Catalytic CO2 sorbents, materials that adsorb and pre-concentrate CO2 on the catalyst surface prior to subsequent conversion, are becoming important materials in CO2 capture and utilization. In this work, a prototypical CO2 methanation catalyst – Ru/Al2O3 – and a related catalytic sorbent – NaNO3/Ru/Al2O3 – are used for CO2 methanation in flowing hydrogen in a fixed bed reactor at temperatures ranging from 220 to 280 °C. Activation energies for the NaNO3/Ru/Al2O3 material are slightly higher than unpromoted Ru/Al2O3 catalysts, and the reaction orders vary more significantly. In situ IR spectroscopy and steady-state isotopic kinetic analysis (SSITKA) using in situ IR/MS spectroscopy show that bicarbonate and linear carbonyl species are the likely reaction intermediates over unpromoted Ru/Al2O3, while bidentate carbonate, formate and linear carbonyl species are among likely reaction intermediates over NaNO3/Ru/Al2O3. Rate laws consistent with the obtained experimental data are proposed after kinetic modeling of multiple plausible reaction pathways. In conclusion, results suggest that the pathway over the NaNO3/Ru/Al2O3 catalyst likely has an additional kinetically relevant irreversible step in the CO2 methanation reaction pathway.
Park, Sang Jae, et al. "CO<sub>2</sub> methanation reaction pathways over unpromoted and NaNO<sub>3</sub>-promoted Ru/Al<sub>2</sub>O<sub>3</sub> catalysts." Catalysis Science and Technology, vol. 12, no. 14, Jun. 2022. https://doi.org/10.1039/d2cy00515h
Park, Sang Jae, Wang, Xiang, Ball, Madelyn R., Proaño, Laura, Wu, Zili, & Jones, Christopher W. (2022). CO<sub>2</sub> methanation reaction pathways over unpromoted and NaNO<sub>3</sub>-promoted Ru/Al<sub>2</sub>O<sub>3</sub> catalysts. Catalysis Science and Technology, 12(14). https://doi.org/10.1039/d2cy00515h
Park, Sang Jae, Wang, Xiang, Ball, Madelyn R., et al., "CO<sub>2</sub> methanation reaction pathways over unpromoted and NaNO<sub>3</sub>-promoted Ru/Al<sub>2</sub>O<sub>3</sub> catalysts," Catalysis Science and Technology 12, no. 14 (2022), https://doi.org/10.1039/d2cy00515h
@article{osti_1885245,
author = {Park, Sang Jae and Wang, Xiang and Ball, Madelyn R. and Proaño, Laura and Wu, Zili and Jones, Christopher W.},
title = {CO<sub>2</sub> methanation reaction pathways over unpromoted and NaNO<sub>3</sub>-promoted Ru/Al<sub>2</sub>O<sub>3</sub> catalysts},
annote = {Catalytic CO2 sorbents, materials that adsorb and pre-concentrate CO2 on the catalyst surface prior to subsequent conversion, are becoming important materials in CO2 capture and utilization. In this work, a prototypical CO2 methanation catalyst – Ru/Al2O3 – and a related catalytic sorbent – NaNO3/Ru/Al2O3 – are used for CO2 methanation in flowing hydrogen in a fixed bed reactor at temperatures ranging from 220 to 280 °C. Activation energies for the NaNO3/Ru/Al2O3 material are slightly higher than unpromoted Ru/Al2O3 catalysts, and the reaction orders vary more significantly. In situ IR spectroscopy and steady-state isotopic kinetic analysis (SSITKA) using in situ IR/MS spectroscopy show that bicarbonate and linear carbonyl species are the likely reaction intermediates over unpromoted Ru/Al2O3, while bidentate carbonate, formate and linear carbonyl species are among likely reaction intermediates over NaNO3/Ru/Al2O3. Rate laws consistent with the obtained experimental data are proposed after kinetic modeling of multiple plausible reaction pathways. In conclusion, results suggest that the pathway over the NaNO3/Ru/Al2O3 catalyst likely has an additional kinetically relevant irreversible step in the CO2 methanation reaction pathway.},
doi = {10.1039/d2cy00515h},
url = {https://www.osti.gov/biblio/1885245},
journal = {Catalysis Science and Technology},
issn = {ISSN 2044-4753},
number = {14},
volume = {12},
place = {United States},
publisher = {Royal Society of Chemistry},
year = {2022},
month = {06}}
Oak Ridge National Laboratory (ORNL), Oak Ridge, TN (United States); Energy Frontier Research Center (EFRC) (United States). Center for Understanding and Control of Acid Gas-Induced Evolution of Materials for Energy (UNCAGE-ME)
Sponsoring Organization:
USDOE Office of Science (SC), Basic Energy Sciences (BES). Chemical Sciences, Geosciences & Biosciences Division; National Science Foundation (NSF)
Grant/Contract Number:
AC05-00OR22725; SC0012577
OSTI ID:
1885245
Alternate ID(s):
OSTI ID: 1872484
Journal Information:
Catalysis Science and Technology, Journal Name: Catalysis Science and Technology Journal Issue: 14 Vol. 12; ISSN 2044-4753