(374j) Application of Calcium Oxide-Based Bifunctional Catalytic Sorbent to Hydrogen Production

Global warming is a result of the continuous emission of carbon dioxide from the combustion of fossil fuels. Carbon capture and storage (CCS) is proposed as a mid-term solution for this global warming issue. However, nearly 80% of the total operating cost of CCS occurs in the carbon dioxide capture/separation step. Developing a cost-efficient carbon dioxide capture technology is necessary to commercialize the CCS process. Among various technologies for the carbon dioxide collection process, calcium-looping (CaL) technology that utilizes calcium oxide-based adsorbents has emerged as an effective way to capture carbon dioxide in high-temperature conditions. While calcium oxide-based adsorbents have a high theoretical carbon dioxide uptake capacity of 17.8 mol kg^-1, it significantly decreases as the adsorption/regeneration process repeats due to their low thermal stability. To solve this cyclic instability, it has been known that incorporating thermally stable and inert materials improve the structural stability of the calcium oxide-based adsorbents. This study developed bifunctional catalytic sorbents by adding nickel to calcium oxide-based adsorbents and applied them to the sorption-enhanced steam methane reforming (SE-SMR) reaction for high-purity hydrogen production. Carbon dioxide adsorption uptake and hydrogen production efficiency of bifunctional catalyst were measured.