Internal Concentration Polarization Research Articles

Analysis of the effect of advanced FO spacer on the specific energy consumption of hybrid RO desalination system

Research involving hybrid forward osmosis-reverse osmosis (FO-RO) desalination has gained attention recently due to its potential to reduce energy consumption compared to traditional RO. This paper aims to understand the degree of the impact of advanced spacers in the FO process on the overall specific energy consumption (SEC) of FO-RO systems. The SEC for a representative advanced spacer is simulated and analysed under standard recovery and operating conditions. The results show that advanced spacers can significantly reduce SEC by up to 9.27% under the operating conditions considered. The results also show that placing an advanced spacer on the FO membrane draw side has a greater effect in reducing SEC compared to placing it on the feed side, due to the larger extent of ECP. It was found that FO channel pressure drop has insignificant impact on the SEC. The performance of advanced spacers in SEC reduction is most effective if the contribution of external concentration polarisation (ECP) to transmembrane osmotic pressure is high, if the contribution of internal concentration polarisation (ICP) is low, and if the effective transmembrane osmotic pressure is low. Optimal mixing in FO systems is therefore crucial to reduce SEC, especially for systems with severe ECP.

Zwitterionic forward osmosis membrane with low structural parameter based on highly porous polyvinylidene fluoride substrate for desalination

Polyamide thin-film composites (PA-TFC) forward osmosis (FO) membranes have great potential in wastewater treatment and desalination. However, they are continuously studied to further enhance the FO performances from the improvement of the PA layer and the substrate individually. Here, a polyvinylidene fluoride/poly(hydroxyethyl methacrylate) (PVDF/PHEMA) membrane with a highly porous surface was fabricated and used as the substrate to engineer a thin and rough PA layer. After being post-modified by zwitterionic groups, the resulting membrane (namely TFC90-Z) has a much lower structure parameter ( S , 216 ± 12 µm) in comparison to common FO membranes in literature, thus decreasing internal concentration polarization and increasing FO performances. Specific salt flux ( J s /J w ) and water flux ( J w ) of TFC90-Z are 0.03 ± 0.01 g/L and 18.5 ± 0.4 L m -2 h -1 under the active layer-facing draw solution (AL-DS) orientation using 1.0 M NaCl as the draw solution and deionized water as the feed solution. Meanwhile, NaCl rejection is 91.6 ± 0.1%. This work offers an efficient way to engineer excellent PA-TFC FO membranes for aqueous separation and desalination. • PA-TFC FO membranes were fabricated on highly porous PVDF/PHEMA substrates via IP. • The PA layer was post-modified by zwitterionic groups via co-deposition of TA and AEPPS. • ICP is weakened due to the low structure parameter of the zwitterionic PA-TFC FO membrane. • The as-prepared FO membrane has excellent FO performances especially specific salt flux ( J s /J w ).

Polymer-Grafted Graphene Oxide as a High-Performance Nanofiller for Modification of Forward Osmosis Membrane Substrates

A substrate with good physicochemical properties is essential for minimizing unpleasant internal concentration polarization phenomena in a forward osmosis (FO) process. In this study, graphene oxide-graft-poly(2-hydroxy ethyl methacrylate) (GO-g-PHEMA, GP) nanoplates with different weight ratios were prepared for the first time using a combination of click chemistry and reversible addition–fragmentation chain-transfer polymerization. Then, high-efficiency thin-film nanocomposite (TFN) FO membranes were fabricated using GP-modified polysulfone (PSf) substrates. The influence of the structure parameter and concentration of GP on the substrate and polyamide (PA) active layer properties were systematically studied using various characterization methods. The obtained results indicated that the morphologies of the GP-modified PSf substrates were more porous, and the pure water flux, surface hydrophilicity, and mean pore size of the substrates considerably improved. Furthermore, the GP/PSf-based TFN membranes showed thicker, rougher, and permeable PA active layers than the baseline PSf-based TFC membrane. In the case of TFN-FO membranes, the water permeability noticeably increased, and the structural parameter effectively declined. Additionally, the FO performance dramatically improved (e.g., the water flux of TFN-GP210.4 reached 32.6/15.6 LMH under PRO/FO configuration). According to the results, it can be concluded that 0.4 wt % of GP21 nanofiller (GO/PHEMA ratio of 2:1) was the optimal blend concentration. Also, the modified membranes showed a noticeable performance in Caspian seawater desalination.

