Deactivation Kinetics of ZSM‐5 by Coke in Ethanol‐to‐Hydrocarbons Process

Abstract

Conversion of ethanol to hydrocarbons by porous zeolite ZSM‐5 is a sustainable alternative compared to crude oil, gas or coal conversion. A quantification and description of micro‐ and macroscopic deactivation kinetics with basic transport and reactor models reveals deeper insight into the dynamics of coking and product formation at varying contact time. A new first order deactivation model helps to separate linear deactivation and autocatalytic acceleration of catalyst decay. A deeper look into product formation reveals a change in selectivity during initiation and deactivation phase from bigger build‐up C5+ to smaller cracking products C3 after formation of coke precursors, which does not coincide with site‐loss and reduction of contact time alone. Thereby, deactivation and switching selectivity in the hydrocarbon pool concept become more deterministic, which paves the way to more selective ethanol conversion processes.