Collaborative Research: Dry-Wet Phase Inversion Pathway of Graphene Oxide (GO)-Based Mixed-Matrix Membranes for Mineral Ions Separation by Membrane Distillation

合作研究：基于氧化石墨烯（GO）的混合基质膜用于膜蒸馏矿物离子分离的干湿相转化途径

• 批准号: 2002307
• 负责人: Lucy Mar Camacho
• 金额: $ 30万
• 依托单位: Texas A&M University-Kingsville
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 2020
• 资助国家: 美国
• 起止时间: 2020-08-01 至 2024-07-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=2002307&HistoricalAwards=false
• 关键词: Collaborative; Research; Dry; Wet; Phase

Increasing pollution and water scarcity have created the need to access and recover unconventional water sources. One such source is high-salinity produced water, which surfaces from underground during oil or gas production. Produced water has an excess concentration of minerals and does not meet the regulatory standards of acceptable quality for drinking water. However, by removing these undesirable constituents, the produced water can be reused for agricultural applications such as irrigation, livestock watering, and aquaculture. Therefore, identifying a process to desalinate produced water is of great societal importance. Reverse osmosis is a pressure-driven membrane process used to desalinate water containing relatively low mineral concentrations, such as groundwater. The mineral concentrations of produced water are sufficiently high that reverse osmosis is unsuitable for desalination. Membrane distillation is a promising alternative technology capable of separating minerals from high-salinity water due to its unique thermal-membrane characteristics. Graphene oxide-based membranes, with their efficient antifouling properties, are expected to enhance the membrane distillation process. Graphene oxide-based membranes are fabricated using a state-of-the-art method called phase inversion. Phase inversion produces these membranes by integrating graphene oxide directly into the polymeric materials. This project sets out to develop a detailed fundamental and mechanistic understanding of the role that graphene oxide plays in a novel dry-wet phase inversion synthesis to produce membranes for membrane distillation. This project will also combine research and education activities to train a new generation of experts in the versatile area of membrane technology, particularly as applied to water treatment.Membrane technology for water desalination and treatment of produced water has the potential to fundamentally alter the way society views water reuse. Augmenting water treatment capacity will allow rural, arid, and isolated regions with limited access to water, to have portable and reliable membrane systems for treating water. Advancing promising membrane separation processes for desalination, such as membrane distillation, requires access to fundamental knowledge of functional materials and structure-property relationship to engineer effective membranes. Membrane distillation is an energy-efficient alternative to multi-stage flash and multi-effect distillation processes and can be configured to concentrate brines. However, application of membrane distillation at scale is limited by the lack of suitable membranes exhibiting high permeate flux, water recovery, and resistance to scaling. The goal of this project is to establish and understand the dry-wet phase inversion membrane development approach to overcome these limitations in utility for produced water purification. Graphene oxide is a versatile anti-fouling nanomaterial that will be used in the synthesis of mixed-matrix membranes with properties specific to application in membrane distillation. Three research objectives are defined to provide fundamental insights into the dry-wet phase inversion process. In the first objective, the investigators will establish the role of graphene oxide sheet pH on pore formation and hydrophobic properties and determine the mechanism of dispersion of graphene oxide. The second objective examines ion retention on dry-wet phase inversion graphene oxide-based membranes during membrane distillation. And the third objective focuses on characterizing of the chemical, thermal, and mechanical stability of the dry-wet phase inversion graphene oxide-based membranes. Together, this knowledge will form a foundation for advancing membrane distillation for high-salinity water purification.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.

污染和缺水的日益增加已经使需要进入和恢复非常规的水源。这样的来源是高含量产生的水，在石油或天然气生产过程中，它们从地下浮出水面。生产的水具有过量的矿物质，并且不符合饮用水可接受质量的调节标准。但是，通过去除这些不良成分，可以将生产的水重复用于农业应用，例如灌溉，牲畜浇水和水产养殖。因此，确定淡化水的过程至关重要。反渗透是一种压力驱动的膜过程，用于淡化含有较低矿物浓度（例如地下水）的水。产生的水的矿物质浓度足够高，因此反渗透不适合脱盐。膜蒸馏是一种有前途的替代技术，能够由于其独特的热膜特性而将矿物质与高含水区分开。氧化石墨烯基膜及其有效的防染色特性有望增强膜蒸馏过程。基于氧化石墨烯的膜是使用称为相位反转的最先进方法制造的。相位反转通过将氧化石墨烯直接整合到聚合物材料中来产生这些膜。该项目旨在对石墨烯氧化物在新型的干湿相反转合成中的作用产生详细的基本和机械理解，以产生用于膜蒸馏的膜。该项目还将结合研究和教育活动，以培训膜技术多功能领域的新一代专家，尤其是应用于水处理。用于水的脱盐和处理水的膜技术有可能从根本上改变社会对水再利用的看法。增强水处理能力将使农村，干旱和孤立的区域有限获取水，可以具有便携式可靠的膜系统来处理水。促进有前途的膜分离过程（例如膜蒸馏），需要访问功能材料的基本知识以及与工程师有效膜的结构 - 性关系。膜蒸馏是多阶段闪光和多效蒸馏过程的节能替代品，可以配置为浓缩盐水。然而，膜蒸馏的应用限制受到缺乏表现出高渗透通量，水回收和对缩放性的耐药性的合适膜的限制。该项目的目的是建立和理解干湿期反转膜的开发方法，以克服这些效用的限制，以实现产生的水净化。氧化石墨烯是一种多功能的抗死纳米材料，将用于合成具有特异性在膜蒸馏中施用的特性的混合矩阵膜的合成。定义了三个研究目标，以提供对干燥阶段反转过程的基本见解。在第一个目标中，研究人员将确定氧化石墨烯片pH值在孔形成和疏水性能上的作用，并确定氧化石墨烯的分散机理。第二个客观检查在膜蒸馏过程中基于氧化石墨烯的氧化石墨烯的离子保留率。第三个目标着重于表征干湿相位石墨烯基膜的化学，热和机械稳定性。该知识将共同构成促进膜蒸馏以进行高含水净化的基础。该奖项反映了NSF的法定任务，并被认为是值得通过基金会的知识分子优点和更广泛的影响评估标准通过评估来支持的。