High Performance Water Desalination Using Propagating Ion Concentration Shock Waves

化学和生物分离计划的NSF奖项支持斯坦福大学的Juan圣地亚哥教授开发高效海水和苦咸水淡化（离子去除）设备的工作。 目前，美国面临着人口增长和淡水资源减少的同时，因此海水淡化对实现可持续水管理将变得越来越重要。然而，目前的脱盐方法存在高能量和/或基础设施成本的问题。 为了努力开发新的方法来降低这些成本，圣地亚哥的小组正在研究由浓度极化产生的离子浓度冲击波。 浓差极化是在一个电场作用于被称为离子交换膜的特殊膜时产生的。 这种浓差极化描述了在膜的一侧上产生富集离子浓度的区域，以及在膜的相对侧上产生耗尽（脱盐）离子浓度的区域。 感兴趣的波是尖锐的、移动的界面，其约束离子富集和耗尽的生长区域。 圣地亚哥小组将专注于进行受控实验和开发关键现象的模型，这些模型将用于开发高效设备。该小组将开发原型脱盐设备，产生少量的试验脱盐水。 该小组将吸引本科生，并将这项研究的材料纳入工程课程。

This NSF award by the Chemical and Biological Separations program supports work by Professor Juan Santiago at Stanford University to develop highly efficient sea and brackish water desalination (ion removal) devices. Currently, the US faces simultaneous population growth and a decline in freshwater resources, so that desalination will become increasingly important towards realizing sustainable water management. However, current desalination methods suffer from high energy and/or infrastructure costs. In an effort to develop new methods which reduce these costs, Santiago's group is researching ion concentration shock waves created by concentration polarization. Concentration polarization arises when an electric field is applied across specialized membranes called ion exchange membranes. This concentration polarization describes the creation of a region of enriched ion concentration on one side of the membrane, and the associated creation of a region of depleted (desalinated) ion concentration on the opposite side of the membrane. The waves of interest are sharp, moving interfaces which bound growing regions of ion enrichment and depletion. The Santiago group will focus on performing controlled experiments and developing models of key phenomena, which will be utilized to develop highly efficient devices. The group will develop prototype desalination devices which generate small, test-amounts of desalinated water. The group will engage undergraduate students and incorporate material from this research into engineering curriculum courses.