Origin of First-Order Kinetics during the Bimolecular Cracking of n-Hexane over H-ZSM-5 and H-β Zeolites

Autor:	Michael P. Rosynek, Stefan Kotrel, Jack H. Lunsford
Rok vydání:	2000
Předmět:	Reaction mechanism Chemistry Kinetics Analytical chemistry Infrared spectroscopy Fluid catalytic cracking Catalysis Hexane chemistry.chemical_compound Elementary reaction Physical chemistry Physical and Theoretical Chemistry ZSM-5
Zdroj:	Journal of Catalysis. 191:55-61
ISSN:	0021-9517
DOI:	10.1006/jcat.1999.2799
Popis:	An in situ diffuse reflectance infrared Fourier-transform spectroscopy (DRIFTS) study of n-hexane cracking over H-ZSM-5 and H-β zeolites has been carried out to elucidate the origin of first-order kinetics under bimolecular conditions. Contrary to an earlier proposal, the acidic protons are not extensively complexed with olefins during reaction. A simple qualitative kinetic model that consists of six elementary reactions has been used to rationalize the first-order rate law for n-hexane conversion with only a small fraction of the protons being complexed. Because of competing reactions, the olefin concentration, and, hence, the protonated-complex concentration, apparently becomes constant as a function of residence time and is independent of the hexane concentration.
Databáze:	OpenAIRE
Externí odkaz:	https://explore.openaire.eu/search/publication?articleId=doi_________::ff1e3ffac1f6df6374fab1a4ba59b274 https://doi.org/10.1006/jcat.1999.2799 Zobrazit plný text záznamu Full Text from ScienceDirect