Document Type
Article
Abstract
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 /O2 transport membrane (CTM) reactor with a directly captured CO2 and O2 mixture 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 /O2 flux data obtained from CTM experiments. The OCM reaction is then simulated along the length of tubular plug-flow reactors filled with a La2 O3 -CaO-modified CeO2 catalyst bed, while a mixture of CO2 /O2 is 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 CH4 conversion 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 /O2 offered by the plug-flow membrane reactor.
Digital Object Identifier (DOI)
Publication Info
Published in Journal of the Electrochemical Society, Volume 169, 2022.
APA Citation
Li, X., Huang, K., Noah Van Dam, & Jin, X. (2022). Performance Projection of a High-Temperature CO2 Transport Membrane Reactor for Combined CO2 Capture and Methane-to-Ethylene Conversion. Journal of the Electrochemical Society, 169(5).https://doi.org/10.1149/1945-7111/ac6ae7