A Thermodynamic Investigation of Adsorbate- Adsorbate Interactions of Carbon Dioxide on Nanostructured Carbons

A thermodynamic study of carbon dioxide adsorption on a zeolite-templated carbon (ZTC), a superactivated carbon (MSC-30) and an activated carbon (CNS-201) was carried out at temperatures from 241 to 478 K and pressures up to 5.5 106 Pa. Excess adsorption isotherms were fitted with generalized Langmuir-type equations, allowing the isosteric heats of adsorption and adsorbed-phase heat capacities to be obtained as a function of absolute adsorption. On MSC-30, a superactivated carbon, the isosteric heat of carbon dioxide adsorption increases with occupancy from 19 to 21 kJ mol-1, before decreasing at high loading. This increase is attributed to attractive adsorbateadsorbate intermolecular interactions as evidenced by the slope and magnitude of the increase in isosteric heat and the adsorbed-phase heat capacities. An analysis of carbon dioxide adsorption on ZTC indicates a high degree of binding-site homogeneity. A generalized Law of Corresponding States analysis indicates lower carbon dioxide adsorption than expected. Separations: Materials, Devices and Processes AIChE Journal DOI 10.1002/aic.15996 This article has been accepted for publication and undergone full peer review but has not been through the copyediting, typesetting, pagination and proofreading process which may lead to differences between this version and the Version of Record. Please cite this article as doi: 10.1002/aic.15996 © 2017 American Institute of Chemical Engineers (AIChE) Received: Aug 20, 2016; Revised: Jan 09, 2017; Accepted: Oct 09, 2017 This article is protected by copyright. All rights reserved.