Journal of Catalysis [POMAM]

Abstract

The direct CO₂ conversion to liquid fuels by catalytic hydrogenation (CO₂-based Fischer-Tropsch synthesis, FTS), is a sustainable approach to reduce CO₂ emissions. This challenging reaction proceeds through tandem catalysis involving reverse water gas shift reaction to produce CO and subsequent traditional CO-FTS. Unmodified Co-based catalysts allow performing the reaction at low temperatures (2-P25 support by NaBH₄ reduction so as to introduce controlled amounts of promoters and oxygen vacancies. The modified and unmodified supports were used to prepare Co-based catalysts, which were evaluated for CO₂-based FTS at 220–250 °C and 20 bar. The promoted catalysts outperform the one prepared on commercial TiO₂ in terms of activity and selectivity towards C₅₊. Detailed characterizations of the catalysts were performed to decipher the role of promoters. We show that, besides improving CO₂ activation and limiting H₂ activation, the presence of alkali on the support allows a modulation of hydrogen spillover in the system. The best catalyst in terms of activity and selectivity is the one for which sodium is deposited in sufficient amount to modulate the hydrogen spillover, which allows an optimal surface C/H ratio on cobalt.

 

Reference

Modified Co/TiO₂ catalysts for CO₂ hydrogenation to fuels

Canio Scarfiello, Katerina Soulantica, Simon Cayez, Aurélien Durupt, Guillaume Viau, Nolwenn Le Breton, Athanassios K. Boudalis, Frédéric Meunier, Guillaume Clet, Mathias Barreau, Davide Salusso, Spiros Zafeiratos, Doan Pham Minh, and Philippe Serp

Journal of Catalysis, Accepted 8 November 2023 – DOI: https://doi.org/10.1016/j.jcat.2023.115202

Contact

Athanassios K. Boudalis (team POMAM), Institut de Chimie de Strasbourg (UMR 7177).