Origin of Morphology Change and Effect of Crystallization Time and Si/Al Ratio during Synthesis of Zeolite ZSM‐5

Research output: Contribution to journalResearch articleContributedpeer-review

Contributors

Abstract

Hydrothermal synthesis of ZSM-5 is an often applied but incompletely understood procedure. In comparison to current research efforts that aim to produce complex micro-mesoporous catalysts for the conversion of biogenic and bulky hydrocarbons, this work focuses on the dependency between Si/Al ratio and zeolite morphology of microporous ZSM-5 to understand and to control the synthesis process. In two series of time dependent crystallization, kinetics were analyzed at Si/Al ratio 20 and 100 to optimize the crystallization time. Subsequently, zeolites with different Si/Al ratio were obtained and characterized. The results show a transition from a slow dissolution-recrystallization process to a fast solid-state-transformation with increasing Si/Al ratio. This is followed by a switching morphology from clusters of small agglomerates to bigger spherical particles. Respective acid site density and zeolite morphology determine local residence time, hydride transfer behavior and finally selectivity towards aromatics and higher hydrocarbons during methanol conversion. This background should provide control of even more complex syntheses of porous catalysts.

Details

Original languageEnglish
Article numbere202101248
JournalChemCatChem
Volume14
Issue number3
Publication statusPublished - 10 Dec 2021
Peer-reviewedYes

External IDs

Scopus 85122512413
unpaywall 10.1002/cctc.202101248
Mendeley 233cfbb7-aa66-3cc3-bf5a-d43e01e4a82f
WOS 000740879700001
ORCID /0000-0002-8928-8340/work/142235814
ORCID /0000-0001-7523-9313/work/142238561
ORCID /0000-0001-7323-7816/work/142257375

Keywords

Keywords

  • Kinetics, Mechanism of crystallization, ZSM-5, Zeolite morphology, Zeolite synthesis