| The gas hydrate, an important clatherate compound.Along with its development,the gas hydrate theory obtains rich. At present people already started to apply the gashydrate in many chemical industry areas. The gas hydrate has many application, inwhich natural gas storage is representatively. The natural gas take one kind of cleanrenewable energy, the traditional storage and transport way is insufficiency. NaturalGas Hydrate storage method (NGH) take continuously the most promising way, whichattracted scholar’s widespread attention. NGH carried on in nanometer space (WNG)overcome the former shortcoming, WNG enhanced the hydrate production speed,improve the speed of charge/discharge process. Uses this way, under10MPa theuptake of methane reach150V/V(STP）at2oC, reduced about half pressure comparewith CNG, saved the cost. In present work，through analyzed the condition of methanehydrate in the porous material, we established the optimal pore size for WNG is1.6nm-3nm. Based on the result, many different method for material preparation wereattempted，finally the method which use water activated in pore was found beensuitable。By this method, the suitable material was obtain for WNG named WAC-4with surface area3456m2/g, and pore volume(1.6nm-3nm)0.97ml/g. The maximmethane uptake on wet WAC-4reach64%, the chargeable quantity of methane reach202V/V(STP) at10MPa.The separation of N2, CH4is always considered as a most difficult problem. Withthe strengthen of exploitation of coal bed methane and shale gas, the new efficienttechnology for N2/CH4separation is necessary. N2/CH4separation via gas hydrate innano-space is a neo attempt. In the article by add THF solution to the pore ofWAC-4, both gas hydrate formation pressures reduced, causes it possible to combinegas hydrate separation with the PSA craft. The result indicated, in THF solutions, themethane hydrate formation pressure in pore drop arrives0.35MPa, the nitrogenhydrate formation pressure reduces to1.5MPa, base on the obvious difference of twoformation pressure, methane concentration experiment via PSA craft were carried on.Under the different pressure the feed gas can enrich from56.5%to75%. Innano-space, the scale of hydrate cystal formed in the pore is much more small, onlyseveral cells, once hydrate cavities formed, the nitrogen and methane may both enterin the cage. Ethylene can form gas hydrate at its critical temperature, it have the more uniqueapplication such as supercritical gas hydrate extraction. In present work, ethylenehydrate formation behavior in nano-space were studied and discovered the uniquehydrate formation behavior. On the porous material, the ethylene hydrate formaitonprocess possible can divide into two steps, the first step the ethylene molecule entersin the L cage of hydrate crystal, the second step, the ethylene molecule fill into S cage,when pressure is enough. Pore size of material has an important influence on ethylenehydrate formation behavior. Along with the pore size increase, the phenomenon oftwo step formation becomes fuzzy, finally vanished.CO2a major greenhouse gas, which contribute to global warming. It’ssequestration method is always an important topic include buried in seabed.Submarine sediments are made of naturally porous materials that are very similar toporous silicates. Simulates submarine environment, CO2hydrate formation behavioron several types of silicon-gels were studied. The results indicate the pore size hasvery impormtant effect on CO2hydrate formation. When the pore size is7nm orgreater, such as in SG-C, the CO2hydrate formation is difficult since the impetus ofpore space for hydrate formation disappears. |
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