Effect of Eco-Friendly Cyclodextrin on the Kinetics of Mixed Methane-Tetrahydrofuran Hydrate Formation

Use of environmentally friendly additives to promote methane hydrate formation is an active area of research for gas storage via solidified natural gas (SNG) technology. The key advantages of SNG technology include a high degree of safety and a compact mode of natural gas storage in comparison to conventional methods of NG storage. In this paper, we evaluate the effect of beta-cyclodextrin as a kinetic promoter for mixed methanetetrahydrofuran hydrate formation. beta-Cyclodextrin is an eco-friendly cyclic oligosaccharide containing seven glucose monomers that form a ring structure. The concentration of beta-cyclodextrin was varied under different hydrate forming conditions (temperature and pressure), and the formation kinetics along with the morphology of mixed hydrate formation were observed. It is found that beta-cyclodextrin served as an effective kinetic promoter for mixed methane-tetrahydrofuran hydrate formation at moderate pressure and temperatures in a simple unstirred reactor configuration. Further, no foam formation was observed during the hydrate dissociation that envisages an enhanced gas recovery and suitability of SNG technology for methane storage.