Promotion Effect of Carbon Nanotubes-Doped SDS on Methane Hydrate Formation

To achieve greater performance of a low concentration of sodium dodecyl sulfate (SDS) in methane hydrate formation, SDS solutions were doped with pristine carbon nanotubes (pCNTs) and the oxidized forms (OCNTs). With nanotubes as the predominant accelerant in the mixed promoters, the nucleation stage could be shorten efficiently due to the continuous Brownian motion of more nanoparticles. The mixed promoters exerted more pronounced influence on the methane hydrate growth rate compared to the pure SDS, with the OCNTs-SDS system performing slightly better owing to the high dispersion and stability of the OCNTs in the aqueous SDS solutions. Nevertheless, the promotion effects of highly concentrated pCNTs or OCNTs could be weakened possibly due to the aggregation of nanotubes.