587 / 2019-03-20 22:56:57

Kinetics of gas hydrate precipitation and decomposition via X-ray and neutron diffraction

gas hydrates; kinetic studies; X-ray and neutron diffraction

全体主题 > High Pressure Physics and Materials Science

Gas hydrates, an ice-like inclusion compound belonging to the clathrate family, occur widely in the ocean floor and permafrost region. Estimates suggest that the amount of carbon stored in hydrates is about twice that of all other known carbonaceous energy sources, including natural gas, oil, and coal. Therefore, gas hydrates may have great potential. Despite extensive experimental work on structures, phase equilibrium, and kinetics of gas hydrate formation, the mechanisms that control the precipitation and decomposition of gas hydrates are still poorly understood.
The talk will introduce the recent progress in kinetics of gas hydrate precipitation and decomposition, which are closely related with exploitation. The kinetics of gas hydrate precipitation and decomposition have been experimentally determined via in-situ X-ray and neutron diffraction, Raman spectroscopy, and infrared spectroscopy analyses, and they depend greatly on many factors such as temperature, pressure, and chemical compositions of starting fluids. However, previous experimental results show a great discrepancy, which may be attributed to many factors, including apparatus, analytical methods and structures of gas hydrates. All these factors will be reviewed and suggestions will be proposed in order to yield more reliable kinetic data.