Methane hydrate efficient formation in a 3D-rGO/SDBS composite.

Abstract

The optimization of storage space and material composition can significantly improve the generation rate and storage capacity of methane hydrate, which is important for the industrial application of solidified natural gas (SNG) technology. In our report, the effects of the presence of SDBS (sodium dodecylbenzene sulfonate), GO (graphene oxide), 3D-rGO (3D-reduced graphene oxide) and 3D-rGO/SDBS (3D-reduced graphene oxide/sodium dodecylbenzene sulfonate) on the methane hydrate generation process are investigated. The results show that the heterogeneous effect on the solid-phase surface of 3D-rGO/SDBS and its interconnected three-dimensional (3D) structure can achieve rapid nucleation. In addition, the presence of 3D-rGO/SDBS can increase the dissolution and dispersion of gas in solution and further enhance the gas-liquid mass transfer, thus realizing efficient methane storage. The maximum methane storage capacity of 188 v/vw is obtained with 600 ppm of 3D-rGO/SDBS in water, reaching 87% of the theoretical maximum storage capacity. The addition of 3D-rGO/SDBS also significantly reduces the induction time and accelerates the formation rate of methane hydrate. This study reveals that 3D graphene materials have excellent kinetic promotion effects on methane hydrate formation, explores and enriches the hydrate-promoting mechanism, and provides essential data and theoretical basis for the research of new promoters in the field of SNG technology.