Skip to main content

Hydrophobic Solvation of Gases (CO2, CH4, H2, Noble Gases) in Clay Interlayer Nanopores

Author(s): Gadikota, Greeshma; Dazas, Baptiste; Rother, Gernot; Cheshire, Michael C; Bourg, Ian C

To refer to this page use:
Abstract: In the past few years, experimental studies have shown that CO2 is roughly 5 times more soluble in water saturated clay interlayer water than in bulk liquid water. The fundamental basis of this selectivity remains unknown, as does its relevance to other gases. Here, we use molecular dynamics (MD) simulations and gravimetric adsorption experiments to determine the solubilities of CO2, CH4, H2, and noble gases in clay interlayer water. Our results confirm that clay minerals, despite their well-known hygroscopic nature, have a significant hydrophobic character at the atomistic scale. The affinity of dissolved gases for the clay surface shows significant variations related to the size and shape of the adsorbing molecules and the structuring of interfacial water by clay surfaces. Our results indicate that dissolved gases likely do not behave as inert tracers in fine-grained sedimentary rocks such as shale and mudstone, as routinely assumed in groundwater hydrology studies. Our results have implications for the fundamental science of hydrophobic adsorption, for the use of dissolved gases as tracers of fluid migration in the subsurface, and for low-carbon energy technologies that rely on fine-grained sedimentary rocks, such as carbon capture and storage, nuclear energy, and the transition from coal to natural gas.
Electronic Publication Date: 1-Nov-2017
Citation: Gadikota, Greeshma, Dazas, Baptiste, Rother, Gernot, Cheshire, Michael C, Bourg, Ian C. (2017). Hydrophobic Solvation of Gases (CO<sub>2</sub>, CH<sub>4</sub>, H<sub>2</sub>, Noble Gases) in Clay Interlayer Nanopores. The Journal of Physical Chemistry C, 121 (47), 26539 - 26550. doi:10.1021/acs.jpcc.7b09768
DOI: doi:10.1021/acs.jpcc.7b09768
ISSN: 1932-7447
EISSN: 1932-7455
Language: en
Type of Material: Journal Article
Journal/Proceeding Title: The Journal of Physical Chemistry C
Version: Final published version. This is an open access article.

Items in OAR@Princeton are protected by copyright, with all rights reserved, unless otherwise indicated.