A Review of the Effect of Porous Media on Gas Hydrate Formation

Abstract

Most gas hydrates on the earth are in sediments and permafrost areas, and porous media are often used industrially as additives to improve gas hydrate formation. For further understanding its exploration and exploitation under natural conditions and its application in industry, it is necessary to study the effect of porous media on hydrate formation. The results show that the stacked porous media affects the phase equilibrium of hydrate formation depending on the competition water activity and large specific surface areas, while integrated porous media, such as metal foam, can transfer the hydration heat rapidly and moderate the hydrate phase equilibrium. A supersaturated metal–organic framework is able to significantly improve gas storage performance and can be used as a new material to promote hydrate formation. However, the critical particle size should be studied further for approaching the best promotion effect. In addition, together with the kinetic accelerators, porous media has a synergistic effect on gas hydrate formation. The carboxyl and hydroxyl groups on the surface of porous media can stabilize hydrate crystals through hydrogen bonding. However, the hydroxyl radicals on the silica surface inhibit the combination of CH 4 and free water, making the phase equilibrium conditions more demanding.

Comprehensive Review and Perspectives of CO2 Hydrate Storage in Subseafloor Saline Sediments: Formation, Stability, and Optimization Strategies

“…25 Conversely, coarser sediments might exhibit slower formation kinetics due to reduced interfacial contact between CO 2 and water molecules. 26,27 The presence and distribution of clay minerals within sediments also notably influence CO 2 hydrate pore-scale mechanisms�ranging from localized damage in low saturation to enhanced strength in highly saturated sediments.…”

Advances in Nanomaterials for Sustainable Gas Separation and Storage: Focus on Clathrate Hydrates

“…Consequently, hydrate technology utilizing porous media is better suited for applications in separation processes rather than for gas storage. Extensive research efforts have been dedicated to exploring the potential of porous media by employing diverse thermodynamic promoters and surfactant-type kinetic promoters. ,, Significant advancements have reported enhanced gas storage and faster formation rates. , Comprehensive investigations have examined the impact of textural properties, particle size, pore size, surface area, and wettability on the behavior of porous media. ,− Of particular interest in recent studies is the influence of wettability on gas hydrate formation kinetics and thermodynamic stability within porous media. , However, despite the significance of understanding the intricate mechanism underlying hydrate formation within confined interstitial pore spaces exhibiting distinct wettability characteristics, the current knowledge in this domain remains limited. Consequently, unveiling the nano-structural features governing hydrate formation in porous media with various wettability holds promising prospects for overcoming the limitations associated with the macroscopic performance of gas hydrates.…”

Dry Water as a Promoter for Gas Hydrate Formation: A Review

“…A wide range of porous media has been investigated, including metal-organic frameworks (MOFs) [37], silica sands [38][39][40], silica gels [39,41], superabsorbent polymers (SAP) [42][43][44], glass beads [45], clay [46], activated carbon [47,48], nanotubes [49,50], and biological porous materials [51]. If we disregard the impact of porous media on the phase equilibrium of gas hydrates, it is commonly believed that such media can provide a greater number of nucleation sites [52,53], increase the gas-liquid contact areas [54], thus promoting hydrate formation kinetics. The presence of porous media can also dissipate the latent heat of hydrate formation quickly [55] and improve the heat transfer efficiency.…”