open access

https://hdl.handle.net/2115/52371

Hydrogen absorption reaction kinetics and diffusion measurements in hydrogen clathrate hydrate at high pressure

日本語

2013-03-31

Institute of Low Temperature Science, Hokkaido University

Low Temperature Science

71

181-185

Kinetics of hydrogen clathrate hydrate synthesis is essential for its expected application of hydrogen storage. Its conventional production scheme was by freezing promoter’s solution contacting with pressurized hydrogen gas; it then takes long time for crystal growth. We have established an alternative scheme to store hydrogen into the clathrate hydrate; when hydrogen-free clathrate hydrate powder was contacted with pressurized hydrogen gas, hydrogen was quickly absorbed into the hydrate medium. We observed the reaction rate of hydrogen absorption by nuclear magnetic resonance spectroscopy as a function of hydrogen pressure and temperature. In our experimental conditions of pressures up to 20 MPa, the storage into the clathrate hydrate was completed within 80 minutes. We found that stored hydrogen are still mobile within the clathrate hydrate crystals, indicating that hydrogen can be repeatedly stored and released by cycling the hydrogen gas pressure. The diffusion coefficient of hydrogen was measured using a pulsed field gradient. It gives very large value of ＞ 10-8cm2/s, which is consistent with the observed fast absorption reaction of hydrogen storage into the clathrate hydrate.

紀要論文

Version of Record

1880-7593