175
Views
6
CrossRef citations to date
0
Altmetric
Articles

A multi-scale computational study on the mechanism of protonation of isobutene and 2-butene over HY zeolite

ORCID Icon, , , &
Pages 1348-1355 | Received 14 Feb 2017, Accepted 09 Jul 2017, Published online: 25 Jul 2017
 

Abstract

To understand the alkylation mechanism of isobutane with butene, it is of great importance to elucidate the difference of protonation behaviours among butene isomers at molecular scale, because it is the starting point of this reaction. Herein, we have calculated the protonation processing of isobutene and 2-butene on a 120T HY cluster model, using an embedded QM/MM (quantum mechanical/molecular mechanical) method. The formation energy of π-complex from isobutene is higher than that of 2-butene owing to the effect of electronic interaction and steric hindrance between the C=C bond of butene and the H atom of the HY zeolite. Moreover, the energy of t-butyl alkoxide (TBA) produced via isobutene protonation is higher than that of s-butyl alkoxide (SBA) from 2-butene, as the C–O bond of TBA is longer. In addition, the transition state of isobutene protonation is a t-butyl carbonium ion, while the corresponding structure during 2-butene protonation is a s-butyl carbonium ion, which is less stable. In conclusion, isobutene is much easier to be activated by Brönsted acid site of HY zeolite than 2-butene.

Acknowledgement

We gratefully acknowledge the warm-hearted supports from Dr. Xia Changjiu at RIPP.

Log in via your institution

Log in to Taylor & Francis Online

PDF download + Online access

  • 48 hours access to article PDF & online version
  • Article PDF can be downloaded
  • Article PDF can be printed
USD 61.00 Add to cart

Issue Purchase

  • 30 days online access to complete issue
  • Article PDFs can be downloaded
  • Article PDFs can be printed
USD 827.00 Add to cart

* Local tax will be added as applicable

Related Research

People also read lists articles that other readers of this article have read.

Recommended articles lists articles that we recommend and is powered by our AI driven recommendation engine.

Cited by lists all citing articles based on Crossref citations.
Articles with the Crossref icon will open in a new tab.