Surfactant Effects on Crystal Growth Dynamics and Crystal Morphology of Methane Hydrate Formed at Gas/Liquid Interface

Hiroaki Hayama, Makoto Mitarai, Hiroyuki Mori, Jonathan Verrett, Phillip Servio, Ryo Ohmura

Research output: Contribution to journalArticle

24 Citations (Scopus)

Abstract

This paper presents visual observations aiming to clarify the underlying physics of surfactant effects on clathrate hydrate crystal growth at the interface between methane gas and water with surfactant. Sodium dodecyl sulfate (SDS), which is commonly used in industrial processes, was used in this study. Various SDS mass fractions from 0 to wSDS = 100 ppm with a step of size 10 ppm were examined, where wSDS represents the mass fraction of SDS aqueous solution. The crystal growth behavior and the crystal morphology of the methane hydrate at the interface varied depending on surfactant concentration and ΔTsub. In systems with wSDS ≤ 20 ppm, the nucleation occurred on the droplet surface (gas/liquid interface), then grew laterally, and finally covered the whole droplet surface. On the contrary, at wSDS ≥ 30 ppm, the droplet shape was not maintained and enhanced hydrate crystal growth was observed compared to those systems with wSDS ≤ 20 ppm. Individual hydrate crystals at wSDS = 20 ppm were observed to be smaller than those in a pure water system at a given ΔTsub, which is ascribed to the enhanced hydrate nucleation by the addition of SDS.

Original languageEnglish
Pages (from-to)6084-6088
Number of pages5
JournalCrystal Growth and Design
Volume16
Issue number10
DOIs
Publication statusPublished - 2016 Oct 5

    Fingerprint

ASJC Scopus subject areas

  • Chemistry(all)
  • Materials Science(all)
  • Condensed Matter Physics

Cite this