H[subscript 2]-assisted CO[subscript 2] thermochemical reduction on La[subscript 0.9]Ca[subscript 0.1]FeO[subscript 3-δ] membranes: a kinetics study
Name
submitted manuscript - final.pdf
Size
1.55 MB
Format
Adobe PDF
Checksum (MD5)
4e3ee2da9190f4443227e00b92a7925b
Author(s)
Wu, Xiaoyu
Ghoniem, Ahmed F
Date Issued
November 2017
Journal
ChemSusChem
Publisher
Wiley Blackwell
Citation
Wu, Xiao-Yu, and Ahmed F. Ghoniem. “H[subscript 2]-assisted CO[subscript 2] thermochemical reduction on La[subscript 0.9]Ca[subscript 0.1]FeO[subscript 3-δ] membranes: a kinetics study.” ChemSusChem (November 2017) © 2017 WILEY-VCH
Version
Author's final manuscript
Abstract
Kinetics data for CO2 thermochemical reduction in an isothermal membrane reactor is required to identify the rate-limiting steps. Here, we report a detailed reaction kinetics study on this process supported by an La0.9Ca0.1FeO3-δ (LCF-91) membrane. The dependence of CO2 reduction rate on various operating conditions is examined such as CO2 concentration on the feed side, fuel concentrations on the sweep side and temperatures. CO2 reduction rate is proportional to the oxygen flux across the membrane, and the measured maximum fluxes are 0.191 and 0.164 μmol cm-2 s-1 with 9.5% H2 and 11.6% CO on the sweep side at 990oC, respectively. Fuel is used to maintain the chemical potential gradient across the membrane and CO is used by construction to derive the surface reaction kinetics. This membrane also exhibits stable performances for 106 hours. A resistance-network model is developed to describe the oxygen transport process and the kinetics data are parameterized using the experimental values. The model shows a transition of the rate limiting step between the surface reactions on the feed side and the sweep side depending on the operating conditions.
MIT Department
Massachusetts Institute of Technology. Department of Mechanical Engineering
Terms of Use
Creative Commons Attribution-Noncommercial-Share Alike
Persistent DSpace Link
DOI of Published Version
https://doi.org/10.1002/cssc.201701372
