离子交换膜中的选择性吸附:溶液离子组成对离子分割的影响
S Ozkul1, O Arbabzadeh2, R J M Bisselink3
1Environmental Technology, Wageningen University & Research, Bornse Weilanden 9, Wageningen 6708 WG, the Netherlands.
Water research
|March 12, 2024
概括
了解离子交换膜是可持续再利用水的关键. 这项研究表明,离子度如何影响膜对和离子的选择性,从而提高了电透析的性能.
科学领域:
- 膜科学和技术 膜科学和技术
- 水处理和海水淡化工作.
- 物理化学 物理化学
背景情况:
- 电透析 (ED) 是水淡化和再利用的重要技术.
- ED膜的选择性受溶液离子组成的影响,影响水吸收和电荷密度.
- 优化ED性能需要了解膜内的离子特异相互作用.
研究的目的:
- 研究离子交换膜中Na+和K+离子的选择性吸附.
- 分析不同溶液离子组成对膜水体积分数和离子选择性的影响.
- 开发一个理论框架来预测膜中的离子吸附行为.
主要方法:
- 进行了各种度的Na+,K+,Li+,Ca2+和Mg2+离子的膜吸附实验.
- 在不同的离子条件下测量膜水体积分数.
- 开发了一种基于Bublik-Mansoori-Carnahan-Starling-Leland (BMCSL) 理论的理论模型,其中包含了体积效应.
- 在电透析过程中使用实验数据和理论计算评估了选择性离子去除.
主要成果:
- 增加的总离子度和双价离子含量减少了膜水体积分数.
- 减少的水体积分数增强了K+对Na+离子的选择性吸附.
- 开发的理论框架准确地描述了离子分区,考虑到体积效应,如尺寸排除.
- 溶液中的离子组成显著影响了电透析中的选择性离子去除.
结论:
- 膜水体积分数是电透析期间离子选择性的关键因素.
- 对于准确的离子分区模型,必须考虑体积学效应,例如尺寸排除.
- 这项研究为改善用于水再利用应用的离子交换膜的设计和性能提供了一个框架.
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