Exeprimental Verification of Cyclopentane Hydrates with Guest Molecules for Potential Applications to Desalination and Gas Storage

Abstract

In this study, flue gas, consist of CO2 (10%) + N2 (90%) and CO2 (20%) + N2 (80%), was injected into initial sH hydrate, formed with 2,2-dimethylbutane (Neohexane, NH) and CH4 (99.95%) gas for CH4 recovery and CO2 sequestration. The four- phase (H-LW-LNH-V) equilibrium line shift after the replacement verified that flue gas was successfully replaced with the CH4 in the sH hydrates. The 13C NMR confirmed that the CH4-flue gas replacement reaction proceeded without structural transition and the CO2 molecules also occupied the cages of sH hydrates. Stability conditions and heat of dissociation values after the replacement were measured using a high pressure micro-differential scanning calorimeter (HP μ -DSC) to confirm the extent of the replacement. During the CH4 - flue gas replacement in sH hydrates, there was no significant heat flow change associated with the dissociation and formation of hydrates. This study revealed that the CH4 – flue gas replacement in sH hydrate could successfully proceed without structural transition and noticeable hydrate lattice destruction.