磁性有机-无机杂化分子印迹功能材料的制备及其调控MBR膜污染的机理

Membrane fouling, the major problem of flux decline and cost increasing, has severely hindered the wider application of membrane bioreactors (MBRs). Mitigating membrane fouling is quite challenging in MBR applications. This proposal aims to alleviate membrane fouling in MBRs with a novel method of magnetic molecularly imprinted polymers (MMIPs). Based on systematic analysis as well as precise identification of the major chemical components of membrane foulants, single-/multi- templated MMIPs will be prepared by combination of sol-gel, functional modification, surface molecular imprinting, and organic-inorganic hybrid methods, and will be incorporated into MBRs to significantly alleviate membrane fouling with the assistance of specific absorption properties of MMIPs and magnetic bio-effect. A membrane fouling model will be established based on the characteristics of sludge mixtures. In combination of the microbial diversity and multi-omics analyses, the mechanism of magnetite mitigating membrane fouling will be systematically and comprehensively illustrated from the perspectives of physical and chemical properties, species compositions, functional genes, metabolic pathways, and genetic regulation. This proposal is an extended investigation of magnetite mitigating membrane fouling, and also a frontier research field in the recognition of biological macromolecules via molecularly imprinting technology. The proposed research will serve as theoretical foundation and technical support for the further development of this technology.

由膜污染导致的膜通量降低、运行成本增加等问题，严重限制了膜生物反应器（MBR）的推广，至今仍是MBR研究与应用中的热点和难点。本项目拟针对MBR应用中“膜污染”这一行业难题，解析和识别主要膜污染组分，结合溶胶凝胶法、功能化修饰、表面分子印迹、有机-无机杂化等方法制备可特异性识别膜污染组分的单模板、多模板磁性有机-无机杂化分子印迹功能材料，在保持磁生物效应的前提下，提升特异性吸附效应，从而有效延缓膜污染进程。基于污泥混合液特性构建膜污染模型，结合微生物多样性和多组学分析，从理化特性、物种组成、功能基因、代谢途径、遗传调控机制等角度全面系统地揭示磁致效应调控MBR膜污染的机制。本项目是磁活性污泥法调控MBR膜污染在纵深方向的延伸和拓展，也是分子印迹技术应用到生物大分子识别方面的前沿研究领域，具有广阔的应用前景和理论价值。

本项目针对MBR应用中“膜污染”这一行业难题，在解析和识别主要膜污染组分基础上，选取多糖、蛋白质等主要的膜污染物质作为模版分子，结合溶胶凝胶法、功能化修饰、表面分子印迹、有机-无机杂化等方法制备可特异性识别膜污染组分的单模板、双模版、多模板磁性有机-无机杂化分子印迹功能材料（MMIPs），并通过构建3组MBR系统对比研究了MMIPs在MBR膜污染控制方面的应用特性和调控机理。研究发现：相对空白对照组（C-MBR），投加了MMIPs的MBR系统（M-MBR）污染物去除效果略有提升，但反应器中膜污染物质多糖的浓度可降低28%以上，蛋白质的浓度降低45%以上，相应地，膜污染速率（以ΔR30）从C-MBR的1.78×10^11/（m·d）降低到0.60×10^11/（m·d）；基于污泥混合液特性构建的膜污染模型显示，MMIPs的引入提升了磁致吸附效应和生物效应，有效延缓了膜污染；结合微生物多样性和功能基因预测分析发现，MMIPs的引入改变了MBR系统的微生物群落分布与代谢活动，最终影响了膜污染进程。本项目的研究成果将进一步完善和丰富磁活性污泥法调控MBR膜污染的技术体系和内容，可为该技术的进一步完善和推广应用提供理论依据和技术支撑。