Effect of Interlayer Construction on TFC Nanofiltration Membrane Performance: A Review from Materials Perspective

Abstract

Polyamide (PA) thin-film composite (TFC) nanofiltration (NF) membranes, which are extensively utilized in seawater desalination and water purification, are limited by the upper bounds of permeability-selectivity. Recently, constructing an interlayer between the porous substrate and the PA layer has been considered a promising approach, as it may resolve the trade-off between permeability and selectivity, which is ubiquitous in NF membranes. The progress in interlayer technology has enabled the precise control of the interfacial polymerization (IP) process, which regulates the structure and performance of TFC NF membranes, resulting in a thin, dense, and defect-free PA selective layer. This review presents a summary of the latest developments in TFC NF membranes based on various interlayer materials. By drawing from existing literature, the structure and performance of new TFC NF membranes using different interlayer materials, such as organic interlayers (polyphenols, ion polymers, polymer organic acids, and other organic materials) and nanomaterial interlayers (nanoparticles, one-dimensional nanomaterials, and two-dimensional nanomaterials), are systematically reviewed and compared. Additionally, this paper proposes the perspectives of interlayer-based TFC NF membranes and the efforts required in the future. This review provides a comprehensive understanding and valuable guidance for the rational design of advanced NF membranes mediated by interlayers for seawater desalination and water purification.

Tannic Acid-Functionalized MoS2 and g-C3N4 Thin Film Lamellar Membranes for Improved Permeance and Rejection in Nanofiltration

“…Unfortunately, good permeance, selectivity, and fouling issues still exist in current TFC membranes, unlike in the thin-film nanocomposite (TFN) membranes, which are made by incorporating nanomaterials. Different morphologies, i.e., one-dimensional (1D) and two-dimensional (2D) nanomaterials, exhibit a significant difference in their impact on the PA layer and transport properties of the membrane, and this can significantly enhance the separation performance . For instance, lamellar assembly of low-dimensional materials of 1D nanoparticles enables the easy passage of water, while 2D structures facilitate the blocking of the passage of larger solutes. , So, it is likely that the combined morphology of nanomaterials can offer synergistic effects …”

Experimental and Modeling Study of the Nanofiltration of Alcohol-Based Molecules and Amino Acids by Commercial Membranes

“…NF membranes contain three porous stacked layers of different polymers. The top layer (also called the active layer) is composed of an imperfect crosslinking polymer containing ionizable groups, which confer a specific charge to the membrane depending on the characteristics of the feed solutions [ 6 ]. In general, NF membranes are amphoteric, positively charged, negatively charged, or have zero net charge, depending on the pH of the feed solution [ 7 , 8 ].…”