Fulvic and alginic acid separation during pressure retarded osmosis: Governing effects and fouling mechanisms

In this study, the performance of model foulant (alginate and fulvic acid) separation by pressure retarded osmosis (PRO) was systematically studied. At the various operating conditions tested, fulvic acid had a greater flux decline and power density loss than alginate. The results of membrane resistance test, SEM-EDX images, and the solute diffusion coefficient K demonstrated that fulvic acid was more likely to clog the inside of the porous support layer of the PRO membrane, which would exacerbate the internal concentration polarization (ICP) phenomena. Although model foulants were successfully removed by PRO (with a retention rate of about 95.0%), the presence of either calcium or magnesium ions was detrimental to the fouling process of PRO membranes. According to the XDLVO theory analysis results, the presence of calcium or magnesium ions increased foulant adhesion to the PRO membrane, thereby resulting in membrane fouling. In addition, Pearson correlation coefficient also showed that the hydrodynamic conditions (effective osmotic pressure difference as well as operating hydraulic pressure acting vertically to the membrane and parallel to the membrane cross-flow shear force) had an important effect on the degree of membrane fouling. This is attributed to the influence of the hydrodynamic conditions on the initial influence water flux and thus on the fouling of the PRO membrane.

Ammoniacal nitrogen concentration by osmotically assisted reverse osmosis

Ammoniacal nitrogen is a commonly encountered nitrogenous pollutant produced by industrial processes present in wastewater. In this work, model wastewater containing ammoniacal nitrogen (in the form of NH4Cl) was used as a feed solution in the demonstration of osmotically assisted reverse osmosis (OARO) using a multi-stage hollow fiber membrane module setup. The OARO process aimed to dewater the model wastewater and effectively concentrate the ammoniacal nitrogen in solution for easier recovery. Split feed OARO, wherein the feed stream is split either into the concentrated retentate or refluxed back into the permeate side flowing counter-current with the feed, was conducted and the influence of several operational parameters, such as applied pressure, feed flow rate, reflux ratio, on the concentration process was investigated. Also, the properties of the feed solution, i.e. initial feed concentration and presence of other ionic species, such as NaCl, were also tested. Higher concentration efficiency was observed at the following conditions: higher applied pressure, lower flow rate, and higher reflux ratio. The use of low concentrated feed solutions might be useful to decrease the applied pressure and the occurrence of internal concentration polarization was also avoided. The results in this work show that OARO could be a practical membrane-based process for enrichment and recovery of ammoniacal nitrogen from wastewater to further realize a circular economy, in which waste materials such as ammoniacal nitrogen are recovered and reused to produce valuable products.

Impacts of Calcium Addition on Humic Acid Fouling and the Related Mechanism in Ultrafiltration Process for Water Treatment.

Humic acid (HA) is a major natural organic pollutant widely coexisting with calcium ions (Ca2+) in natural water and wastewater bodies, and the coagulation-ultrafiltration process is the most typical solution for surface water treatment. However, little is known about the influences of Ca2+ on HA fouling in the ultrafiltration process. This study explored the roles of Ca2+ addition in HA fouling and the potential of Ca2+ addition for fouling mitigation in the coagulation-ultrafiltration process. It was found that the filtration flux of HA solution rose when Ca2+ concentration increased from 0 to 5.0 mM, corresponding to the reduction of the hydraulic filtration resistance. However, the proportion and contribution of each resistance component in the total hydraulic filtration resistance have different variation trends with Ca2+ concentration. An increase in Ca2+ addition (0 to 5.0 mM) weakened the role of internal blocking resistance (9.02% to 4.81%) and concentration polarization resistance (50.73% to 32.17%) in the total hydraulic resistance but enhanced membrane surface deposit resistance (33.93% to 44.32%). A series of characterizations and thermodynamic analyses consistently suggest that the enlarged particle size caused by the Ca2+ bridging effect was the main reason for the decreased filtration resistance of the HA solution. This work revealed the impacts of Ca2+ on HA fouling and demonstrated the feasibility to mitigate fouling by adding Ca2+ in the ultrafiltration process to treat HA pollutants.

