BARTEAU, MA .

SURFACE SCIENCE, 1993, 298 (01) :6-17

[8] Bonding and reactivity of styrene on Cu(110): heterogeneous alkene epoxidation without the use of silver [J].

Cowell, JJ ;

Santra, AK ;

Lindsay, R ;

Lambert, RM ;

Baraldi, A ;

Goldoni, A .

SURFACE SCIENCE, 1999, 437 (1-2) :1-8

[9] Efficient epoxidation of a terminal alkene containing allylic hydrogen atoms:: trans-methylstyrene on Cu{111} [J].

Cropley, RL ;

Williams, FJ ;

Urquhart, AJ ;

Vaughan, OPH ;

Tikhov, MS ;

Lambert, RM .

JOURNAL OF THE AMERICAN CHEMICAL SOCIETY, 2005, 127 (16) :6069-6076

[10] Density-functional perturbation theory with ultrasoft pseudopotentials [J].

Dal Corso, A .

PHYSICAL REVIEW B, 2001, 64 (23)

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