SusChEM: High Throughput Screening of Anti-fouling and Anti-bacterial Coating Films

CBET-1337065Eric M.V.加州大学洛杉矶分校围绕全球淡水供应减少的健康问题是众所周知的，新的生态、农业和地缘政治影响现在正在被认识到。甚至有人预测，到2025年，美国等发达国家将被视为“缺水”。目前，聚合物膜技术是从海水或废水等非传统来源生产清洁饮用水的最先进方法。给水通过高度选择性的塑料薄膜泵送，污染物被拒绝：然而，由于被拒绝的污染物积累在膜表面和/或膜孔内，膜很快就会被污染。大量的能量和水损失在膜清洗上，频繁的渗透反冲洗和周期性的苛刻化学清洗会降解膜聚合物，导致过早更换。该项目的目的是开发耐污染的膜，通过用能够排斥或使污染材料失活的化合物来修饰膜的表面，以减少与水处理膜相关的能源需求和运行成本。膜的表面改性已被证明，但大多数都需要外来的反应条件，反应时间长，和/或昂贵的试剂，限制了它们的商业应用。该项目团队最近开发了一种新型的表面修饰化学物质，将抗粘连和抗菌化合物共价连接到聚合物膜的表面。该反应是在室温和大气压下在水中进行的，同时使用廉价的试剂和环境友好的处理条件。初步结果表明，商业反渗透膜和超滤膜很容易被多种化合物改性。这些膜保持了它们的基本分离性能特征，但表面发生了巨大的变化。结果是，通过改变修饰化学和条件，我们可以调节细菌对反渗透膜的黏附。为了确定最佳的防污化合物性能，将合成几种化合物，并使用项目组先前开发的高通量筛选方案来筛选防污行为。这些化合物将具有不同的静电电荷、相对分子质量和抗菌功能。商用膜将使用新的表面化学物质进行改性，并对其生产率、污染物截留率、改善的耐污性和清洗简易性进行评估。该项目将开发用于大规模水处理的新型抗污染膜材料。通过对不同性质的膜表面进行改性，将确定最佳的表面性质，以帮助理解在水环境中导致表面污染和生物膜形成的机制。该项目的成果将为大规模生产防污染膜提供一种有效的方法，以减少将海水或废水转化为清洁、可用水所需的能源需求和运营成本。

CBET-1337065Eric M.V. HoekUniversity of California, Los AngelesThe health issues surrounding the diminishing supply of global freshwater are well known and new ecological, agricultural, and geopolitical implications are now being recognized. It is even predicted that developed nations such as the United States will be considered "water-stressed" by 2025. Currently, polymeric membrane technology is the state-of-the-art method to produce clean, potable water from unconventional sources such as seawater or wastewater. The feed water is pumped through the highly selective plastic films and pollutants are rejected: however, the membranes quickly foul due to accumulation of rejected pollutants on the membrane surface and/or within membrane pores. A significant amount of energy and water are lost to membrane cleaning with frequent permeate backwashes and periodically cleaning with harsh chemicals that degrade membrane polymers resulting in premature replacement. The aim of this project is to develop fouling-resistant membranes to reduce increased energy demand and operating costs associated with water treatment membranes by modifying the surface of the membranes with compounds that repel or deactivate fouling materials. Membrane surface modifications have been demonstrated in past, but most have required exotic reaction conditions, long reaction times, and/or expensive reagents that limited their commercial application. The project team recently developed a novel surface modification chemistry that covalently attaches anti-adhesion and anti-bacterial compounds to the surface of polymeric membranes. The reaction is performed in water at room temperature and atmospheric pressure while using inexpensive reagents and environmentally benign processing conditions. Preliminary results demonstrate that commercial RO and UF membranes are easily modified by a variety of compounds. The membranes retain their basic separation performance characteristics, but have dramatically altered surfaces. The result is that by altering modification chemistry and conditions we can modulate bacterial adhesion to RO membranes. To determine optimal anti-fouling compound properties, several compounds will be synthesized and screened for anti-fouling behavior using High-Throughput Screening protocols previously developed by the project team. The compounds will have varying electrostatic charge, molecular weight, and anti-bacterial functionality. Commercial membranes will be modified with the new surface chemistries and evaluated for their resultant productivity, pollutant rejection, improved fouling-resistance and ease of cleaning. This project will develop new anti-fouling membranes materials for large-scale water treatment. By modifying membrane surfaces with different properties, optimal surface properties will be ascertained to help understand the mechanisms that contribute to surface fouling and biofilm formation in aqueous environments. The result of this project will provide an effective way to produce anti-fouling membranes on a large scale to reduce energy demand and operating costs associated with converting seawater or wastewater into clean, usable water.