| 초록 |
Sulfur hexafloride (SF6), one of the most powerful greenhouse gases, should be separated from emission sources to mitigate global warming. A hydrate-based separation method can be suggested as a novel process. In this study, thermodynamic, kinetic, and structural properties of SF6 hydrate were investigated for hydrate-based SF6 separation. Three-phase (H- Lw-V) equilibria of SF6 hydrate formed in various media such as bulk water, hollow silica, and porous silica gels were measured to determine hydrate stability regions. The types of reaction media had no significant effects on thermodynamic stability of SF6 hydrate, but affected formation kinetics and gas uptakes of SF6 hydrate. The amount of gas consumed during hydrate formation in bulk water was similar to that in porous silica gels, whereas the formation rate in porous silica gels was much faster than that in bulk water. SDS which is kinetic hydrate promoter was found to significantly accelerate SF6 hydrate formation. Furthermore, the crystal structure of SF6 hydrate was identified as sII through powder X-ray diffraction. The experimental results will be helpful to understand the feasibility of hydrate-based SF6 separation. |
