Storage capacity of hydrogen in tetrahydrothiophene and furan clathrate hydrates

The storage capacity of hydrogen in the tetrahydrothiophene and furan hydrates was investigated by means of pressure–volume–temperature measurement. The hydrogen–absorption rate of tetrahydrothiophene and furan hydrates is much larger than that of tetrahydrofuran hydrate in spite of same crystal structure (structure-II). The storage amount of hydrogen at 275.1 K is about 1.2 mol (hydrogen)/mol (tetrahydrothiophene or furan hydrate) (∼0.6 mass%) at 41.5 MPa, which is coincident with that of tetrahydrofuran hydrate.