Unveiling the promoting effect of V and Ce on Ru/TiO2 catalysts for CO2 methanation

Details

Supervisors

Debecker, Damien P. ; Hongmanorom, Plaifa

Faculty

Faculté des bioingénieurs

Degree label

Master [120] : bioingénieur en chimie et bioindustries, à finalité spécialisée

Abstract

enCO2 methanation represents a promising route for utilizing CO2 as a feedstock to mitigate climate change. However, this reaction still faces kinetic limitations, making catalytic development crucial. To advance in catalyst design, understanding the role of metal promoters is essential. In this study, the promotional effects of vanadium and cerium on Ru/TiO2 catalysts for CO2 methanation were systematically investigated. Ru-based catalysts supported on P25 and promoted with varying amounts of vanadium (Ru/y%V2O5-P25) or cerium (Ru/x%CeO2-P25) were prepared to assess the influence of these promoters on catalytic performance. In situ DRIFTS measurements revealed that CO2 methanation on Ru/P25, Ru/3%CeO2-P25 and Ru/12%V2O5-P25 followed the formate and the CO pathway. The formate pathway was identified as the promoted route, in which CO2 interacted with surface hydroxyl groups to produce adsorbed bicarbonates, the bicarbonates were then converted to formates, followed by the formation of CH4. The promotion effect was assigned to the increasing amount of hydroxyl groups formed upon reduction. Additionally, cerium was shown to enable CO2 activation at lower temperatures due to the presence of oxygen vacancies.