title: On the isosteric heat of adsorption of non-polar and polar fluids on highly graphitized carbon black.
abstract: Isosteric heat of adsorption is indispensable in probing the energetic behavior of interaction between adsorbate and solid, and it can shed insight into how molecules interact with a solid by studying the dependence of isosteric heat on loading. In this study, we illustrated how this can be used to explain the difference between adsorption of non-polar (and weakly polar) fluids and strong polar fluids on a highly graphitized carbon black, Carbopack F. This carbon black has a very small quantity of functional group, and interestingly we showed that no matter how small it is the analysis of the isosteric heat versus loading can identify its presence and how it affects the way polar molecules adsorb. We used argon and nitrogen as representatives of non-polar fluid and weakly polar fluid, and methanol and water for strong polar fluid. The pattern of the isosteric heat versus loading can be regarded as a fingerprint to determine the mechanism of adsorption for strong polar fluids, which is very distinct from that for non-polar fluids. This also allows us to estimate the interplay between the various interactions: fluid-fluid, fluid-basal plane and fluid-functional group.
authors.affiliation: Department of Advanced Materials, Institute of Technology and Science, The University of Tokushima, 2-1 Minamijosanjima, Tokushima 770-8506, Japan. Electronic address: horikawa@chem.tokushima-u.ac.jp.
authors.forename: Toshihide
authors.initials: T
authors.lastname: Horikawa
authors.affiliation: School of Chemical Engineering, The University of Queensland, St. Lucia, QLD 4072, Australia.
authors.forename: Yonghong
authors.initials: Y
authors.lastname: Zeng
authors.affiliation: School of Chemical Engineering, The University of Queensland, St. Lucia, QLD 4072, Australia.
authors.forename: D D
authors.initials: DD
authors.lastname: Do
authors.affiliation: Department of Advanced Materials, Institute of Technology and Science, The University of Tokushima, 2-1 Minamijosanjima, Tokushima 770-8506, Japan.
authors.forename: Ken-Ichiro
authors.initials: K
authors.lastname: Sotowa
authors.affiliation: Department of Advanced Materials, Institute of Technology and Science, The University of Tokushima, 2-1 Minamijosanjima, Tokushima 770-8506, Japan.
authors.forename: Jesús Rafael
authors.initials: JR
authors.lastname: Alcántara Avila
keywords: Graphitized carbon black; Isosteric heat of adsorption; Methanol adsorption; Water adsorption