Clathrate hydrates: recent advances on CH₄ and CO₂ hydrates, and possible new frontiers

Abstract

Gas hydrates continue to attract enormous attention throughout the energy industry, as both a hindrance in conventional production and a substantial unconventional resource. Scientists continue to be fascinated by the hydrates’ ability of sequestering large amounts of hydrophobic gases, unusual thermal transport properties and unique molecular structures. Technologically, clathrate hydrates promise advantages in applications as diverse as carbon sequestration and water desalination. The communities interested in hydrates span traditional academic disciplines, including earth science, physical chemistry and petroleum engineering. The studies on this field are equally diverse, including field expeditions to attempt the production of natural gas from hydrate deposits accumulated naturally on the seafloor, to lab-scale studies to exchange CO₂ for CH₄ in hydrates; from theoretical studies to understand the stability of hydrates depending on the guest molecules, to molecular simulations probing nucleation mechanisms. This review highlights a few fundamental questions, with focus on knowledge gaps representing some of the barriers that must be addressed to enable growth in the practical applications of hydrate technology, including natural gas storage, water desalination, CO₂ – CH₄ exchange in hydrate deposits and prevention of hydrate plugs in conventional energy transportation.

GRAPHICAL ABSTRACT

KEYWORDS:

• Gas storage
• nucleation
• anti-agglomerants
• promoters
• molecular simulations

Acknowledgments

This work was supported, in part, by the EPSRC, via grant number EP/N007123/1. The Author is grateful to Prof. Zach Aman of the University of Western Australia, for providing critical feedback for an early version of this review, and to the members of his research group for frequent stimulating discussions, and in particular to Dr Anh Phan for critically editing an early version of this manuscript.

This article is dedicated to Prof. Peter T. Cummings of Vanderbilt University, whose vision on the ability of molecular simulations to interpret, understand and eventually guide experimental explorations has been transformative, and has been extremely influential at the early crucial stages of the author’s career.

Disclosure statement

No potential conflict of interest was reported by the author.

Additional information

Funding

This work was supported by Engineering and Physical Sciences Research Council [grant number EP/N007123/1].