Physical property measurements on CO2 clathrate hydrates. Review of crystallography, hydration number, and mechanical properties

Experimental studies on the physical properties of CO2 clathrate hydrate are summarized. They are useful for the feasibility study of CO2 sequestration into deep seawater. Crystallographic structure analyses and CO2 molecule contents in clathrate cages are necessary to estimate the density of CO2 clathrate hydrates. Mechanical properties of the CO2 hydrate film formed at the boundary between liquid CO2 and water are also important for study of CO2 deposition on the deep sea floor. In order to show the recent activities in this field and to clarify the remaining problems, this review also includes some studies on clathrate hydrates other than CO2 clathrate hydrate.