Development of Anti-biofouling Nanocomposite Polypropylene Fibers for Membrane Feed Spacers

CBET-0754387 Escobar开发用于膜进料间隔物的抗生物污染纳米复合聚丙烯纤维膜技术为满足日益严格的饮用水生产监管要求提供了巨大的希望。虽然其他技术可以实现类似的处理目标，但膜技术具有显著的优势。纳滤（NF）和反渗透（RO）膜已经使替代的水回收（即，微咸水和海水）和废水再利用的可能解决方案，以解决全球传统水源日益短缺的问题。在处理传统水源中实施NF和RO工艺可以提供稳定的去除水平，从而消除对离子交换树脂或颗粒活性炭再生的需要。此外，反渗透还可以通过海水和苦沃茨的脱盐来满足未来的饮用水需求。虽然NF和RO膜通常不用于消毒，但它们为去除病毒和细菌提供了额外的屏障，这对于间接饮用水和废水再利用至关重要。然而，对膜技术未来的乐观看法必须得到缓和，因为认识到仍有待解决的技术和成本问题。在这些问题中，被排斥的化学品和微生物对膜的污染继续需要相当大的关注。该项目的重点是微生物结垢或生物结垢，其是微生物在膜表面上和存在于封套之间的进料间隔物上的积累（即螺旋缠绕元件，其中膜折叠在连接到中心管的聚丙烯间隔物上）。生物污染预防领域的大多数研究和开发都集中在给水的预处理、改进的清洁溶液、清洁程序和抗污染膜上。本计画的目的是研制一种负载铜或银离子的抗生物污损聚丙烯（PP）纤维。这些PP纤维然后将用于制造RO螺旋缠绕元件的进料间隔件。铜和银离子是有效的消毒剂，并且通常被电解地或作为金属盐添加到水中以消毒水。使用抗生物污染进料间隔件的优点将是降低与化学品添加/储存相关的成本。智力优势：本文提出的新奇是将金属亲和配体共价结合到PP纤维上，所述PP纤维可以充有铜或银离子，以允许金属缓慢释放到膜系统中的给水中，用于生物污垢控制。选择固定化金属亲和色谱（IMAC）系统是因为其易于官能化并且能够通过修饰初始金属亲和配体来控制铜/银结合的程度。这里提出的假设是，PP纤维可以用对铜/银特异性的金属亲和配体纳米结构化，以产生抗生物污染的膜进料间隔物。为了验证假设，该项目分为三个目标：1。目的A：功能化纳米复合PP纤维。2.目的B：测试纳米复合PP纤维的生物污损性能。3.目的C：确定纳米复合纤维对膜的影响。更广泛的影响：当施加驱动力时，膜能够根据物质的物理和化学性质分离物质，并且它们能够过滤以去除胶体、细胞和分子。与膜的使用相关的主要问题是污染。膜污染通过通量损失、压力增加和清洗频率对膜性能和成本产生不利影响。开发低污染的膜过程是？圣杯？膜的研究。拟议项目的成果将通过培训研究生和本科生、同行评审的出版物和会议发言以及教育代表性不足的年轻移民学生了解饮用水问题和处理等方式传播。

CBET-0754387EscobarDevelopment of Anti-biofouling Nanocomposite Polypropylene Fibers for Membrane Feed Spacers Membrane technologies offer great promise to meet increasingly stringent regulatory requirements for potable water production. While other technologies can achieve similar treatment objectives, membranes offer notable advantages. Nanofiltration (NF) and reverse osmosis (RO) membranes have made alternative water reclamation (i.e., brackish water and seawater) and wastewater reuse possible solutions to address the growing global scarcity of traditional water sources. Implementation of NF and RO processes in treating traditional water sources can provide a steady-state level of removal that eliminates the need for regeneration of ion exchange resins or granular activated carbon. Moreover, RO can help meet future potable water demands through desalination of seawater and brackish waters. Although NF and RO membranes are generally not intended for disinfection, they provide an additional barrier for virus and bacteria removal, which is essential for indirect potable, wastewater reuse. An optimistic view for the future of membrane technology must be tempered, however, by recognition of the technical and cost issues that remain to be addressed. Of these issues, the fouling of membranes by chemicals and microbes that are rejected continues to demand considerable attention. The focus of this project is microbial fouling, or biofouling, which is the accumulation of microorganisms onto the membrane surface and on the feed spacer as present between the envelopes (i.e. spiral wound elements, in which the membrane is folded over a polypropylene spacer attached to a center tube). Most of the research and development in the area of biofouling prevention has focused on pretreatment of the feed water, improved cleaning solutions, cleaning procedures, and fouling resistant membranes. The goal of this project is to develop anti-biofouling nanocomposite polypropylene (PP) fibers loaded with copper or silver ions. These PP fibers will then be used to make feed spacers for RO spiral wound elements. Copper and silver ions are effective disinfectants and, conventionally, have been added to the water electrolytically or as metal salts to disinfect water. The advantage of using anti-biofouling feed spacers would be to decrease costs associated with chemical additions/storage. Intellectual Merit: The novelty proposed here is to covalently bind metal affinity ligands to PP fibers that can be charged with copper or silver ions to allow for slow release of metals into the feedwater in membrane systems for biofouling control. The immobilized metal affinity chromatograph (IMAC) system was chosen because of ease of functionalization and ability to control the degree of copper/silver binding through modification of the initial metal affinity ligand. The hypothesis proposed here is that PP fibers can be nanostructured with metal affinity ligands specific to copper/silver to lead to biofouling resistant membrane feed spacers. To test the hypothesis, the project is divided into three objectives: 1. Objective A: Functionalize the nanocomposite PP fibers. 2. Objective B: Test the biofouling properties of the nanocomposite PP fibers. 3. Objective C: Determine the effects of the nanocomposite fibers on the membrane. Broader Impacts: Membranes are capable of separating species as a function of their physical and chemical properties when a driving force is applied, and they enable filtration for removal of colloids, cells and molecules. The major concern associated with the use of membranes is fouling. Membrane fouling adversely affects membrane performance and cost through loss in flux, increase in pressure, and cleaning frequency. Developing a membrane process with low fouling is the ?holy grail? of membrane research. The results of the proposed project will be disseminated through the training of graduate and undergraduate students, peer-reviewed publications and conference presentations, and the education of young underrepresented migrant students on drinking water problems and treatment.