| In the present study, the latest achievement and development in carbon membrane wasintroduced and the preparation ,properties ,gas separation mechanism and application of the hollow fiber carbon membrane were presented in detail in the thesis. The hollow fiber carbon membrane for gas separation which is prepared from α —cellulose precursor was described concretely. In addition, the change of chemical structure and pore structure of cellulose during carbonization was also investigated.In the preparation of hollow fiber carbon membrane from α —cellulose ,some process factors affected on gas separation ability of membrane such as the concentration and the species of the reagent, dipping times, draw rate and carbonization temperature were investigated and an appropriate process route and condition was confirmed. The results show that a α —cellulose-based hollow fiber membrane with crack-free and uniformity thickness were successfully prepared. The ideal separation factors of prepared carbon membrane at room temperature are 10.26 for O2/N2,26.54,46.93,15.63 and 1.69 for H2/N2, H2/CH4, CO2/N2, and H2/CO2 ,respectively, the permeation is 387GPU(1GPU=1 × 10-6 cm3/cm2.s.cmHg) for H2.It indicated that α —cellulose-based hollow fiber membrane shows high selectivity and permeability for gas separation, especially for the H2 and O2.The change of chemical structure and pore structure of α —cellulose-based hollow fiber membrane during carbonization was analyzed by TG, XRD, FTIR, and SEM. The results show that with the increase of carbonization temperature, crystal plane distance (d002) decreased to 0.3636nm, approaching to the standard value (0.3354) of graphite. There are three stages during pyrolysis of cellulose membrane. In the early stage, dehydration and solvent volatilization of cellulose membrane were obvious;three kinds of reactions such as cyclization, crosslinkling and cleavage occured in second stage. In the final stage, the cross-link degree increased deeply.
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