132 / 2023-06-24 18:17:57

Rapid methane hydrate formation promoted by AgNP@rGO for energy storage

Methane hydrates, Nonsurfactant-based promoter, Nanofluid, Energy storage, 3D structure

Rapid methane hydrate formation promoted by AgNP@rGO for energy storage

Ming Yang^a*, Baoyong Zhang^a, Jingjing Nan<sup>a

a</sup> National Central Laboratory of Hydrocarbon Gas Transportation Pipeline Safety, Department of Safety Engineering, Heilongjiang University of Science and Technology, Harbin 150022, China

*Corresponding author: Ming Yang, E-mail:ymusth@126.com

*Tel.: +8618800428218.  Fax: +86-451-88036489.

Keywords: Methane hydrates, Nonsurfactant-based promoter, Nanofluid, Energy storage, 3D structure

To resolve long induction time, slow formation kinetics and limited hydrate storage capacity issues, some novel kinetic and thermodynamic promoters have be developed. Among which carbon-based materials have become one of the most attractive due to large specific surface area and pore structure. Herein, we described a facile synergetic strategy to generate a nonsurfactant-based composite kinetic promoter with 3D sandwich structure to realize the significant promotion towards hydrate production. Results on the introduction of silver nanoparticles (AgNP) onto the surface of reduced graphene oxide (rGO) nanosheets as a novel 3D sandwich structure promoter via in situ reduction method. The performance of AgNP@rGO on hydrate formation kinetics was evaluated. As a consequence, under the synergistic effect of Ag nanoparticles and rGO nanosheets, they not only could promote mass transfer but they could also contribute to heat transfer enhancement in the hydrate reaction. Moreover, rGO nanosheets with an optimal water ratio can provide excellent interfaces that enlarge the area of gas-liquid contact for hydrate nucleation and growth. The sandwich structure AgNP@rGO nanofluid have high specific surface areas, offering plenty of nucleation sites for hydrate formation. Then, the continuous movement of AgNP@rGO promoters helps to remove the heat generated during hydrate formation. Besides, the stable AgNP@rGO nanofluid has excellent recycling performance in repeated hydrate formation, which thus contributes to more economical hydrate production. These findings provide new perspective on the application of nanofluid composites on hydrate-based solidified natural gas technologies.