CO2 methanation with high-loading mesoporous Ni/SiO2 catalysts: Toward high specific activity and new mechanistic insights

Zhao, Yingrui;Girelli, Valentina;Ersen, Ovidiu;Debecker, Damien
(2023) Journal of Catalysis — Vol. 426, p. 283-293 (2023)

Files

ZhaoDebecker2023-postprint.pdf
  • Open Access
  • Adobe PDF
  • 1.41 MB

Details

Authors
  • Zhao, YingruiUCLouvain
    Author
  • Girelli, Valentina
    Author
  • Ersen, Ovidiu
    Author
  • Author
Abstract
In the power-to-gas scenario, surplus renewable electricity is stored in the form of methane, by reacting green hydrogen with waste CO2 through the Sabatier reaction. Low-cost catalysts that feature a high activity at low temperature are needed. We disclose the sol–gel preparation of high-loading mesoporous Ni/SiO2 catalysts. (HR)-TEM, XRD, N2 physisorption, and H2 chemisorption show that small Ni particles (<5 nm) are obtained, even at loading up to 38 wt%. The best catalyst reached a specific activity of 10.2 µmolCH4.g−1.s−1 at 250 °C (TOF = 0.0155 s−1; almost 3 times higher than a reference catalyst prepared by impregnation). Being based on inert silica, these catalysts are ideal model materials to elucidate the reaction mechanism on nickel. Combining CO2-TPD, in-situ CO2-DRIFTS, and TPSR with DFT calculations, we show that CO2 methanation follows mostly the RWGS + CO-hydrogenation and the formate pathways, the former being dominant at low temperature.
Affiliations

Citations

Zhao, Y., Girelli, V., Ersen, O., & Debecker, D. (2023). CO2 methanation with high-loading mesoporous Ni/SiO2 catalysts: Toward high specific activity and new mechanistic insights. Journal of Catalysis, 426, 283-293. https://doi.org/10.1016/j.jcat.2023.07.021 (Original work published 2023)