HU Yaru¹, ZHANG Dongxiang², LI Zirui¹

(1. School of Mechanical Engineering, National Engineering Research Center for Technological Innovation Method and Tool, Hebei University of Technology, Tianjin 300401, China; 2. Biological Engineering Department, Utah State University, Logan 84321, USA)

Abstract：In order to solve the problem of difficult ion separation under high Mg2⁺-Li⁺ concentration ratio, a numerical simulation system for ion separation based on force field modulation was proposed in this paper. The system regulated the flow field distribution of the system by introducing horizontal barriers in a specific positional relationship. Based on the difference in electrophoretic mobility of lithium and magnesium, the separation of magnesium and lithium ion was achieved by diffusing the 2 ions in a path with different angles to the horizontal direction under the action of electric field forces and fluid flow forces. This study used computational fluid dynamics methods for numerical simulation, and explored the response law of the system to voltage, flow rate and barrier parameters by analyzing the behavior of ions under the flow field regulation. The horizontal barrier divided the channel into a region with a wide middle and a narrow boundary. The flow field was stabilized at the ion outlet to narrow the sampling space for ions, and the direction of the inlet flow was controlled to be close to the lithium ion separation trajectory, resulting in higher quality and stability of ion separation. In this study, numerical simulations were carried out using diluted salt lake brine solutions. The results show that the system can recover 93% of lithium ions and increase the recovery of magnesium ions to 95% at a voltage of 11.5 V and a fluid flow velocity of 990 μm/s. The ion separation system based on the force field modulation mechanism can achieve efficient separation of chemically similar lithium and magnesium ions.

Keywords：ion separation; electrophoresis; numerical simulation; force field modulation

Get Citation：HU Y R, ZHANG D X, LI Z R. Numerical simulation of ion separation based on force field modulation mechanism[J]. China Powder Science and Technology, 2023, 29(5): 101-111.

DOI：10.13732/j.issn.1008-5548.2023.05.012

Received：2023-05-27,Revised：2023-07-20,Online：2023-08-29 16：26。

Funding Project：国家自然科学基金项目,编号:12072100。

First Author：胡雅茹(1997—),女,硕士研究生,研究方向为微纳流体力学。E-mail: 202031205119@stu.hebut.edu.cn。

Corresponding Author：李子瑞(1969—),男,教授,博士,博士生导师,研究方向为微纳流体力学。E-mail: lizirui@gmail.com。