Multilayered Ion Exchange Membrane Rectifying Properties
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional ion exchange membranes used in seawater desalination facilities suffer from scale formation due to bidirectional ion conductivity, leading to reduced efficiency, increased maintenance costs, and potential membrane damage when operated in reverse polarity conditions.
Innovation Solution
A multilayered ion exchange membrane is manufactured with rectifying properties by forming a base layer with a larger number of ion channels and a coating layer with a smaller number of ion channels, using a specific blend of polymers and solvents to control ion channel density asymmetry, preventing scale generation in reverse polarity conditions.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If conventional ion exchange membranes are used with bidirectional ion conductivity, then ion exchange efficiency is maintained, but scale forms on electrodes during reverse polarity operation reducing efficiency and requiring maintenance
Solution Approach 1:
The patent applies asymmetry by creating a multilayered ion exchange membrane with asymmetric ion channel distribution. The first layer has a higher density of ion channels while the second layer has a lower density, creating an asymmetric structure that enables rectifying properties. This asymmetric configuration allows ions to flow more easily in the forward direction while blocking reverse flow, preventing scale formation on electrodes during reverse polarity operation while maintaining ion exchange efficiency.
Solution Approach 2:
The patent segments the ion exchange membrane into multiple layers with different ion channel densities. By dividing the membrane into a first layer with higher ion channel density and a second layer with lower ion channel density, the invention creates distinct functional zones. This segmentation allows the membrane to exhibit rectifying behavior where the combination of layers works together to control ion flow directionality, preventing scale formation while maintaining overall ion exchange performance.
2Productivity
If ion channel density is increased to improve ion exchange efficiency, then ionic conductivity increases, but membrane resistance decreases and mechanical durability is compromised
Solution Approach 1:
The patent applies local quality by varying the ion channel density in different regions of the membrane. The first layer has a higher ion channel density to maximize ion exchange efficiency, while the second layer has a lower ion channel density to maintain mechanical strength and structural integrity. This local differentiation allows each layer to optimize for its specific function, with the first layer driving ion exchange performance and the second layer providing mechanical support and durability.
Applied Scientific Principles
This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.
Function Achieved in This Case
The method enhances ion exchange efficiency by preventing scale formation and reducing maintenance costs, while maintaining ion selectivity without complex processing changes to ion channel geometry or charge distribution.
Implementation Method 1
In general, ion exchange membranes are manufactured by phase separation of polymer electrolytes. That is, at the molecular level, a hydrophilic region and a hydrophobic region composed of negatively or positively charged functional groups exist in a state of fine phase separation.
Implementation Method 2
understanding of the Donnan exclusion phenomenon in 1930, which is a selective transmission phenomenon of ions due to ionic bonding of immobile ions in an ion exchange membrane in an electrolyte solution.
Implementation Method 3
imparting rectifying properties of enabling ions to more easily flow in a specific direction by causing m ion channels to be formed in the coating layer
Data Source
AI summary
The present disclosure provides a method for manufacturing a multilayered ion exchange membrane with rectifying properties and to a multi-layered ion exchange membrane manufactured thereby. More specifically, the present disclosure provides a method for manufacturing a multilayered ion exchange membrane, and a multilayered ion exchange membrane manufactured thereby, the method including a step of integrally forming a coating layer designed to have a fewer number of ion channels on a base layer having a large number of ion channels, thereby preventing scale generation even under a reverse polarity condition, resulting in improvement in ion exchange efficiency. The method effectively controls the asymmetry of the density (number) of ion channels so that the produced ion exchange membrane can have both the ion selectivity and rectifying properties, without using complicated process of, for example, changing the geometric size of the ion channels or the charge distribution inside the ion channels.