Collaborative Research: ECO-CBET: Putting entropy to work: Leveraging the role of water organization in peptide binding events to selectively recover rare earths

合作研究：ECO-CBET：让熵发挥作用：利用水组织在肽结合事件中的作用来选择性回收稀土

• 批准号: 2133549
• 负责人: Christine Duval
• 金额: $ 84.88万
• 依托单位: Case Western Reserve University
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 2021
• 资助国家: 美国
• 起止时间: 2021-08-15 至 2025-07-31
• 项目状态: 未结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=2133549&HistoricalAwards=false
• 关键词: Collaborative; Research; ECO; CBET; Putting

Rare-earth elements are critical components in wind turbines, electric vehicles, and smart phones. The United States imports 100% of its rare earth elements from China, where they are mined and purified through time- and energy-intensive processes. The United States has great potential to recycle rare earth elements from waste streams such as coal industry waters, electronic wastes, and fertilizer mining wastes. This project, a collaboration between Case Western Reserve University, Clemson University, and Pennsylvania State University-University Park, will recover valuable rare earth elements (La, Ce, Nd, Pr) from phosphogypsum—a fertilizer mining waste mixed with radioactive impaired water. Currently, phosphogypsum is piped to open ditches or ponds and stored indefinitely as “stacks”. Today, an estimated more than 200 million tons of rare earth elements are trapped in unprocessed phosphogypsum waste in Florida alone. This source of rare earth elements is presently untapped due to challenges associated with radioactive species and the difficulty of separating the individual elements. Further, stack failures post a threat to the environment as phosphogypsum sites have caused over 200 million gallons of contaminated water to be released to Florida aquifers and surface waters since 1994. Thus, the vision for this project is to discover new separation mechanisms, materials, and processes to recover valuable resources (rare earth elements, fertilizers, clean water) from waste streams of the fertilizer industry, paving the way for a sustainable domestic supply of rare earth elements and a sustainable agriculture sector. Doing so will enable the recycling of an otherwise unusable waste stream and treat impaired waters that threaten local water supplies. Simultaneously, the next generation of engineers will be trained to tackle complex environmental engineering problems at the forefront of the food-energy-water nexus. Educational outreach programs will target the general public using the social media app TikTok and engage local high school students in research experiences and mentoring programs. In addition, interactive activities for K-12 outreach events focused on sustainability and water treatment will be developed.Traditional membrane separation mechanisms rely on differences in size and charge which are insufficient to purify individual rare earth elements due to their similar radii and identical formal charge. This project pursues a multistage separation process in which rare earth elements are 1) extracted from phosphogypsum by chemical digestion, 2) separated from anions and concentrated by electrodialysis, and 3) selectively separated using peptide-functionalized membranes. A key technical goal of this research is to discover the mechanisms that underpin peptide-ion selectivity and leverage those mechanisms to design a new class of highly selective membranes. The thermodynamics of peptide-ion complexation will be studied using X-ray absorption spectroscopy, biomolecular characterization techniques, and multiscale modeling. Machine learning will be employed to predict new peptide structures based on thermodynamic descriptors. Newly discovered peptides will be incorporated into electrospun membranes using “click” chemistry. Techno-economic analysis and life cycle assessment will be performed to quantify the environmental and financial impacts the proposed design and inform iterations of this design. Knowledge generated from this research will broadly enable currently challenging selective separations across the fields of membranes and sorbent materials.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.

稀土元素是风力涡轮机、电动汽车和智能手机的关键部件。美国的稀土元素100%从中国进口，在中国通过时间和能源密集型流程进行开采和纯化。美国在从煤炭工业沃茨、电子废物和化肥开采废物等废物流中回收稀土元素方面具有巨大潜力。该项目是凯斯西储大学、克莱姆森大学和宾夕法尼亚州立大学-大学公园之间的合作项目，将从磷石膏中回收有价值的稀土元素（La、Ce、Nd、Pr）。磷石膏是一种肥料采矿废物，与放射性受损的水混合。目前，磷石膏被输送到开放的沟渠或池塘，并作为“堆栈”无限期储存。今天，仅在佛罗里达，估计就有2亿多吨稀土元素被困在未经处理的磷石膏废物中。由于与放射性物质相关的挑战和分离单个元素的困难，这种稀土元素的来源目前尚未开发。此外，烟囱故障对环境造成威胁，因为自1994年以来，磷石膏场地已经导致超过2亿加仑的污染水被释放到佛罗里达含水层和地表沃茨中。因此，该项目的愿景是发现新的分离机制、材料和工艺，从化肥行业的废物流中回收有价值的资源（稀土元素、肥料、清洁水），为稀土元素的可持续国内供应和可持续农业部门铺平道路。这样做将能够回收否则无法使用的废物流，并处理威胁当地供水的受损沃茨。同时，下一代工程师将接受培训，以解决食品-能源-水关系前沿的复杂环境工程问题。教育推广计划将针对使用社交媒体应用程序TikTok的普通公众，并让当地高中生参与研究体验和指导计划。此外，还将为K-12外联活动开展以可持续性和水处理为重点的互动活动。传统的膜分离机制依赖于尺寸和电荷的差异，由于半径相似和形式电荷相同，不足以纯化单个稀土元素。该项目采用多级分离工艺，其中稀土元素1）通过化学消化从磷石膏中提取，2）通过电渗析与阴离子分离并浓缩，3）使用肽功能化膜选择性分离。这项研究的一个关键技术目标是发现支持肽离子选择性的机制，并利用这些机制来设计一类新的高选择性膜。肽离子络合的热力学将使用X射线吸收光谱，生物分子表征技术和多尺度建模进行研究。机器学习将用于基于热力学描述符预测新的肽结构。新发现的肽将被纳入静电纺丝膜使用“点击”化学。将进行技术经济分析和生命周期评估，以量化拟议设计的环境和财务影响，并为该设计的迭代提供信息。从这项研究中产生的知识将广泛地使目前在膜和吸附材料领域具有挑战性的选择性分离成为可能。该奖项反映了NSF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。