Unveiling the potential of CO₂ hydrates in porous media: A review on kinetic modelling, molecular dynamics simulations, and machine learning

Hydrate-based CO₂ sequestration in geological sediments is a potential technique that ensures storing CO₂ in large volumes providing huge CO₂ storage capacity. Numerous experimental studies report CO₂ hydrate formation kinetics in sediments; however, there is limited focus on hydrate-based kinetic modelling in porous media. This review aims to elucidate the molecular mechanisms that govern the formation kinetics of CO₂ hydrates in porous media in the presence of various additives. This review summarizes modelling studies on CO₂ hydrate formation, growth, and decomposition kinetics in porous media. This manuscript also provides detailed literature on molecular dynamic (MD) simulation studies of CO₂ hydrate formation kinetics in porous sediment addressing the key gaps. Moreover, it briefly introduces the machine-learning approaches for storing CO₂ as hydrate in porous sediment and their potential applications. The overall findings suggest that the level of modelling and simulation success of CO₂ hydrate formation in porous media has been achieved. However, the variations in the performance of the proposed models are influenced by the particle size, type of porous material, additive concentration, pressure, and temperature. Moreover, more research work is needed to develop effective models that could describe the kinetic behaviour of CO₂ hydrate growth and decomposition behaviour in porous sediments with additives.