| 초록 |
Recently, there were many studies about structures of gas hydrate because gas hydrates have generated considerable interests on the feasibility for the industrial application and attempts are being made to solve the global warming problem, especially CO2. There were also several studies to investigate guest molecules of structure H hydrates including CH4, N2, and CO2. There is controversy on the fact that CO2 functions as a co-guest molecule to form a structure H hydrate. In this study, we examined the CO2 + N2 + Methylcyclopentane (MCP) hydrate systems in terms of two perspectives: the function of CO2 as a co-guest in sH hydrates, and the influence of enclathrated CO2 on structural transition. To investigate the effect of sH hydrate formation on the four-phase (Gas hydrate - Liquid water - Liquid MCP - Vapor) equilibria of the CO2 + N2 + MCP hydrates were compare with three-phase equilibria of CO2 + N2 hydrate. The structural transition were verified using Raman spectroscopy, X-ray diffractometry (XRD), and differential scanning calorimetry (DSC). From these results, it can be explained that CO2 functions as a co-guest of sH hydrate and structural transition of sH to sI occurs. |
