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Updated: Jul 17, 2026
08:01
A Microfluidic Approach for the Study of Ice and Clathrate Hydrate Crystallization
Published on: August 18, 2022
Phase relations and binary clathrate hydrate formation in the system H2-THF-H2O
Ross Anderson1, Antonin Chapoy, Bahman Tohidi
1Centre for Gas Hydrate Research, Institute of Petroleum Engineering, Heriot-Watt University, Edinburgh EH14 4AS, U.K.
Langmuir : the ACS Journal of Surfaces and Colloids
|February 9, 2007
Summary
This study investigates hydrogen-tetrahydrofuran (H2-THF) clathrate hydrates, confirming their structure and hydrogen content. Findings resolve debates, showing H2-THF hydrates contain approximately 1 mass % H2, contradicting previous higher estimates.
Area of Science:
- Materials Science
- Chemical Engineering
- Physical Chemistry
Background:
- Clathrate hydrates are crystalline solids trapping guest molecules.
- Hydrogen clathrate hydrates are of interest for gas storage.
- Previous studies reported conflicting hydrogen content in H2-THF hydrates.
Purpose of the Study:
- Determine equilibrium phase relations for the H2-THF-H2O system.
- Investigate the structure and hydrogen incorporation in H2-THF clathrate hydrates.
- Resolve controversy regarding the maximum hydrogen content in these hydrates.
Main Methods:
- Experimental determination of phase relations.
- Varying aqueous tetrahydrofuran (THF) concentration.
- Temperatures from 260 to 290 K and pressures up to 45 MPa.
- Direct compositional analyses of clathrate phases.
Main Results:
- Formation of cubic structure-II (CS-II) binary H2-THF clathrate hydrates.
- Stoichiometric THF-to-water ratio of 1:17.
- Incorporation of molecular hydrogen at elevated pressures.
- Full occupancy of large cages by THF and 80-90% filling of small cages by H2 at >30 MPa.
- Maximum H2 content confirmed at approximately 1 mass %.
Conclusions:
- Experimental data support the formation of H2-THF clathrate hydrates with specific structural and compositional characteristics.
- Findings confirm lower hydrogen content, resolving previous discrepancies in the literature.
- The study provides accurate data for understanding hydrogen storage in clathrate hydrates.
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