A Perspective on the Role of Gas Hydrates in Carbon Capture, Transport, and Sequestration.

Gas hydrate-based carbon capture, transport, and sequestration (GH-CCS) has emerged as a promising alternative for mitigating anthropogenic CO2 emissions. Gas hydrates selectively encapsulate CO2 within crystalline water frameworks under moderate pressure and temperature conditions, offering advantages such as solvent-free operation, high selectivity, and inherent stability for long-term storage. This review provides a comprehensive evaluation of GH-CCS across the entire process chain, including CO2 capture, transport, and sequestration. Recent advances in hydrate-based separation from fuel gas (CO2/H2) and flue gas (CO2/N2) streams are discussed, with emphasis on phase behavior, promoters, and reactor design. Developments in hydrate-based CO2 transport are examined, focusing on slurry transport, rheology, and flow assurance challenges. Sequestration strategies in marine sediments, geological formations, and permafrost regions are also reviewed, including CO2-CH4 exchange mechanisms. Key technical and economic challenges such as hydrate formation kinetics, energy requirements, scale-up feasibility, and long-term storage stability are critically assessed, and future research directions are outlined.