Thin film composite membranes containing intrinsic CD cavities in the selective layer

Development of a novel thin film composite membrane by interfacial polymerization on polyetherimide/modified SiO2 support for organic solvent nanofiltration

Synthesis and characterization of novel thin film composite forward osmosis membrane using charcoal-based carbon nanomaterials for desalination application

Interfacially polymerized thin-film composite polyamide membranes: Effects of annealing processes on pervaporative dehydration of aqueous alcohol solutions

Preparation of Thin Film Composite Nanofiltration Membrane by Interfacial Polymerization with 3,5-Diaminobenzoylpiperazine and Trimesoyl Chloride

CO2/CH4 separation using inside coated thin film composite hollow fiber membranes prepared by interfacial polymerization

Interfacial polymerization of thin film selective membrane layers: Effect of polyketone substrates

Performance enhancement of TFC FO membranes with polyethyleneimine modification and post-treatment

Independent control of the extrinsic and intrinsic properties of the polyamide (PA) selective layer is essential for designing thin-film composite (TFC) membranes with performance characteristics required for water purification applications besides seawater desalination. Current commercial TFC membranes fabricated via the well-established interfacial polymerization (IP) approach yield materials that are far from ideal because their layer thickness, surface roughness, polymer chemistry, and network structure cannot be separately tailored. In this work, tailor-made PA-based desalination membranes based on molecular layer-by-layer (mLbL) assembly are presented. The mLbL technique enables the construction of an ultrathin and highly cross-linked PA selective layer in a precisely and independently controlled manner. The mLbL-assembled TFC membranes exhibit significant enhancements in performance compared to their IP-assembled counterparts. A maximum sodium chloride rejection of 98.2% is achieved along with over 2.5 times higher water flux than the IP-assembled counterpart. More importantly, this work demonstrates the broad applicability of mLbL in fabricating a variety of PA-based TFC membranes with nanoscale control of the selective layer thickness and roughness independent of the specific polyamide chemistry.

Improved performance of thin-film composite membrane with PVDF/PFSA substrate for forward osmosis process

Reverse osmosis (RO) is considered as the most widely utilized technique worldwide for water treatment. However, the commercial thin-film composite (TFC) membranes, which are normally made of polyamide (PA) through interfacial polymerization (IP), still experience certain major issues in performance and fabrication. The spin assisted layer-by-layer (SA-LbL) technique was established for overcoming some drawbacks with commercially available PA membranes. Also, recent investigations have recognized the nanoparticle inclusion into the selective layer as a powerful technique for improving the membrane efficiency. Hence, two different methodologies are presented here to improve the membrane performance, i.e., (1) SA-LbL technique to fabricate TFC membrane by the deposition of alternate ultrathin layers of different polyelectrolytes on polysulfone (PSF) commercial ultrafiltration membrane and (2) the nanoclay incorporation into the membranes during IP process to develop TFC membrane. Two types of nanoclays, cloisite (CS)-15A and montmorillonite (MNT), were incorporated to enhance the separation efficiency. This SA-LbL is an innovative method for the RO membrane manufacture, and has not been described earlier to the best of our knowledge. In addition, this work validated for the first time, the efficiency of the two nanoclays at the PA selective layer in the RO membrane. The membrane performance was evaluated using sodium chloride solution in a cross-flow permeation-testing cell for salt rejection and water flux. The results show significant improvement in water flux and salt rejection. The permeation test of 120 bilayers of poly (allylaminehydrochloride)/poly (vinylsulfate) on PSF substrate showed water flux of 37 L/ (m2.h) and salt rejection of 53%, for a 2000-ppm salt solution feed. The highest water flux of 40 L/m2.h with 80% salt rejection, relative to the control membrane was obtained for the membranes containing nanoclays at 25oC temperature, 40.0 bar pressure and 2000 ppm feed concentration. Thus, our study demonstrated that these TFC membranes are promising, and these novel fabrication techniques are great tool to manufacture the RO membrane.

