(222a) CO2 Capture By Adsorption Processes – Vacuum Swing Adsorption

Adsorption processes for CO2 capture from a variety of process streams have received increasing attention as the concern over climate change becomes more urgent. Work started around the world in earnest in the 1990's to understand the capabilities and obstacles to successful operation of adsorption processes for CO2 capture. Most of these efforts examined adsorbent development with much less attention devoted to process development. Over the last three years we have studied the CO2VSA (vacuum swing adsorption) process intensely using both our pilot scale VSA and our simulator. Through cycle design and economic evaluation, we have determined the operating region and performance window of the VSA process for 13X zeolite. Overall, a purity in excess of 95% is achievable with recoveries ranging from 70-80% depending on process parameters. In this study we report on how to exploit the adsorbent ? process synergy to produce a viable VSA design. Initial economic evaluation indicates promise for the technology although several obstacles still remain such as the presence of water and impurities in the stream and the large scale of operation. However, the great advances in materials development coupled to careful adaptation of process conditions means that there will be a role for adsorption processes in CO2 capture in the future.