Enhanced high-salinity brines treatment using polyamide nanofiltration membrane with tunable interlayered MXene...

Area of Science:

• Materials Science
• Chemical Engineering
• Nanotechnology

Background:

• Nanomaterial interlayers offer a promising strategy for high-performance membranes.
• Thin-film nanocomposite interlayer (TFNi) membranes face challenges in permeability, selectivity, and stability.
• Two-dimensional (2D) materials are explored as potential interlayers for TFNi membranes.

Purpose of the Study:

• To develop a scalable approach for constructing TFNi membranes with enhanced performance.
• To utilize stacked MXene nanosheets as interlayers, templated by Fe3O4 nanoparticles.
• To investigate the impact of the MXene interlayer on membrane properties and separation efficiency.

Main Methods:

• Fabrication of TFNi membranes using stacked MXene nanosheets as interlayers with Fe3O4 nanoparticles as sacrificial templates.
• Characterization of membrane properties using Scanning Electron Microscopy (SEM), X-ray Photoelectron Spectroscopy (XPS), water contact angle, and zeta potential measurements.
• Evaluation of membrane performance in terms of water flux, salt rejection, and separation factor.

Main Results:

• The MXene interlayer increased hydrophilicity, thinness, and roughness of the polyamide layer.
• Sacrifice of Fe3O4 nanoparticles enlarged interlayer channels, significantly boosting water molecule transport.
• The resulting TFNi membranes showed nearly doubled water flux (66.4 L·m⁻²·h⁻¹) and a higher separation factor (48.4) compared to membranes without interlayers.
• Outstanding salt rejection (>97%) was maintained.

Conclusions:

• Stacked MXene nanosheets, templated by Fe3O4 nanoparticles, provide an effective strategy for constructing high-performance TFNi membranes.
• The engineered interlayer channels significantly improve water permeability while preserving selectivity.
• This work presents an innovative method for multifunctional polyamide nanofiltration membrane development.