聚酰亚胺、聚砜、聚醚砜及其共混改性中空纤维膜用于醇/醚气相分离的研究

甲醇／ 甲基叔丁基醚的分离是目前具有实用意义的重要研究课题之一，采用气流吹扫式操作，研究了聚酰亚胺、不同结构的聚砜中空纤维膜在不同操作条件下，对甲醇／ 甲基叔丁基醚气相混合体系的分离性能，也研究共混改性对分离膜性能的影响。结果表明，各种材料的膜具有相近的分离行为，即随着气相中甲醇含量的增加，透过通量逐渐增大而分离系数逐渐减小，聚酰亚胺膜具有适中的透过通量，但具有很高的分离系数，在甲醇浓度低于２０ ％ 时，分离系数可达数千。采用聚醚砜共混改性的聚酰亚胺膜在未明显降低透过通量的条件下，使醇／ 醚分离系数大幅度提高，有很好的应用前景。

Studies of the Gas Phase Separation of Methanol MTBE Mixtures with Hollow Fiber Membranes Spun with the Polyimide, Polysulfone, and the Blends of Polyimide and Poly(ether sulfone)

The separation of methanol MTBE mixtures is one of the significant filds to practicality today. In this paper, the separation properties of hollow fiber membranes, which were made of polyimide, polyether sulfones and their blends,in the vapor permeation process of the methanol MTBE mixtures were studied.The effects of the operation conditions on the separation properties were discussed. The results show that the flux decreases and the separation coefficients increases with decreasing of methanol concentration in gas phase.The separation coefficients of the polyimide hollow fiber membranes for methanol MTBE mixtures are very high.When the methanol concentration is lower than 20 wt%, the separation coefficient of polyimide hollow fiber can come up to thousands,and it can be enhanced further by the blend modification.The application prospects is great.