Selective separation of volatile fatty acids, nitrogen and phosphorus from anaerobic acidogenic fermentation via forward osmosis membrane process

Selective separation and recovery of volatile fatty acids (VFA) and other valuable resources promotes a sustainable wastewater treatment system, but its cost-effective separation approaches are poorly understood. This study investigated the feasibility of applying a forward osmosis (FO) dewatering process for the selective separation of VFA, ammonium and phosphate from anaerobic acidogenic fermentation. Limited VFA rejection of fermentation broth, i.e., less than 20 %, was observed under acidic conditions, while the rejection rate was significantly increased to ∼90 % at neutral pH. The transfer of ammonium across the membranes was remarkably impacted by the feed solution pH. Lower pH (∼4) values resulted in higher rejection rates of ammonium (∼96 %), and the rate gradually declined as pH increased. The rejection of phosphate, which remained higher than 98 %, was less sensitive to pH variations. The increase in water flux promoted the rejection of VFA, ammonium and phosphate, and the membrane orientation significantly impacted the transfer of nutrients in the FO process. The active layer facing the feed solution (AL-FS) mode exhibited higher rejection rates of VFA, ammonium and phosphate than the active layer facing the draw solution (AL-DS) mode, which was ascribed to the internal concentration polarization effect. Furthermore, approximately 80 % of water could be effectively reduced from a real acidogenic fermentation liquor during the FO process; ammonium and phosphate were 3.72-fold and 4.10-fold concentrated in feed solution, respectively, and VFA was selectively separated in draw solution. The work confirmed the feasibility of utilizing FO processes in separating and enriching VFA, ammonium and phosphate from anaerobic fermentation liquors, providing meaningful information on promoting FO-based processes in treating wastewater.

Forward Osmosis Membranes: The Significant Roles of Selective Layer.

Forward osmosis (FO) is a promising separation technology to overcome the challenges of pressure-driven membrane processes. The FO process has demonstrated profound advantages in treating feeds with high salinity and viscosity in applications such as brine treatment and food processing. This review discusses the advancement of FO membranes and the key membrane properties that are important in real applications. The membrane substrates have been the focus of the majority of FO membrane studies to reduce internal concentration polarization. However, the separation layer is critical in selecting the suitable FO membranes as the feed solute rejection and draw solute back diffusion are important considerations in designing large-scale FO processes. In this review, emphasis is placed on developing FO membrane selective layers with a high selectivity. The effects of porous FO substrates in synthesizing high-performance polyamide selective layer and strategies to overcome the substrate constraints are discussed. The role of interlayer in selective layer synthesis and the benefits of nanomaterial incorporation will also be reviewed.

Impact of Graphene Oxide on Properties and Structure of Thin-Film Composite Forward Osmosis Membranes.

Forward osmosis (FO) membranes have the advantages of low energy consumption, high water recovery rate, and low membrane pollution trend, and they have been widely studied in many fields. However, the internal concentration polarization (ICP) caused by the accumulation of solutes in the porous support layer will reduce permeation efficiency, which is currently unavoidable. In this paper, we doped Graphene oxide (GO) nanoparticles (50~150 nm) to a polyamide (PA) active layer and/or polysulfone (PSF) support layer, investigating the influence of GO on the morphology and properties of thin-film composite forward osmosis (TFC-FO) membranes. The results show that under the optimal doping amount, doping GO to the PA active layer and PSF support layer, respectively, is conducive to the formation of dense and uniform nano-scale water channels perpendicular to the membrane surface possessing a high salt rejection rate and low reverse solute flux without sacrificing high water flux. Moreover, the water channels formed by doping GO to the active layer possess preferable properties, which significantly improves the salt rejection and water permeability of the membrane, with a salt rejection rate higher than 99% and a water flux of 54.85 L·m−2·h−1 while the pure PSF-PA membrane water flux is 12.94 L·m−2·h−1. GO-doping modification is promising for improving the performance and structure of TFC-FO membranes.

