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Updated: Aug 7, 2026
08:46
Methane Hydrate Crystallization on Sessile Water Droplets
Published on: May 26, 2021
Phase transitions in mixed gas hydrates: experimental observations versus calculated data
Judith M Schicks1, Rudolf Naumann, Jörg Erzinger
1GeoForschungsZentrum Potsdam, Section 4.2, Telegrafenberg, 14473 Potsdam, Germany. schick@gfz-postdam.de
The Journal of Physical Chemistry. B
|June 15, 2006
Summary
Multicomponent gas hydrates, primarily methane with ethane and propane, exhibit complex phase behavior. Unexpected transformations and coexistence of structure I and structure II hydrates were observed under specific experimental conditions.
Area of Science:
- Geochemistry
- Materials Science
- Chemical Engineering
Background:
- Gas hydrates are crystalline solids formed from water and small gas molecules.
- Multicomponent gas hydrate systems are relevant for energy storage and geological processes.
- Understanding phase behavior is crucial for predicting hydrate formation and stability.
Purpose of the Study:
- To investigate the phase behavior of methane-ethane-propane gas hydrate systems.
- To characterize hydrate structure, composition, and morphology.
- To observe and analyze unexpected hydrate transformation processes.
Main Methods:
- Experimental investigation of phase behavior under varying pressure and temperature.
- Microscopic observations for crystal morphology.
- Raman spectroscopy for composition and structure analysis.
- X-ray diffraction for crystallographic structure determination.
Main Results:
- Hydrates formed below the three-phase line, with light and dark crystals observed.
- Light crystals contained occluded free gas; dark crystals were structure II (sII) without occluded gas.
- An unexpected transformation to a foamy solid occurred upon cooling, revealing a mixture of structure I (sI) and sII hydrates.
Conclusions:
- The study provides novel insights into the phase behavior of specific multicomponent gas hydrates.
- Visual and spectroscopic techniques revealed complex hydrate formation and transformation.
- Coexistence of sI and sII hydrate phases was demonstrated under investigated conditions.
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