Bifunctional Na–Ru on gamma-alumina for CO2 capture from air and conversion to CH4: impact of the regeneration method and support on monolithic contactors

Abstract

Dual functional materials (DFMs) have the potential to improve the process of CO₂ capture and subsequent conversion to fuel. Materials consisting of Na and Ru supported on alumina have been investigated for cyclic direct CO₂ air capture and conversion to CH₄. We have studied the regeneration conditions, specifically the target temperature and gas composition (inert or hydrogen-containing gas) during heating. The effect of air humidity and Na loading on the effectiveness of CO₂ capture has also been assessed. Finally, the DFMs have been successfully implemented as structured contactors with a low pressure drop, which is an unavoidable requirement for practical application.

Keywords: Dual functional materials; Direct air CO₂ capture; Methanation; Monoliths.