目前的指令规范了电透析中的层层地单面涂层的离子交换膜间的离子传输
Alaaeldin A E Elozeiri1, Jouke E Dykstra1, Rob G H Lammertink2
1Environmental Technology, Wageningen University & Research, Bornse Weilanden 9, 6708 WG Wageningen, The Netherlands.
ACS applied materials & interfaces
|March 30, 2025
概括
聚乙醇多层 (PEM) 涂层膜在电透析中显示不对称的离子传输,电流方向显著影响性能和电阻. 这一发现对于优化选择性离子分离和盐水管理应用至关重要.
科学领域:
- 材料科学 材料科学 材料科学
- 电化学 电化学 电化学
- 化学工程是化学工程的重要组成部分.
背景情况:
- 多电解质多层 (PEM) 修改膜是电透析 (ED) 中选择性离子分离的关键.
- 应用包括可持续的盐水管理和资源回收.
- 了解通过PEM涂层膜的离子运输对于优化ED过程至关重要.
研究的目的:
- 通过PEM涂层的阴离子交换膜 (CEM) 调查离子运输机制.
- 分析与双价离子 (Mg2+,Ca2+) 观察到的不对称电流电压反应.
- 为了确定基膜特性和离子类型对PEM性能的影响.
主要方法:
- 一层一层 (LbL) 技术用于用PEM涂覆商业CEM.
- 电化学表征,包括电流-电压 (I-V) 测量.
- 离子运输模型用于解释观察到的现象.
主要成果:
- PEM涂层诱导了不对称的I-V反应,当涂层面向对电传输方向时,观察到限制电流密度.
- 涂层膜的抗性显著增加,特别是与Mg2+和Ca2+离子.
- PEM性能与基膜电阻和固定电荷密度相关;更高的基电阻导致更高的PEM电阻.
- 离子价值的影响很小,这表明介电排斥是微不足道的.
结论:
- 用PEM涂层的膜表现出对ED应用至关重要的方向依赖的离子传输.
- 基本膜的特性显著影响PEM性能.
- 该研究提供了对优化基于PEM的膜进行选择性离子分离和盐水管理的见解.
相关概念视频
What is an Electrochemical Gradient?
Adenosine triphosphate, or ATP, is considered the primary energy source in cells. However, energy can also be stored in the electrochemical gradient of an ion across the plasma membrane, which is determined by two factors: its chemical and electrical gradients.
The chemical gradient relies on differences in the abundance of a substance on the outside versus the inside of a cell and flows from areas of high to low ion concentration. In contrast, the electrical gradient revolves around an ion’s...
The chemical gradient relies on differences in the abundance of a substance on the outside versus the inside of a cell and flows from areas of high to low ion concentration. In contrast, the electrical gradient revolves around an ion’s...
Ion Channels
The movement of ions like sodium, potassium, and calcium into and out of the cell is essential to maintain the electrochemical gradient in living cells. The ion channels—a class of membrane transport proteins—help maintain this ionic gradient for the smooth functioning of physiological activities such as maintaining cell size and volume, conducting nerve impulses, and gas and nutrient exchange.
Ion channels are specialized integral membrane proteins on the plasma membrane that allow specific...
Ion channels are specialized integral membrane proteins on the plasma membrane that allow specific...
Dialysis
Dialysis is a diffusion-based purification process that separates analyte molecules from a complex matrix. This is accomplished by allowing molecules in the solution to pass through a semipermeable membrane into a liquid on the other side. The membrane is usually made of cellulose acetate or cellulose nitrate, and the second liquid must be miscible with the solution. Ions (e.g., chloride or sodium) or organic molecules (e.g., glucose) can pass through the membrane pores, which generally have...
Ion Exchange
Ion exchange chromatography separates charged molecules from a solution by reversibly exchanging them with mobile, or 'active', ions associated with the oppositely charged stationary phase. This method can be used to separate ions, soften and deionize water, and purify solutions. The polymers comprising the ion-exchange column are high-molecular-weight and chemically stable polymers, crosslinked to be porous and essentially insoluble. They are also functionalized with either acidic or basic...
Electrochemical Gradient and Channel Proteins: An Overview
An electrochemical gradient is a fundamental concept in biology and chemistry. It regulates the movement of ions across cell membranes. This movement is influenced by two factors:
The electrical gradient: The electrical gradient across cell membranes refers to the difference in electric charge between the inside and outside of a cell. This difference drives the movement of ions towards or away from the cells. For instance, if the inside of the cell is more negatively charged relative to the...
The electrical gradient: The electrical gradient across cell membranes refers to the difference in electric charge between the inside and outside of a cell. This difference drives the movement of ions towards or away from the cells. For instance, if the inside of the cell is more negatively charged relative to the...
The Electrical Double Layer
In the region where two bulk phases meet, an intricate electric charge distribution arises due to charge transfer, ion adsorption, molecular orientation, and charge distortion. This complex distribution is commonly referred to as the electrical double layer.When a solid electrode interfaces with ions in an electrolyte solution, the speed of electron transfer dictates the rates of oxidation and reduction. The electrode acquires a charge through the escape of atoms into the solution as cations or...


