管状复合炭膜的制备及气体分离性能  

Preparation of tubular composite carbon membrane for gas separation

作　　者：刘颖[1] 王同华[1] 李琳[1] 赵选英[1] 宋学凯[1] 

机构地区：[1]大连理工大学化工学院材料化工系精细化工国家重点实验室,炭素材料实验室,膜科学技术研究开发中心,大连116012

出　　处：《膜科学与技术》2010年第3期50-54,共5页Membrane Science and Technology

基　　金：国家自然科学基金(20776024);重点基金(20836006)

摘　　要：以商用PMDA-ODA型聚酰胺酸为涂膜液,采用浸渍涂膜法制备管状复合炭膜,考察支撑体的孔径尺寸、涂膜液浓度以及加入添加剂对所制备复合炭膜的气体分离性能的影响;并利用热重分析及扫描电镜考察所制备炭膜的热分解行为和复合效果.结果表明,与混煤支撑体相比,烟煤支撑体所制备的管状复合炭膜表现出更好的气体分离性能;随着涂膜液浓度的增加,气体的渗透速率呈先下降后上升的趋势,选择性则先增大后减小;添加表面活性剂不仅改善了涂膜液与支撑体表面的复合效果,减少了涂膜次数,同时提高了炭膜的气体渗透能力;在最佳制膜工艺条件下,H2、O2、CO2、N2的渗透速率分别为176.3×10-10、16.97×10-10、15.57×10-10、1.79×10-10mol/(m2.s.Pa),H2/N2、O2/N2、CO2/N2的选择性为100.7,10,9.34.The PAA-based composite carbon membranes were prepared by coating the PMDA-ODA polyamic acid solution on the coal-based membrane supports. The effects of different pore size of supports, concentration of the coating solution and addition of surfactant on the gas separation performance of composite carbon membranes were investigated. TG and SEM were employed to analyze the pyrolysis behavior and surface morphology of the composite carbon membranes. Results indicate that gas separation performance of composite carbon membranes from bituminous coal support is superior to the composite carbon membranes from mixed coal support. With the increase of coating solution＇s concentration, the gas permeation rates of composite carbon membranes are enhanced and the selectivities firstly rise and then reduce. The addition of surfactant not only improves the combination between the support and top film, but also reduces the coating times and enhances the gas permeation rates of composite carbon membranes. Under the optimum conditions for preparing composite carbon membranes, the permeation rates of H2,O2, CO2, N2 are 176.3×10^ -1, 16. 97 × 10^-10, 15. 57 ×10^-10, 1. 79 × 10^-10 mol/（m^2 · s · Pa）, the selectivities of H2/N2, O2/N2,CO2/N2 are 100. 7,10,9.34, respectively.

关 键 词：复合炭膜 聚酰亚胺 气体分离 

分 类 号：TQ028.8[化学工程]