Polyamide Reverse Osmosis Membrane with Cross-linked Antifouling Layer
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional reverse osmosis membranes suffer from fouling, leading to decreased durability and performance, especially when exposed to chlorine and preservation solutions, which affects their flow rate and salt removal efficiency.
Innovation Solution
A polyamide reverse osmosis membrane is developed with a fouling-resistant layer and a protective coating layer formed by cross-linking, using a primary amine compound with hydroxy or alkoxy groups and polyvinyl alcohol with glutaraldehyde, respectively, to enhance durability and antifouling properties.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Object-affected harmful factors
If a coating layer is formed on the polyamide layer to improve antifouling performance, then fouling resistance is improved, but durability in chlorine and preservative solutions deteriorates
Solution Approach 1:
The membrane structure is divided into multiple functional layers: a polyamide layer for separation and a distinct coating layer for antifouling protection. This segmentation allows each layer to optimize its specific function without compromising the other, resolving the contradiction between fouling resistance and durability.
Solution Approach 2:
The invention uses a composite structure combining polyamide material with a coating layer containing antifouling agents. This composite approach enables the membrane to simultaneously achieve separation performance, fouling resistance, and chemical durability by integrating materials with complementary properties.
2Productivity
If conventional reverse osmosis membranes are used, then initial flow rate and salt removal rate are maintained, but performance deteriorates continuously due to fouling
Solution Approach 1:
A coating layer is pre-formed on the polyamide layer before the membrane enters service. This preliminary antifouling protection prevents foulants from adhering to the membrane surface during operation, maintaining high flow rate and salt removal rate throughout the service life and extending the operational duration without performance deterioration.
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 membrane maintains excellent flow rate and salt removal efficiency even after exposure to contaminants and preservation solutions, with a reduced salt removal reduction rate and flow rate reduction ratio, ensuring long-term durability and performance.
Implementation Method 1
a fouling resistant layer which is formed on the polyamide layer; and a protective coating layer which is formed by cross-linking with a fouling resistant layer on the fouling resistant layer
Implementation Method 2
a protective coating layer which is formed by cross-linking with a fouling resistant layer on the fouling resistant layer
Implementation Method 3
reverse osmosis is a phenomenon in which the solvent moves from a solution with a low solute concentration to a solution with a high solute concentration between two solutions that are separated by a semi-permeable membrane
Implementation Method 4
the pressure acting on the side of a solution with a high concentration of solute due to the movement of the solvent is called osmotic pressure
Data Source
AI summary
The present invention relates to a polyamide reverse osmosis membrane including a porous support; a polyamide layer which is formed on at least one surface of the porous support; a fouling resistant layer which is formed on the polyamide layer; and a protective coating layer which is formed on the fouling resistant layer and linked by cross-linking with the fouling resistant layer, and more specifically to a polyamide reverse osmosis membrane having excellent durability and antifouling properties in which antifouling properties are improved, but there is no decrease in flow rate and salt removal rate, and there is little decrease in physical properties due to fouling and little change over time due to a preservation solution, and chlorine durability is also excellent.