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Title: Performance Projection of a High-Temperature CO 2 Transport Membrane Reactor for Combined CO 2 Capture and Methane-to-Ethylene Conversion

Direct conversion of methane into ethylene through the oxidative coupling of methane (OCM) is a technically important reaction. However, conventional co-fed fixed-bed OCM reactors still face serious challenges in conversion and selectivity. In this paper, we apply a finite element model to simulate OCM reaction in a plug-flow CO2/O2transport membrane (CTM) reactor with a directly captured CO2and O2mixture as a soft oxidizer. The CTM is made of three phases: molten carbonate, 20% Sm-doped CeO2, and LiNiO2. The membrane parameters are first validated by CO2/O2flux data obtained from CTM experiments. The OCM reaction is then simulated along the length of tubular plug-flow reactors filled with a La2O3-CaO-modified CeO2catalyst bed, while a mixture of CO2/O2is gradually added through the wall of the tubular membrane. A 12-step OCM kinetic mechanism is considered in the model for the catalyst bed and validated by data obtained from a co-fed fixed-bed reactor. The modeled results indicate a much-improved OCM performance by membrane reactor in terms of C2-yield and CH4conversion rate over the state-of-the-art, co-fed, fixed-bed reactor. The model further reveals that improved performance is fundamentally rooted in the gradual methane conversion with CO2/O2offered by the plug-flow membrane reactor.

 
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Award ID(s):
1924095
PAR ID:
10366755
Author(s) / Creator(s):
; ; ;
Publisher / Repository:
The Electrochemical Society
Date Published:
Journal Name:
Journal of The Electrochemical Society
Volume:
169
Issue:
5
ISSN:
0013-4651
Page Range / eLocation ID:
Article No. 053501
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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