Toluene disproportionation and coking on zeolites Y modified with Lewis-connected InO+ acid sites

V. Mavrodinova, M. Popova, R. M. Mihályi, G. Pál-Borbély, Ch Minchev

Research output: Contribution to journalArticle

9 Citations (Scopus)

Abstract

The effect of introduction of Lewis acid sites on the reactions of toluene transformation and catalysts coking has been studied over parent (Si/Al = 2.5) and dealuminated (Si/Al = 3.7) Y zeolites modified with Lewis connected InO + cationic acid sites. The catalysts with prevalent amount of Brönsted acid sites (less than 40% of protons exchanged by InO+) possess the typical for the proton directed reaction of methyl transfer upon toluene disproportionation long period of activation, the longer the higher the concentration of bridging protons. In contrast, at predominant Lewis sites concentration, the activation period disappear, an enhanced initial activity is observed, followed by deactivation on the expense of a rapid process of accumulation of strongly held reaction products and intermediates. Their further condensation leads to catalysts aging, the faster the higher the concentration of electron acceptor Lewis acid sites. A relation has been found between the initially accelerated processes of alkyl transfer and the reinforced formation of carbonaceous deposits over the In-modified catalysts.

Original languageEnglish
Pages (from-to)239-246
Number of pages8
JournalJournal of Molecular Catalysis A: Chemical
Volume220
Issue number2
DOIs
Publication statusPublished - Oct 11 2004

Keywords

  • Coking
  • InO counterions
  • Lewis acidity
  • Toluene disproportionation

ASJC Scopus subject areas

  • Catalysis
  • Process Chemistry and Technology
  • Physical and Theoretical Chemistry

Fingerprint Dive into the research topics of 'Toluene disproportionation and coking on zeolites Y modified with Lewis-connected InO<sup>+</sup> acid sites'. Together they form a unique fingerprint.

  • Cite this