Year: 2025
Type: article
Abstract: Reaction–diffusion coupling across the catalyst pore, grain, pellet, and reactor bed has been studied using a particle‐resolved transient microkinetic model applied to temperature‐programmed desorption and step‐response studies of methanol and dimethyl ether conversion over ZSM‐5 catalysts, respectively. An evolution of desorption across scales is provided. Five models (coverage, anomalous diffusion, mass transfer, fixed site‐interconversion, and dynamic site‐interconversion) are investigated to describe the 44‐min induction period in the first step‐response cycle and the 95% reduction in subsequent step‐response cycles. The reduction is due to dynamic autocatalytic interconversion across three active site‐ensembles. The first active site‐ensemble retains the kinetic function of the first step response cycle while the second and third active site‐ensembles adopt a new kinetic function mediated by surface methoxy species and adsorbed water. The dynamic site‐interconversion mechanism reduces the induction period, increases the reaction efficiency, and describes the formation of primary olefins.
Source: AIChE Journal
DOI: 10.1002/aic.18865
Author: Toyin Omojola
Institution: University of Bath
Language: English
Subfield: Inorganic Chemistry
Field: Chemistry
Domain: Physical Sciences
Open Access status: hybrid
Estimated APC paid: $4,940
Award: G6314138351
OpenAlex ID: W4409526276