Rapid and repeatable methane storage in clathrate hydrates using gel-supported surfactant dry solution

Gel-supported surfactant dry solution (GDS) was prepared by mixing gelling agent, sodium dodecyl sulfate (SDS) solution, hydrophobic silica nanoparticles and air in a high speed blender. GDS has the merits of surfactant dry solution (DS) and gel-supported dry water (GDW). The stack of micron-sized GDS droplets provides abundant gas transport channels and large surface area for gas-liquid contacting. Each droplet is a micro system with active surface and gelling structure. Methane storage in clathrate hydrates using GDS was investigated in a stainless steel vessel without stirring under the condition of 5.0 MPa and 273.15 K. The results demonstrated that the dispersed GDS droplets could significantly enhance formation kinetics, storage capacity and storage repeatability of methane hydrate. In addition, GDS exhibited faster storage rate (4.5221 m(3) m(-3) min(-1)) and higher storage capacity (152.23 m(3) m(-3)) than GDW. Compared with SDS-DS, GDS has similar storage rate and better storage repeatability (by experiment of 9 cycles), but its storage repeatability slightly became poor and capacity decay occurred due to the agglomeration of droplets after these cycles of hydration/dissociation. (C) 2016 Published by Elsevier Ltd.