多孔材料改性聚醚嵌段酰胺复合膜分离油气研究  

Separation of oil vapor by polyether block amide composite membrane modified with porous materials

作　　者：王北福 蔡雨婷 徐荣 聂立宏 WANG Bei-fu;CAI Yu-ting;XU Rong;NIE Li-hong(College of Petrochemical Engineering and Environment,Zhejiang Ocean University,Zhoushan 316022,Zhejiang,China;College of naval architecture and maritime,Zhejiang Ocean University,Zhoushan 316022,Zhejiang,China)

机构地区：[1]浙江海洋大学石油化工与环境学院,浙江舟山316022 [2]浙江海洋大学船舶与海运学院,浙江舟山316022

出　　处：《安全与环境学报》2023年第4期1280-1287,共8页Journal of Safety and Environment

基　　金：浙江省基本公益研究计划项目(LGF20E040002,LGF19B070004)。

摘　　要：油气在空气中挥发到极限会发生剧烈爆炸,用膜分离技术回收有机气体可以降低危险发生概率。膜分离油气的能力主要受通量和分离系数影响。采用微孔材料Silicalite-1分子筛和介孔材料MCM-41分子筛分别对聚醚嵌段酰胺(PEBA)复合膜进行改性研究。结果显示:两种分子筛在改性PEBA复合膜时,功能层旋涂得相比未改性的更薄,从而产生更高的有机气体通量;分子筛增强了膜的疏水性,使有机气体更易吸附在膜表面。PEBA/MCM-41和PEBA/Silicalite-1改性膜都能有效地增强气体的渗透性和选择性,且低温有利于油气分离。加入介孔分子筛MCM-41的主要分离机理是Knudsen扩散,可使小分子油气的分离系数显著提高,相比未改性的膜可提高近16倍;加入微孔分子筛Silicalite-1的主要分离机理是溶解扩散,可使大分子的分离系数明显提高,相比未改性的膜大约提高6倍。In this study,polyether block amine(PEBA)composite membranes were modified with microporous molecular sieve Silicalite-1 or mesoporous molecular sieve MCM-41.To investigate the effect of porous molecular sieves on the modification of composite membranes,the separation membranes were characterized by scanning electron microscopy,water contact angle measurements,and infrared spectroscopy,and they were also tested separately for gas separation performance.The following general conclusions can be drawn.When microporous Silicalite-1 and mesoporous MCM-41 molecular sieves are used to modify PEBA composite membranes,the selective layer of the membrane becomes thinner,which improved the gas permeability.Silicalite-1 enhances the hydrophobicity of the membrane and effectively improves its selectivity towards organic vapor.And the modification of PEBA membranes by both molecular sieves is physical,without chemical reaction.Both PEBA/MCM-41 and PEBA/Silicalite-1 composite membranes can effectively separate oil vapor and show improved permeability and selectivity toward organic gas.Owing to the relatively large pores of MCM-41,the permeability of its corresponding membrane is slightly higher than that of the Silicalite-1 modified membrane.The influence of temperature on the membrane is that the permeability decreases as the temperature rises.Generally,the gas transport in the polymer matrix is mainly by dissolution diffusion,which is related to the ability of the gas molecules to penetrate the surface layer of the polymer.The addition of mesoporous molecular sieves increases the number of non-selective voids,and the transport mechanism then tends towards Knudsen diffusion.Therefore,PEBA/Silicalite-1 membranes are more effective in separating large molecules.Meanwhile,the addition of MCM-41 increases the small pores in the membrane matrix,which facilitated the passage of small molecules through the membrane.And less addition of larger pores makes the selectivity for large molecules increases by a lower degree.In addition,the

关 键 词：环境工程学 油气分离 MCM-41分子筛 Silicalite-1分子筛 有机-无机复合膜 

分 类 号：X701.7[环境科学与工程—环境工程]