SBIR Phase II: Chemically Resistant Membranes for Water Purification

这个SBIR二期项目将开发突破性的聚合物膜，通过反渗透净化水。它将解决全球公认的清洁饮用水需求，这是由人口增长和城市化推动的，影响到生活在缺水土地上的数十亿人。来自不同地理位置和不同类型的水（如海水、工业废水、自来水回用水）的水中杂质不同，能够选择性去除不同杂质组合的分离膜将是解决这一世界性挑战的关键。在这个价值约50亿美元的市场中，该技术大大减少了成本高昂的清洗操作，并最大限度地减少了工厂的停机时间。工业和提高能源和操作效率将通过减少所需的预处理和增强的抗污染能力来实现，从而延长使用周期，提高膜在使用寿命期间的水通量。该SBIR二期项目将在多孔载体上生产厚度约为100纳米的由精确磺化聚砜聚合物组成的薄膜复合反渗透（RO）膜。这些新型膜将为水净化膜提供长期追求的革命，具有高抗氯消毒能力和防止生物污染的能力。他们还将首次有效地从混合盐成分中去除污染海水和微咸水的单价盐。磺化聚砜由于其固有的耐化学性，以前曾被考虑用于反渗透膜，但由于在高离子强度下的低盐截留率以及在混合盐给水中的低盐截留率，它们失败了。城市用水要求很高，其加工用水往往受到有毒产品（硼和砷部分、碳氢化合物、全氟表面活性剂、生物膜）的污染，使得在技术上和经济上难以甚至不可能进行再利用。该项目通过精确磺化聚合物推进材料合成和材料加工。第二阶段将利用这些进步来优化膜涂层工艺，将其扩展到试验量，并测量对自来水回用、工业水净化、微咸地表水、地下水和高盐海水净化中发现的一系列杂质的抵抗力。该奖项反映了美国国家科学基金会的法定使命，并通过使用基金会的知识价值和更广泛的影响审查标准进行评估，被认为值得支持。

This SBIR Phase II project will develop breakthrough polymeric membranes to purify water by reverse osmosis. It will address the recognized global need for clean drinking water driven by increasing population and urbanization that affect billions of people living in water-stressed lands. The impurities in water from different geographical locations and different types of water (e.g., seawater, industrial wastewater, tap water reuse) differ, and separation membranes that can selectively remove different combinations of impurities will be critical to addressing this world challenge. The technology provides a means to greatly eliminate costly cleaning operations and minimize plant downtime in this ~$5 billion market. Industrial and Enhanced energy and operating efficiency will be achieved through reduced required pretreatment and enhanced fouling resistance, leading to extended use cycles and improved water flux over the lifetime of the membranes. This SBIR Phase II project will produce thin film composite reverse osmosis (RO) membranes comprised of precisely sulfonated polysulfone polymers in the ~100-nm thick range on a porous support. These novel membranes will provide a long sought after revolution in water purification membranes with their high resistance to chlorine for disinfection and ability to prevent biofouling. For the first time, they will also efficiently remove monovalent salts that contaminate seawater and brackish water from their mixed salt compositions. Sulfonated polysulfones have been considered previously for RO membranes due to their inherent chemical resistance, but they failed due to low salt rejection at high ionic strengths and their inferiority in salt rejections in mixed salt feedwater. Municipal water requirements are high and their process water is often contaminated with toxic products (boron and arsenic moieties, hydrocarbons, perfluorinated surfactants, biofilms), making reuse difficult to impossible technically and economically. This project advances material synthesis and material processing through precisely sulfonated polymers. Phase II will take advantage of these advances to optimize the membrane coating process, scale it to pilot quantities, and measure resistance to a range of impurities found in tap water reuse, industrial water purification, as well as in purification of brackish surface and groundwater and highly saline seawater.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.