| Uncontrolled emission of CO2 from industrial sources has caused an increasing global problem of greenhouse effect and environment pollution. Membrane processes can be an alternative to energy demanding separation processes with the advantage of the low cost and friendly to the environment. Inorganic membranes, such as zeolite membrane and carbon membrane are gaining rapid attention in the industrial application of CO2 separation owing to their unique properties, such as thermal, mechanical, and chemical stability, good erosion resistance, and stability at high CO2 pressures.Both zeolite L and zeolite T have similar Si/Al ratio (3～4), therefore they both have the strong CO2 adsorption ability. Both membranes can be synthesized without the aid of the organic template, the manufacturing cost of the membrane can be reduced greatly. The microwave heating is becoming the popular method for the preparation of zeolite membrane in the recent years. The microwave heating can shorten the synthetic time effectively and the membrane prepared by microwave heating is thin and compact, so the gas permeation performance of the zeolite membrane has been improved greatly. More recently, the zeolite/carbon membrane as a kind of new membrane material has the good gas separation performance,In this dissertation, the zeolite L membrane and zeolite T membrane were prepared by conventional hydrothermal method and microwave hydrothermal method. The zeolite L/carbon composite membrane and zeolite T/carbon composite membrane were also prepared. The CO2/CH4 and CO2/N2 separation performance of these inorganic membranes were investigated in detail. The main results achieved in this work are as follows:The zeolite L membrane was prepared by microwave hydrothermal method onα-Al2O3 tubes. Microwave synthesis has the advantage of both rapid and uniform heating and effective control of crystal structure, so the gas permeation performance of the membrane prepared by microwave heating was better than the membrane prepared by conventional heating. The CO2 permeane was 7.96×10-7 mol·Pa-1·m-2·s-1,and CO2/CH4 and CO2/N2 ideal selectivities were 20.5 and 9.3 at 298K. In the equimolar mixture permeation experiments, the CO2/CH4 and CO2/N2 separation factors were 27.3 and 15.7 at 298K.The thin zeolite L/carbon nanocomposite membrane (about 3～4μm) was obtained on the porous alumina tube by incorporating nano-sized zeolite L (about 100nm) into polymeric precursor (polyfurfuryl alcohol (PFA)). At 298K, the single gas permeances of H2, CO2, N2 and CH4 through the composite membrane were about 1.0×10-7,5.72×10-8,2.8×10-9 and 1.6×10-9 mol·m-2·s-1·Pa-1, respectively. The CO2/CH4 and CO2/N2 separation factors in the equimolar mixture permeation experiments reached to 43.59 and 27.21, which were higher than the ideal selectivities of 35.75 and 20.43 in the single gas permeation experiments. The CO2 separation performance of the composite membrane with respect to Robeson trade-off line showed that CO2/CH4 separation performance exceeded Robeson's upper limit and CO2/N2 separation performance approached the Robeson's upper bound line. It can be concluded that the composite membrane provide one of promising candidates for separation of the industrial CO2/CH4 and CO2/N2 mixtures.The zeolite T membrane was prepared by microwave hydrothermal method onα-Al2O3 tube. In the pure gas permeation test, the CO2 permeane was 6.75×10-8 mol·Pa-1·m-2·s-1, and CO2/CH4 and CO2/N2 ideal selectivities were 115 and 45.9 at 298K. When the temperature increased to 423K, the CO2/CH4 and CO2/N2 ideal selectivities reached to 74 and 20. In the equimolar mixture permeation experiments, the CO2/CH4 and the CO2/N2 separation factors were 163 and 67 at 298K. When the temperature increased to 423K, the CO2/CH4 and CO2/N2 separation factors were still at the high values of 91 and 34. Compared to the zeolite membrane synthesized by other references, the zeolte T membrane prepared by microwave heating in this work was competitive to CO2 separation performance.The zeolite T/carbon composite membrane was obtained on the porous alumina tube by incorporating zeolite T particles (about 300nm) into PFA precursor. In the pure gas permeation test, the CO2 permeance was 8.31×10-9 mol·Pa-1·m-2·s-1, and the CO2/CH4 and CO2/N2 ideal selectivities were 97.3 and 51.6 at 298K. The CO2/CH4 and CO2/N2 ideal selectivities were 38.1 and 17.4 at 423K. In the equimolar mixture permeation experiments, CO2/CH4 and CO2/N2 separation factors reached to 121 and 53.8 at 298K. The CO2/CH4 and CO2/N2 separation factors were 40.3 and 19.2 at 423K. The CO2 separation performance of the composite membrane with respect to Robeson trade-off line showed that CO2/CH4 separation performance exceeded Robeson's upper limit and CO2/N2 separation performance approached the Robeson's upper bound line. It can be concluded that the zeolite T/carbon composite membrane had good CO2/CH4 and CO2/N2 selectivity, but the CO2 permeance should be improved.
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