Poly(N-isopropylacrylamide) (PNIPAAm) was introduced into a polyethylene terephthalate (PET) nonwoven fabric to develop novel support for polyamide (PA) thin-film composite (TFC) membranes without using a microporous support layer. First, temperature-responsive PNIPAAm hydrogel was prepared by reactive pore-filling to adjust the pore size of non-woven fabric, creating hydrophilic support. The developed PET-based support was then used to fabricate PA TFC membranes via interfacial polymerization. SEM–EDX and AFM results confirmed the successful fabrication of hydrogel-integrated non-woven fabric and PA TFC membranes. The newly developed PA TFC membrane demonstrated an average water permeability of 1 L/m2 h bar, and an NaCl rejection of 47.0% at a low operating pressure of 1 bar. The thermo-responsive property of the prepared membrane was studied by measuring the water contact angle (WCA) below and above the lower critical solution temperature (LCST) of the PNIPAAm hydrogel. Results proved the thermo-responsive behavior of the prepared hydrogel-filled PET-supported PA TFC membrane and the ability to tune the membrane flux by changing the operating temperature was confirmed. Overall, this study provides a novel method to fabricate TFC membranes and helps to better understand the influence of the support layer on the separation performance of TFC membranes.

Water scarcity has intensified the demand for efficient desalination technologies, making membrane engineering a crucial research focus. A novel type of thin film composite nanofiltration membrane was developed by doping exfoliated molybdenum disulfide nanosheets as fillers within polysulfone and thin film composite membranes. Thin film composite membranes were achieved by interfacial polymerization using m ‐phenylenediamine and trimesoyl chloride monomers. Exfoliated molybdenum disulfide nanosheets were finely dispersed in a polysulfone matrix as observed by optical microscopy. The synergistic integration of molybdenum disulfide nanosheets with the polyamide layer led to improved hydrophilicity, porosity and mechanical strength, promoting rapid water transport. The optimized membrane containing 1.5 wt% molybdenum disulfide achieved a pure water flux of 118 L m −2 h −1 and salt rejection of 40.1% (NaCl) and 64.4% (MgSO₄), compared with 70 L m −2 h −1 , 19.9% and 32.6% for pristine polysulfone. These results highlight the potential of 2D‐material engineering for high‐efficiency water purification. © 2026 Society of Chemical Industry.

Probing the selective salt rejection behavior of thin film composite membranes: A DFT study

Significant progress has been made in recent years in the fabrication of CO2 separation membranes using thin-film composite membranes (TFCs) prepared by the interfacial polymerization (IP) process. However, more advancement is still required to realize the full potential of IP-TFCs in highly permeable/selective gas separation membranes. Here, nitrogen-doped graphene oxide (N-GO) nanosheets and dicationic imidazolium ionic liquids (ILs) with two different aliphatic linkers (i.e., trimethylene and hexamethylene), C3IL and C6IL, respectively, are added in the polyamide (PA) selective layer of a TFC membrane, and the gas separation performance of the membranes is investigated. With the incorporation of the C3IL/N-GO additive, the CO2 permeance and CO2/CH4 and CO2/N2 selectivities of the TFC membranes are increased by 900, 2, and 6%, respectively. On the other hand, the corresponding increases in the CO2 permeance and CO2/gas selectivities, by introducing the C6IL/N-GO additive are 700, 9, and 16%, respectively. These enhancements are attributed to the role of IL molecules in improving the distribution of N-GO nanosheets in the PA selective layer of TFCs, tuning the N-GO sieving channels in favor of CO2 transport, and creating ultrasmall holes which are highly accessible to CO2 molecules. We believe that the incorporation of IL/GO additives into the selective layer of IP-TFCs will pave the way to improving the gas separation performance of thin-film composite membranes.

The uneven permeation of cations and anions through forward osmosis membranes offers a new technical challenge in the development of forward osmosis processes. Cation exchange in polyamide thin film composite membranes is caused by carboxylic acid functional groups within the structure of these membranes’ selective layers. These functional groups will gain or lose a proton depending on the external solution pH. The deprotonation of a polyamide at alkaline pHs results in a net negative charge, allowing for the exchange of cations between feed and draw solutions having monovalent cations. In this study, the importance of solution pH in influencing cation transport across a commercial thin film composite forward osmosis membrane was examined. It was found that cation transport across this membrane varies significantly with changes in pH and occurred fastest at alkaline pH.