Doctor-blading-assisted interfacial polymerization for green and scalable polyamide membrane fabrication

Area of Science:

• Materials Science
• Chemical Engineering
• Environmental Science

Background:

• Polyamide membranes are crucial for water purification but current fabrication methods using alkane-water interfaces have limitations.
• Existing interfacial polymerization (IP) techniques offer poor control over reaction conditions, leading to suboptimal membrane microstructure and performance.
• The use of volatile alkane solvents in traditional IP poses environmental concerns.

Purpose of the Study:

• To develop an improved interfacial polymerization (IP) strategy for fabricating high-performance polyamide membranes.
• To enhance control over kinetic and thermodynamic factors during IP by utilizing an ionic liquid/water interface.
• To create a scalable, eco-friendly, and efficient method for producing advanced thin-film composite membranes.

Main Methods:

• Implemented an interfacial polymerization (IP) strategy at an ionic liquid/water interface.
• Utilized the high viscosity and low volatility of ionic liquids to control the reaction zone.
• Integrated the doctor blading technique for rapid, scalable membrane production.

Main Results:

• Achieved synchronous kinetic and thermodynamic control of the interfacial reaction, optimizing polyamide membrane microstructure.
• Developed a rapid, eco-friendly, and scalable fabrication process for polyamide membranes.
• The resulting membranes demonstrated high pure water permeance (25.8 LMH/bar) and excellent salt rejection (96.54% for sodium sulfate).

Conclusions:

• The ionic liquid/water interface strategy offers superior control over IP, leading to enhanced membrane performance.
• This facile fabrication method enables the production of next-generation, high-performance thin-film composite membranes.
• The process is eco-friendly, scalable, and suitable for industrial application, addressing limitations of current methods.