EFRI ELiS: Three-Dimensional Printable BioReactors For Sustainable Rare Earth Metal Recovery

稀土元素（ree）是一组对现代能源技术和效率至关重要的重元素，如电动汽车电池、节能照明、显示面板和风力涡轮机磁铁。然而，它们是能源密集型的，对开采和净化有害环境；尤其是采矿，可能对弱势社区产生不成比例的影响。近年来，美国国内稀土产量已降至可以忽略不计的水平，使美国依赖于从其他国家进口稀土，这对能源和国家安全产生了重要影响。这项研究的目标是创建封装的工程细菌的3D打印组件，这些细菌将能够以环保的方式选择性地从矿石和工业废物（如煤粉煤灰）中提取稀土。这些印刷的、封装的细菌组件将被整合到膜生物反应器中，在分离膜的帮助下，稀土元素可以很容易地收集。除了进行实验室研究以优化这一生命系统的不同组成部分外，还将评估拟议方法的技术和经济可行性及其对采矿社区的社会、健康、环境和经济影响。通过教育和培训，包括对德克萨斯大学奥斯汀分校的四名研究生的指导，将实现对社会的额外好处。稀土元素可以帮助减少全球对化石燃料的依赖，并且是许多现代技术所必需的。目前的稀土元素提取方法是资源密集型的，对环境有害，在某些情况下对弱势社区的影响不成比例。生物促进稀土的浸出和分离是一个很有前途的选择，但由于基础知识的差距，限制了选择性、吞吐量和可扩展性，仍然具有挑战性。本研究的总体目标是通过高通量打印生物反应器液滴来设计一个生物系统，使其具有功能组织，选择性渗透的结构，能够产生生物还原剂和lanmodulin型蛋白质，从低品位矿石或废物流中提取和浓缩稀土，然后将其分离用于膜生物反应器的收集。具体的研究目标是：1)开发能够产生生物分子的微生物培养物，以增强稀土元素的提取和分离；2)开发智能生物液滴结构，以增强镧系元素的运输和浓度；3)开发具有功能结构的细菌包裹液滴的高通量打印方法；4)将所需的生物反应器液滴结构整合到膜生物反应器中，以实现可持续的稀土元素回收并评估该过程。评估包括用拟议的生物反应器液滴系统取代当前稀土提取技术的伦理、社会、经济、健康、法律、安全和环境影响的评估。这项研究的成功完成将通过提供国内、可持续和可靠的稀土资源，对稀土开采产生变革性的影响。新的研究知识将被纳入大学课程，本科生将参与研究和K-12外展，并为受ree影响的社区创建教育材料。包括扩大参与的计划通过新颖的指导促进留校，通过公民参与激励学生，并通过多学科研究和课程为学生做好准备。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。

Rare Earth elements (REEs) are a group of heavy elements that are critical to modern energy technologies and efficiency such as batteries for electric cars, energy efficient lighting, display panels, and magnets for wind turbines. However, they are energy intensive and environmentally damaging to mine and purify; and mining, in particular, could disproportionally impact disadvantaged communities. In recent years domestic production of REEs has declined to negligible levels making the US dependent on imports from other countries with important implications for energy and national security. The goal of this research is to create 3D printed assemblies of encapsulated, engineered bacteria that will be able to selectively extract REEs from ores and industrial waste products, such as coal fly ash, in an environmentally friendly way. These assemblies of printed, encapsulated bacteria will be integrated into membrane bioreactors where REEs can be easily collected with the help of separation membranes. In addition to conducting laboratory research to optimize different components in this living system, the technical and economic feasibility of the proposed approach and its social, health, environmental, and economic implications for mining communities will be evaluated. Additional benefits to society will be accomplished through education and training including the mentoring of four graduate students at the University of Texas, Austin.Rare earth elements (REEs) can help reduce worldwide dependence on fossil fuels and are necessary for many modern technologies. Current REE extraction methods are resource intensive, environmentally damaging, and in some cases disproportionally impact disadvantaged communities. Biologically promoted leaching and separation of REEs is a promising option but remains challenging due to fundamental knowledge gaps that limit selectivity, throughput, and scalability. The overall goal of this research is to engineer a living system via high-throughput printing of bioreactor droplets into functionally organized, selectively permeable structures capable of producing biological reductants and lanmodulin-type proteins to extract and concentrate REEs from low grade ores or waste streams that can then be separated for collection in membrane bioreactors. The specific research objectives are to: 1) develop microbial cultures that produce biomolecules for enhanced REE extraction and separation, 2) develop smart biological droplet architectures that enhance lanthanide transport and concentration, 3) develop a high-throughput printing method for functionally-structured, bacteria-encased droplets, and 4) integrate the desired bioreactor droplet structures into a membrane bioreactor for sustainable REE recovery and evaluate the process. The evaluation includes assessment of the ethical, social, economic, health, legal, safety, and environmental implications of replacing current REE extraction technologies with the proposed bioreactor droplet system. The successful completion of this research could have transformative impacts on REE extraction by providing domestic, sustainable, and reliable sources. New research knowledge will be incorporated into college courses, undergraduate students will be involved in research and K-12 outreach, and educational materials for REE-impacted communities will be created. The included broadening participation plan promotes retention through novel mentoring, motivates students through civic engagement, and prepares students through multidisciplinary research and coursework.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.