Stability of the Reaction Intermediates of Ethylbenzene Disproportionation over Medium-Pore Zeolites with Different Framework Topologies: A Theoretical Investigation
Stability of the Reaction Intermediates of Ethylbenzene Disproportionation over Medium-Pore Zeolites with Different Framework Topologies: A Theoretical Investigation
复制标题
不同骨架拓扑中孔沸石上乙苯歧化反应中间体稳定性的理论研究
DOI：
10.1021/jp4089386
复制
发表时间：
2013-11
影响因子：
3.7
通讯作者：
Deng, Feng
中科院分区：
文献类型：
--
作者：
Yi, Xianfeng;Byun, Youngchul;Chu, Yueying;Zheng, Anmin;Hong, Suk Bong;Deng, Feng
主要反应中间体的应变能（即，为了更精确地研究中孔沸石的孔结构对其形成的影响，用密度泛函理论计算了6种不同骨架拓扑结构的10环沸石以及大孔沸石Y上的EB（EB）脱附过程中形成的10种单乙基二苯乙烷（mEDPE）和10种二乙基二苯乙烷（dEDPE）衍生物.发现虽然在Y沸石、MCM-22和TNU-9中mEDPE和dEDPE中间体的应变能总是低于19.6kJ mol（-1），但当它们位于ZSM-5和ZSM-57的交叉通道中时，其中一些的特征在于相当高的能量（> 32.8kJ mol（-1））。此外，正如预期的那样，嵌入具有较窄10环通道的TNU-10和ZSM-22中的所有mEDPE和dEDPE衍生物都强烈扭曲，使它们具有高得多的应变能（>37.7 kJ mol（-1）），这与我们最近报道的实验结果（J. Phys. Chem. C 2010，115，16124）非常一致。这使我们得出结论，中孔沸石中的空隙空间的大小和形状在控制EB纯化过程中mEDPE和dEDPE形成的类型中起着至关重要的作用。我们的工作还表明，应变能的各种反应中间体限制在沸石具有不同的孔拓扑结构可以被视为一个有用的定量手段，在更好地理解这类重要的微孔结晶催化剂的形状选择性的性质。
The strain energies of the main reaction intermediates (i.e., monoethylated diphenylethane (mEDPE) and diethylated diphenylethane (dEDPE) derivatives), which can be formed during ethylbenzene (EB) disproportionation over six 10-ring zeolites with different framework topologies, as well as over the large-pore zeolite Y, were determined by the density functional theory calculations in order to more precisely investigate the effects of the pore structure of medium-pore zeolites on their formations. It was found that while the strain energies of mEDPE and dEDPE intermediates in zeolite Y, MCM-22 and TNU-9, were always lower than 19.6 kJ mol(-1), some of them were characterized by considerably higher energies (>32.8 kJ mol(-1)) when positioned in the intersection channels of ZSM-5 and ZSM-57. As expected, in addition, all the mEDPE and dEDPE derivatives embedded in TNU-10 and ZSM-22 with narrower 10-ring channels were strongly distorted, giving them much higher strain energies (>37.7 kJ mol(-1)), which were in excellent agreements with our recently reported experimental results (J. Phys. Chem. C 2010, 115, 16124). This led us to conclude that the size and shape of void spaces in the medium-pore zeolites play a crucial role in governing the type of mEDPE and dEDPE formations during the EB disproportionation. Our work also shows that the strain energies of various reaction intermediates confined within zeolites with different pore topologies could be regarded as a useful quantitative means in better understanding the shape-selective nature of this important class of microporous crystalline catalysts.
登录
查看更多内容
影响因子：
15
作者：
Clark, LA;Sierka, M;Sauer, J
通讯作者：
Sauer, J
DOI：
10.1016/s0167-2991(97)80729-x
发表时间：
1997
期刊：
Studies in Surface Science and Catalysis
影响因子：
--
作者：
U. Weiss;M. Weihe;M. Hunger;H. Karge;J. Weitkamp
通讯作者：
U. Weiss;M. Weihe;M. Hunger;H. Karge;J. Weitkamp
影响因子：
4.2
作者：
S. Al-Khattaf;N. Tukur;S. Rabiu
通讯作者：
S. Al-Khattaf;N. Tukur;S. Rabiu
影响因子：
12.9
作者：
S. Wannakao;Chompunuch Warakulwit;Kanokwan Kongpatpanich;M. Probst;J. Limtrakul
通讯作者：
S. Wannakao;Chompunuch Warakulwit;Kanokwan Kongpatpanich;M. Probst;J. Limtrakul
影响因子：
2.9
作者：
R. Rungsirisakun;Tanin Nanok;M. Probst;J. Limtrakul
通讯作者：
R. Rungsirisakun;Tanin Nanok;M. Probst;J. Limtrakul