微生物燃料电池分离膜的膜间传质机理与分子结构设计研究

This project dedicates to studying the mass transfer mechanism of anions, cations, oxygen and representative metabolism substrates in the separator of a Microbial Fuel Cell (MFC) system firstly, and develop new type of polymeric membranes for separation subsequently, aiming at the fairly low ion conductivity, durability, anti-fouling resistance and so on for the commercial available membranes. Which will include: (1)Utilizing our previous developed membranes derived from aromatic polyimides, poly(arylene ether sulfone), and polyphenylenes for fuel cell applications, mass transfer mechanism of primary ions, oxygen and representative metabolism substrates inside the separator are to be studied by static state simulation combined with theoretical calculation by Materials Studio system and SSNMR analysis. (2)It focuses on the structure-property relationship of the developed membranes, including ion conductivity, selective permeability of ions, durability, anti-fouling resistance, anti-oxygen resistance and so on, and subsequently improve the performance by rational polymer structure design and modification methods such as compositing and cross-linking. It is anticipated that the execution of this project could develop novel kinds of anionic and cationic polymeric separation membranes and provide valuable theoretical reference to the exploration of high-performance MFC system and achieve its applications for wastewater treatment.

本项目针对微生物燃料电池（MFC）中分离膜电导率低、稳定性差、抗污能力不足等问题，拟开展溶液中阴/阳离子、氧及代谢基质在膜间的传递机制研究，并据此开发新型MFC用高分子分离膜。内容包括：（1）根据MFC与高分子电解质膜燃料电池在原理上的相似性，利用本项目组已开发的芳香族聚酰亚胺、聚醚砜及聚苯类电解质膜为分离膜，采用静态模拟并结合Materials-Studio计算及固体核磁等手段，研究MFC运行过程中膜间主要离子、氧及代谢基质的传递机制；（2）着重于与MFC应用相关的分离膜的性能研究，考察膜的电导率、离子选择透过性、稳定性、抗污性、阻氧性等性能与分子结构的关系，设计合理的高分子结构，并通过复合、交联等手段，进一步提高分离膜的性能。通过本项目的开展，制备出新型的MFC用高分子分离膜,同时为高性能MFC的设计及应用提供分离膜材料及分离膜设计方面的理论依据，并实现在废水处理中的应用。

本项目针对微生物燃料电池（MFC）用分离膜的特性及开发开展了研究。以磺化聚芳醚砜（SPAES）膜为主要研究对象，阐明了在MFC条件下离子的透过机理。在MFC中，离子在分离膜中的透过行为主要取决于离子或离子基团的性质，即水合半径越小，价态越低，透过率越大；膜的性质具有一定的影响但不是决定性影响。因此，在双室MFC运行过程中，必须保证具有较小水合离子半径离子浓度的平衡，否则容易造成离子透过分离膜，影响MFC的性能。开发了四类新型的阳离子交换膜及二类阴离子交换膜，阐明了膜结构与性能的关系。适度增加高分子主链的刚性、引入交联结构、侧链亲水结构、高分子间的复合等，可以有效提高高分子膜的水解稳定性和尺寸稳定性；引入多嵌段结构、侧链亲水结构、亲水基团的富集化，有利于提高膜的电导率水平。分离膜的性质对于MFC的运行性能具有较大的影响。高电导率膜材料有利于加快MFC的启动，同时能够有效降低MFC内阻并达到更大的最大输出功率。阳离子交换膜膜具有更好的抗污性能，磺化聚酰亚胺类离子交换膜具有更加的抗污性。本项目的开展，对于MFC用分离膜的开发及应用，以及MFC的应用及发展具有积极的意义。