CAREER: Membrane Processes for DBP Precursor Control: Effects of Colloid Stability and Membrane Surface Chemistry on Flux and Rejection

9984709 Kilduff合成聚合物膜在水处理中的使用在全球范围内不断增加，特别是用于去除消毒副产物（DBP）前体以及病原体和病毒。 微孔材料易受有机大分子和其他胶体的污染，并且这种污染通常控制了市政和工业应用中膜过程的效率、可靠性和成本。 本研究的目标是：（1）了解膜过滤系统中有机大分子与其他天然有机和无机胶体之间的相互作用，以及胶体稳定性如何影响膜过程的性能;（2）了解膜通量和截留率如何与膜表面化学相关，并确定紫外光改性的功效，以生产更耐污染的过滤膜。 将需要分馏和表征，以确定非均质环境胶体混合物组分的组成和反应性。 混合物的分离将根据尺寸（使用过滤）和化学官能度（使用吸附色谱法和溶剂沉淀）进行。 将评估单独的有机物分离物和胶体混合物对膜性能（污染、排斥和清洁）的影响。 混合物将包括有机物质部分和亚微米无机胶体（粘土、二氧化硅和氧化铁）。 结垢将与胶体的稳定性和污垢层的形态，使用原子力和共聚焦显微镜。 减轻结垢影响的策略将侧重于定制表面化学，以减少有机分子和胶体的结合。 聚合物膜的表面将通过UV辐射、随后的单体接枝和随后的聚合来改性（使其更亲水）。将评价单体类型、反应时间和UV辐射强度的影响。 将通过扫描电子显微镜、电子光谱学、接触角、衰减全反射红外光谱学，原子力显微镜和污垢的潜力，在实验室规模的测试细胞。教育计划围绕一个新的膜过程课程，学生将学习不仅是过程的基础知识，但也如何污垢可以导致处理系统表现出时间的发展中心-相关性能，以及如何将准确的参数估计纳入设计过程，以提高工艺可靠性。***

9984709 Kilduff The use of synthetic polymer membranes in water treatment is increasing worldwide, especially for the removal of disinfection by-product (DBP) precursors and of pathogenic organisms and viruses. The microporous materials are vulnerable to fouling by organic macromolecules and other colloids and this fouling often contols the efficiency, reliability and costs of membrane processes in municipal and industrial applications. The goals of this research are to: (1) understand the interactions between organic macromolecules and other natural organic and inorganic colloids in membrane filtration systems and how colloid stability influences the performance of membrane processes and (2) understand how membrane flux and rejection are related to membrane surface chemistry and identify the efficacy of UV photomodification to produce filtration membranes more resistant to fouling. Fractionation and characterization will be required to identify the composition and reactivity of components of heterogeneous environmental colloid mixtures. Separation of mixtures will be done on the basis of size, using filtration, and chemical functionality, using adsorption chromatography and solvent precipitation. The effects of individual organic matter isolates and of colloid mixtures on membrane performance (fouling, rejection and cleaning) will be evaluated. Mixtures will include organic matter fractions and sub-micron inorganic colloids (clays, silica and iron oxides). Fouling will be related to colloid stability and fouling layer morphology using atomic force and confocal microscopy. Strategies to mitigate fouling effects will focus on tailoring surface chemistry to reduce the binding of organic molecules and colloids. The surfaces of polymeric membranes will be modified (made more hydrophilic) by UV radiation followed by monomer grafting and subsequent polymerization. Effects of monomer type, reaction time and UV radiation intensity will be evaluated. As-received and fouled membranes will be characterized by scanning electron microscopy, electron spectroscopy, contact angle, attenuated total reflection infrared spectroscopy, atomic force microscopy and fouling potential in bench-scale test cells.The education plan centers around the development of a new Membrane Processes course from which students will learn not only process fundamentals but also how fouling can cause treatment systems to exhibit time-dependent performance, and how to incorporate accurate parameter estimation into the design process to improve process reliability. ***