An experimental evaluation and molecular simulation of high temperature gas adsorption on nanoporous carbon

Abstract

A combination of experiments and molecular simulations has been used to further understand the contribution of gas adsorption to the carbon dioxide (CO2) selectivity of nanoporous carbon (NPC) membranes as a function of temperature and under mixed gas conditions. Whilst there have been various publications on the adsorption of gases onto carbon materials, this study aims to benchmark a simulation model with experimental results using pure gases. The simulation model is then used to predict mixed gas behaviour. These mixed gas results can be used in the assessment of NPC membranes as a suitable technology for both carbon dioxide separations from air-blown syngas and from natural gas. The gas adsorption experiments and molecular simulations have confirmed that CO2 is more readily adsorbed on nanoporous carbon than methane (CH4) and nitrogen (N2). Increasing the temperature reduces the extent of adsorption and the CO2 selectivity. However, the difference between the CO2 and N2 heats of adsorption is significant resulting in good CO2/N2 separation even at higher temperatures. © 2010 Elsevier Ltd. All rights reserved.