Promotion Effect of Copper Nanowire-Doped SDS in Methane Hydrate Formation

To speed up the formation of methane hydrate, copper nanowires (CuNWs) doped with sodium dodecyl sulfate (SDS) were used as a promotor. Transmission electron microscopy (TEM) images and elemental analysis of copper, oxygen, and sulfur indicated that SDS was successfully doped on the surface of copper nanowires. Compared with the SDS solution, the average hydrate induction time required for CuNW-SDS was significantly shortened from 71.25 ± 22.41 to 12 ± 4.89 min due to the strong thermal conductivity of copper nanowires. When SDS was used, the hydrate growth rates were about 0.56 ± 0.25 mmol/min. For CuNW-SDS, the hydrate growth rate was increased to 1.04 ± 0.53 mmol/min, which indicated that CuNW-SDS with better dispersibility enhanced the hydrate growth rate over 86% compared to that of SDS. In addition, when CuNW-SDS was used as a promoter, there were more dense hydrates, fewer foams generated by dissociation, and excellent recycling performance in the process of methane hydrate formation and dissociation.