title: Preservation phenomena of methane hydrate in pore spaces.
abstract: Dissociation processes of methane hydrate synthesized with glass beads were investigated using powder X-ray diffraction and calorimetry. Methane hydrate formed with coarse glass beads dissociated quickly at 150-200 K; in this temperature range methane hydrate dissociates at atmospheric pressure. In contrast, methane hydrate formed with glass beads less than a few microns in size showed very high stability up to just below the melting point of ice, even though this temperature is well outside the zone of thermodynamic stability of the hydrate. The rate-determining steps for methane hydrate dissociation within pores are also discussed. The experimental results suggest that methane hydrate existing naturally within the pores of fine particles such as mud at low temperatures would be significantly more stable than expected thermodynamically.
authors.affiliation: New Energy Resources Research Center, Kitami Institute of Technology, Kitami 090-8507, Japan. hachi@mail.kitami-it.ac.jp
authors.forename: Akihiro
authors.initials: A
authors.lastname: Hachikubo
authors.forename: Satoshi
authors.initials: S
authors.lastname: Takeya
authors.forename: Evgeny
authors.initials: E
authors.lastname: Chuvilin
authors.forename: Vladimir
authors.initials: V
authors.lastname: Istomin
mesh_terms: D002151:Calorimetry; D005898:Glass / Q000737:chemistry; D008697:Methane / Q000138:chemical synthesis / Q000737:chemistry*; D016062:Porosity; D033362:Powder Diffraction; D013696:Temperature; D014867:Water / Q000737:chemistry*
chemical_list: D014867:Water; D008697:Methane