Hydrate-based gas separation (HBGS) technology review: Status, challenges and way forward

Abstract

Gas hydrates are crystalline, non-stoichiometric compounds that have several pertinent applications. This review attempts to present the current status of hydrate based gas separation (HBGS), discusses about existing challenges and puts forth future directions of research. Several pertinent gas mixtures including fuel gas (CO₂/H₂), flue gas (CO₂/N₂), biogas (CH₄/CO₂) and other industrially relevant mixtures are considered with gas hydrate based studies for each of these mixtures are presented. Advantages of using HBGS for gas mixture separation over other existing gas separation techniques has been elaborated in this work. In addition, the different kinetic and thermodynamic promoters studied for HBGS, their effectiveness in enhancing the gas separation, various reactor designs employed, patents on hydrate based gas separation, cost economics and energy requirement for HBGS are accounted.