EAGER: SusChem: Enhanced Electricity Production from Engineered Salinity Gradients Using Capacitive Mixing

目前正在探索几种从盐度梯度中获取电能的技术，这些盐度梯度可能是自然存在的（例如，海水和河水），也可能是经过改造的（例如，利用废热和热解盐）。电容和伪电容混合（CapMix）是利用盐度梯度产生能量的最新方法之一。在这种方法中，电容电极交替暴露于具有高盐浓度和低盐浓度的溶液中。与其他正在探索的技术（例如，延迟压力渗透，PRO和反电渗析，RED）相比，CapMix具有关键优势，因为它不需要膜材料，而膜材料通常非常昂贵。然而，到目前为止，CapMix的功率密度比这些基于膜的工艺要低。该项目的目的是通过对碳电极表面进行化学改性和测试新型金属基电极来提高CapMix的发电量。盐度梯度能源的使用为渴望找到生产碳中和电力的新方法的年轻科学家和工程师提供了一个机会。盐度梯度发电的高度跨学科性质提供了一个独特的机会，展示了跨越溶液和表面化学、水质、可再生材料、工程经济学和电力生产的不同技术领域。为了传达有关盐度梯度能量的信息，建议创建一个网站和YouTube视频，告诉学生如何制作和测试这些设备，以便他们可以为家庭和学校学习以及科学展览建造这些系统。这将通过实验和通过互联网的自我激励学习来鼓励创造性和在家学习，PI过去在高中学生咨询方面取得了成功。该项目的研究结果可能对使用碳中和技术的全球能源生产产生重要影响，并通过从废热中回收能源等过程进一步推动实现水基础设施的能源可持续性。迄今为止，CapMix研究使用NaCl溶液来产生盐度梯度。该项目将重点关注一种新方法，即使用可在低温（45摄氏度）下蒸馏的热解盐（即碳酸氢铵，AmB）或化学品（氨）。主要目的是证明，通过使用新的、未经测试的金属和化学改性碳电极热解溶液，CapMix的发电量可以大幅提高。目前还没有关于这种材料和热解化学物质的独特组合的数据，这些实验将提供一个概念的证明，即改变电极类型和化学成分可以通过扩大电压窗口来提高性能。对于金属电极，该团队将测量使用新型锰、银或铜基电极产生的功率密度。对于碳电极，我们将研究使用氧化处理、酸性处理和特定化学物质的结合对表面化学变化性能的影响。这项工作的部分指导是成功地修改了活性炭，使其在硫酸溶液中发挥超级电容器的作用，尽管这里的AmB溶液条件将完全不同，因此趋势可能与以前的结果不同。这种方法被认为是基于可持续化学的，因为大多数材料（例如碳电极、氨）在地球上是丰富的，并且在闭环系统中使用。

146489LoganSeveral technologies are being explored to capture electrical energy from salinity gradients, which may exist naturally (e.g., seawater and river water) or be engineered (e.g., by using waste heat and thermolytic salts). One of the newest methods to produce energy from salinity gradients is capacitive and pseudo-capacitive mixing (CapMix). In this approach, capacitive electrodes are alternately exposed to solutions having high and low salt concentrations. CapMix has a critical advantage over other technologies being explored (e.g., pressure retarded osmosis, PRO; and reverse electrodialysis, RED) in that it does not require membrane materials, which are often prohibitively expensive. To date, however, CapMix has produced lower power densities than these membrane-based processes. The purpose of this project is to improve power production using CapMix through chemical modification of carbon electrode surfaces and testing novel metal-based electrodes. The use of salinity gradient energy is an opportunity to reach out to young scientists and engineers that are eager to find new ways to produce carbon-neutral electricity. The highly interdisciplinary nature of power production from salinity gradients presents a unique opportunity to showcase different technical fields that span solution and surface chemistry, water quality, renewable materials, engineering economics, and electrical power production. To convey information on salinity gradient energy, it is proposed to create a website and YouTube videos to inform students how to make and test these devices so that they could build these systems for home and school studies and science fairs. This will encourage creativity and learning at home through experimentation and through self-motivated learning via the internet, where the PI has had success in the past with high school student inquiries. The findings of this project could have important implications for global energy production using carbon-neutral technologies, and further advance achieving energy sustainability of the water infrastructure through such processes as energy recovery from waste heat.To date, CapMix studies have used NaCl solutions to generate salinity gradients. This project will focus on a new approach that uses a thermolytic salts (i.e., ammonium bicarbonate, AmB) or chemicals (ammonia) that can be distilled at low temperatures (45 degrees C). The main objective is to demonstrate that CapMix power production can be substantially increased by using new, un-tested thermolytic solutions with metal and chemically-modified carbon electrodes. There are no data on this unique combination of materials and thermolytic chemicals, and these experiments will provide a proof of concept that altering the electrode type and chemistry can increase performance by widening the voltage window. For the metal electrodes, the team will measure the power densities generated by using novel manganese, silver, or copper based electrodes. For the carbon electrodes, we will examine the effects on performance of surface chemistry alterations using oxidative treatments, acidic treatments, and the bonding of specific chemicals. The work is guided in part by the success of modifying activated carbon to function as supercapacitors in sulfuric acid solutions, although here the AmB solution conditions will be sufficiently different such that the trends will likely differ from previous results. This approach is considered to be based on sustainable chemistry, as most of the materials (e.g., carbon electrodes, ammonia) are Earth-abundant and are used in closed-loop systems.