耐有机溶剂高性能超薄复合纳滤膜的研制及其应用基础研究

Organic solvents are vastly used in chemical, pharmaceutical, fine chemical industry. Traditionally distillation is used to recovery organic solvents, during which high energy and solvent consumption is encountered, as well as serious environmental pollution. Organic solvent-resistant nanofiltration (SRNF) membrane process could achieve excellent separation of target product from organic solvent and the reuse of the organic solvent, which is an important green chemical technology to solve the problem of energy, resource and environmental issues, and has broad application prospects. Good separation performance and solvent-resistance is the key of SRNF membrane preparation. In this research, a kind of SRNF membrane with good resistance to swelling and high rejection rate is intended to be prepared and investigated through an in-depth study of the interfacial polymerization preparation method of SRNF membrane, and through embedment of carbon nanotubes, self-assembly and cross-linking method,. Meanwhile, an in-depth study is intended to be performed on the interaction between the structure and properties of the monomer structure, the membrane forming process and reaction condition of SRNF membrane, the surface characteristics of SRNF membrane, the interaction mechanism of organic solvent and membrane separation layer, as well as that of solute and membrane separation layer. We are intended to explore swelling mechanism and method of structure regulation and effective swelling-resistance of SRNF membrane, and to develop new preparation technology of SRNF membrane and to deepen the understanding of the forming regularity of SRNF membrane by interfacial polymerization method, and to explore the mechanism of SRNF membrane separation of organic solution, and to provide theoretical support for high performance SRNF membrane preparation and application.

化工、医药、精细化工中均大量用到有机溶剂，传统的蒸馏过程能耗较高，溶剂损耗大，并易造成严重环境污染。耐有机溶剂纳滤（SRNF）膜过程可实现目标产物与有机溶剂的分离，是解决能源、资源和环境问题的重要绿色化学工艺，应用前景广阔。良好的分离性能和耐溶剂性能是SRNF膜应用的关键。本项目拟通过深入研究界面聚合SRNF膜制备方法，并通过石墨烯嵌入、自组装和交联等方法，制备出具有良好耐溶涨性和截留率的SRNF膜，研究单体结构、成膜工艺以及反应条件与SRNF膜的结构与性能之间的规律，并通过先进分析测试手段分析SRNF膜的表面特性，深入研究有机溶剂与膜分离皮层、溶质与膜分离皮层之间的作用机理，探究膜溶涨机制和调控SRNF膜结构和耐溶涨的有效方法，形成SRNF膜制备新技术，深化对界面聚合法制备SRNF膜成膜规律的认识，并探索SRNF膜对有机溶液的分离机理，为高性能SRNF膜的制备和实际应用提供理论支撑。

耐有机溶剂纳滤（SRNF）过程是一种分离有机溶剂的绿色工艺，可解决有机溶剂的传统蒸馏分离过程中能耗较高，溶剂损耗大，环境污染严重等问题，在化工、医药等行业应用前景广阔。但因为目前没有国产化的SRNＦ膜，大大限制了SRNF技术的应用。.SRNF 膜过程应用的关键是SRNF膜。国内外常用的相转化法所制备的SRNF膜存在通量小的固有缺陷。近年来界面聚合法受到重视。如何增强皮层与基膜的作用，解决耐溶剂性，并进一步提高通量，是当前要解决的主要问题。.本项目从基膜的选择开始，深入研究了SRNF 膜制备和调控耐溶胀性的有效方法。构建了膜的截留率、通量与膜的微观孔径分布以及孔隙率之间的关系模型；系统地研究了基膜种类、水相单体（间苯二胺，含氟二胺单体）和油相单体（三元酰氯、四元酰氯）及其浓度、界面聚合反应、化学亚胺化、化学交联、溶剂活化等一系列条件对膜微观结构与宏观性能的调控作用，并进行了条件优化，制备出了整体交联聚酰亚胺SRNF 膜, 分离性能和耐溶剂性能优异；利用多巴胺的协同作用有效调控了皮层与支撑层之间的相互作用，进一步提高了膜的耐溶剂性；开发了基于PI超滤膜的交联聚酰胺SRNF膜；利用纳米材料（石墨烯、石墨烯量子点、金属有机骨架、共价有机骨架）的掺杂进一步调控了SRNF膜的微观结构和分离性能,开发出了具有良好耐溶涨性和截留率的混合基质SRNF膜。以上所制备的几种SRNF膜在80℃的强极性溶剂DMF中浸泡一周后，对RDB(479 Da)的截留率仍可以达到99%，乙醇的渗透率超过20L/(m2.h.MPa)，部分SRNF膜的乙醇渗透率可达80L/(m2.h.MPa)，远高于商品SRNF膜，综合性能也高于一般文献中的SRNF膜性能。.本研究工作为高性能SRNF 膜的制备和实际应用提供了很好的理论支撑，对于拓宽SRNF膜在有机溶剂体系的分离、溶剂回收等领域的应用范围，替代某些耗能大、污染重的传统工艺过程，实现技术革新和产业升级、节能降耗、减少环境污染等具有很好的理论指导作用。