| Greenhouse gases have become a serious world problem. With the development of economy, the CO2 concentration in the atmosphere is increasing, which will have the potential to cause severe changes in the global climate and ecosystem. Accordingly, it is desirable to reduce CO2 emission into atmosphere. In a global content, among all the industries emitting CO2, fossil-fueled power plants generate the largest amount of CO2 emission and that accounts for about 30 percent of the total. Consequently, new energy-saving and effective technology to capture CO2 from the flue gases should be developed in present factory for CO2 emission reduction. It has scientific significance and broad application prospects in reducing the greenhouse effect and environmental protection.There are some obvious disadvantages of conventional CO2 separation technology. Whereas the new hydrate-based separation process has the advantages of high gas recovery, mild conditions, simple flowsheet, environmentally friendly。Yet its process is high energy-consuming and intermittent which is unfitable for industrial application. In order to enhance the sequestration of CO2, Hydrate membrane separation which combined hydrate with membrane separation has been proposed. Influencing factors of forming hydrate membrane and separation performance, such as materials and surface propertiy of the porous membrane, the pore size of ceramic tube, gas composition, pressure and temperature etc, were investigated using the self-established experimental apparatus of hydrate membrane separation for CO2 capture to get the best experimental parameters. The main results and conclusion obtained in this dissertation were as follows:(1) Hydrate membrane separation experiments were carried out by using of various porousα-Al2O3 ceramic membrane tube (mean pore size:3～6um,500nm,380nm,200nm), porous carbon membrane tube (mean pore size:116nm), ceramic membrane tube modified by silica (porous silica membrane). The results indicated that hydrate membrane were formed in the pores of porousα-Al2O3 ceramic membrane (mean pore size:380nm,200nm),carbon membrane,silica membrane, which enhanced the separation factors of CO2/N2. The best suitable materials to form hydrate membrane were carbon membrane and silica membrane, then was 380nm ceramic membrane. The separation factors were 1.78,1.25,1.4 and gas permeance were 0.1～1.00×10-8mol·(m2·s·Pa)-1,1.4-4.5×10-8mol·(m2·s·Pa)-1,0.3-1.6×10 -8mol·(m2·s·Pa-1 separately for 380nm ceramic membrane, carbon membrane and silica membrane.(2) Experiments carried in ceramic membrane showed that CO2/N2 mixture gas with more CO2 would be easier to form flawless hydrate membrane under condition of higher pressure, lower temperature and longer static time and with the addition of TBAB (5%wt) or memory water. Experiments carried in carbon membrane and silican oxide membrane also proved that higher pressure, lower temperature, longer static time would be more suitable for hydrate membrane formation.(3) Influencing factors of separation performance:As the reduction of pressure in permeance side, permeance enhanced, while separation factor increased firstly, then descended. It implied that there would be a best pressure in permeance side for separation. Experiments carried in ceramic membrane demonstrated that separation factor would increased if gas flux was reduced, and would decreased if TBAB(5%wt) was added.
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