Dual function materials for CO2 capture and conversion using renewable H2

Abstract

The accumulation of CO2 emissions in the atmosphere due to industrialization is being held responsible for climate change with increasing certainty by the scientific community. In order to prevent its further accumulation in the atmosphere, CO2 must be captured for storage or converted to useful products. Current materials and processes for CO2 capture are energy intensive. We report a feasibility study of dual function materials (DFM), which capture CO2 from an emission source and at the same temperature (320°C) in the same reactor convert it to synthetic natural gas, requiring no additional heat input. The DFM consists of Ru as methanation catalyst and nano dispersed CaO as CO2 adsorbent, both supported on a porous γ-Al2O3 carrier. A spillover process drives CO2 from the sorbent to the Ru sites where methanation occurs using stored H2 from excess renewable power. This approach utilizes flue gas sensible heat and eliminates the current energy intensive and corrosive capture and storage processes without having to transport captured CO2 or add external heat.