STRUCTURE H HYDRATE KINETICS STUDIED BY NMR SPECTROSCOPY

摘要

The knowledge on thermodynamics and kinetics of gas hydrates is important to further explore, develop and establish the technology for the safe and economic design of hydrate-based processes. They provide the information on hydrate formation conditions and reaction rates at which the phase transformation occurs. Fortunately thermodynamic studies are well established and hydrate phase equilibrium data and prediction software are readily available. However the study of hydrate kinetics, especially on structure H (sH) hydrate is very limited, sH hydrate has unique properties because two guest molecules of different sizes are required and it has the largest simple cage among all known hydrate structures. Hence, larger molecules like methylcyclohexane can fit into the cavity and smaller molecules may have multiple occupy in the large cage. The addition of a large molecule as a guest substance (LMGS) also stabilizes the crystal and reduces the equilibrium pressure. This is seen as an attractive opportunity and valid potential for gas storage application via gas hydrates.