The work deals with the optimization of methane hydrate storage in fixed-bed reactor systems made up of modified silica beads. Under transient conditions, rapid hydrate growth is achieved at 4 °C. Glass beads are modified via silanization and treated with peroxymonosulfuric acid. It is proven that the fixed-bed surface properties significantly determine the gas hydrate growth and final gas uptake and therefore determine the successful technical design of the system. The capillary pressure is calculated in each bed configuration and is set in relation to the overall gas uptake. A negative capillary pressure leads to a holdback of water in the fixed-bed system. A high water-to-hydrate conversion is obtained for an untreated fixed bed with a positive capillary pressure. In the presence of SDS, the capillary effects are negated by the kinetic promotion effects. An inhibiting behavior is observed when using hydrophilic beads after treatment with peroxymonosulfuric acid.

This work deals with the influences of surface‐active coatings made by silanization with an increasing hydrophobicity on methane hydrate formation in view of induction times, gas uptake, and rate of gas consumption. Hydrate formation was performed in a stirred pressure autoclave under stationary and transient conditions in presence of different coatings made from diverse silanes. With increasing carbon chain length of the silanes, promoting effects were observed while using stationary formation conditions.

Gas hydrates show great potential with regard to various technical applications, such as gas conditioning, separation and storage. Hence, there has been an increased interest in applied gas hydrate research worldwide in recent years. This paper describes the development of an energetically promising, highly attractive rapid gas hydrate production process that enables the instantaneous conditioning and storage of gases in the form of solid hydrates, as an alternative to costly established processes, such as, for example, cryogenic demethanization. In the first step of the investigations, three different reactor concepts for rapid hydrate formation were evaluated. It could be shown that coupled spraying with stirring provided the fastest hydrate formation and highest gas uptakes in the hydrate phase. In the second step, extensive experimental series were executed, using various different gas compositions on the example of synthetic natural gas mixtures containing methane, ethane and propane. Methane is eliminated from the gas phase and stored in gas hydrates. The experiments were conducted under moderate conditions (8 bar(g), 9–14 °C), using tetrahydrofuran as a thermodynamic promoter in a stoichiometric concentration of 5.56 mole%. High storage capacities, formation rates and separation efficiencies were achieved at moderate operation conditions supported by rough economic considerations, successfully showing the feasibility of this innovative concept. An adapted McCabe-Thiele diagram was created to approximately determine the necessary theoretical separation stage numbers for high purity gas separation requirements.

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