Department of Mechanical Engineering, Pohang University of Science and Technology (POSTECH), San 31, Hyoja-dong, Pohang, 790-784, Republic of Korea.
Department of Mechanical Engineering, Pohang University of Science and Technology (POSTECH), San 31, Hyoja-dong, Pohang, 790-784, Republic of Korea.
Anal Biochem. 2019 Jul 15;577:21-25. doi: 10.1016/j.ab.2019.04.007. Epub 2019 Apr 11.
Spontaneous filtration without a power supply was investigated using highly charged precursor mixtures instead of recognized microfluidic desalination techniques. The proposed filtration method consisted of a main channel (depth: 1 mm) and shallow channels (depth: 400 μm) in which the precursor mixture was injected. The filtration performance of the proposed device was evaluated by injecting a fluorescent dye that moved toward the centerline of the main channel. The respective rejection rates of CaCl, NaCl, CaSO, and NaSO were 3.16%, 30.13%, 43.74%, and 36.32%, respectively. This trend can be explained by the mechanism of Donnan exclusion theory. The focusing of charged species toward the centerline of the main channel was caused by highly charged surfaces. The proposed filtration method exhibited a migration of charged microparticles toward a certain direction. This particle migration behavior was consistent with the simulation data. These results suggested that the proposed filtration method had strong potential for desalinating brackish water or salty surface water without an external power supply.
利用高电荷前驱体混合物代替公认的微流道脱盐技术，研究了无电源的自发过滤。所提出的过滤方法由主通道（深度：1mm）和浅通道（深度：400μm）组成，在前驱体混合物被注入到这些通道中。通过注入荧光染料来评估所提出的装置的过滤性能，该染料朝着主通道的中心线移动。CaCl、NaCl、CaSO 和 NaSO 的相应截留率分别为 3.16%、30.13%、43.74%和 36.32%。这种趋势可以用唐南排斥理论的机制来解释。带电荷的物质由于高电荷表面而聚焦到主通道的中心线。所提出的过滤方法表现出带电微粒朝着特定方向的迁移。这种粒子迁移行为与模拟数据一致。这些结果表明，所提出的过滤方法具有在没有外部电源的情况下淡化咸水或咸地表水的强大潜力。