Biogenic silver nanoparticles-modified forward osmosis membranes with mitigated internal concentration polarization and enhanced antibacterial properties

Thin-film composite forward osmosis (TFC-FO) membranes show the potential to be applied in water treatment applications. However, the TFC-FO membrane performance was limited by internal concentration polarization (ICP) and membrane fouling. In this study, a well-functioning TFC-FO membrane was produced by embedding biogenic silver nanoparticles (BioAg) into the polysulfone (PSf) substrate of a FO membrane. Effects of BioAg on membrane structure, filtration performance, antifouling, and antibacterial properties of the as-prepared FO membranes were examined. Results indicated that BioAg-modified FO membranes achieved improved surface hydrophilicity, higher porosity, and mitigated ICP, resulting in 2.5–4.4 times higher water flux than the pristine FO membranes. The BioAg-modified FO membrane also showed significantly improved antifouling and antibacterial ability. Moreover, the release velocity of silver nanoparticles in FO membranes was significantly slowed down by the construction of the polyamide layer. After 30 days of immersion in an aqueous solution, 96.5% of silver was retained in the optimized BioAg-modified FO membrane. The study offers an effective approach to simultaneously mitigate ICP and enhance the antifouling property of TFC-FO membranes through substrate modification.

Micro-patterned cellulose triacetate membranes for forward osmosis: Synthesis, performance and anti-fouling behavior

Most cellulose triacetate (CTA)-based studies for forward osmosis (FO) have greatly focused on achieving asymmetric membranes with a highly porous sublayer along with a dense selective layer. Such membranes can achieve better fluxes due to improved mass transfer and reduced internal concentration polarization. In this work, patterning of the CTA-membranes via modification of the conventional non-solvent induced phase inversion is explored as an alternative route to increase FO water flux without reducing salt selectivity. The modified way of applying the non-solvent in this method increased the membrane bulk porosity from ~17 % to ~50 %. Such high porosity and reduced tortuosity of the patterned membrane can reduce the internal concentration polarization by back-transport and reduced accumulation of salt and other solutes in the porous support. During FO, the patterned CTA membrane showed a water flux of 30 L m−2 h−1 and reverse salt flux of 25 g m−2 h−1, thanks to the increased effective membrane area, low water transport resistance, and high porosity of the membrane support. The patterned CTA-membranes may have potential in FO for applications with larger draw solutes due to the slightly larger pores on the membrane surface following the non-solvent spraying. Alternatively, some phase inversion parameters can still be further tuned to lower the salt passage.

Recovery of volatile fatty acids using forward osmosis: Influence of solution chemistry, temperature, and membrane orientation.

This study investigates the suitability of forward osmosis (FO) for recovery of volatile fatty acids (VFAs) from anaerobic digesters (ADs) and identifies the conditions favorable for commercially viable maximum recovery of VFAs. The recovery efficiency of VFAs is evaluated using a polyamide (PA)-based thin-film composite (TFC) membrane. The pH (3, 5, 7, and 9), temperature (20°C and 40°C), and membrane orientation (active-layer [AL]-facing FS and AL facingDS) were changed, and water flux, reverse salt flux (RSF), rejection rate, and concentration factor (CF) were evaluated for five VFAs. The water flux and RSF were higher at a higher pH, temperature and in AL-DS mode. A low rejection rate of 23-36% and a CF of 0.20-1.90 were observed at a pH below the pKa due to the solubility of molecular VFAs, while rejection rates was 80-97% and concentration increase by 1 to 4.8-fold at a pH above the pKa values were achieved due to deprotonation of VFAs and changes in membrane surface charges. With an equal increase in temperature of FS and DS from 20 to 40°C, the rejection rate decreased by almost 20%. While with a transmembrane temperature change, a decrease in rejection rate of 20% was observed compared with baseline experiments due to decreases in viscosity and high diffusivity. In AL-DS mode, VFAs were rejected at a rate of almost 20% lower than that in AL-FS mode due to internal concentration polarization and membrane properties. These findings provide useful information on the factors that can influence optimal recovery rates of VFAs.

Osmotically assisted reverse osmosis, simulated to achieve high solute concentrations, at low energy consumption

Microbial electrosynthesis (MES), is an emerging technology, for sustainable wastewater treatment. The dilute acetate solution, produced via MES, must be recovered, as dilute solutions can be expensive to store and transport. The acetate is expensive and environmentally damaging to recover by heat-intensive evaporative methods, such as distillation. In pursuit of a better energy economy, a membrane separation system is simulated to raise the concentration from 1 to 30 wt%, at a hydraulic pressure of approximately 50 bar. The concentrate is then simulated to be heat dried. Reverse osmosis (RO) could rase the acetate concentration to 8 wt%. A novel adaptation of osmotically assisted reverse osmosis (OARO) is then simulated to increase the concentration from 8 to 30 wt%. The inclusion of OARO, rather than a standalone RO unit, reduces the total heat and electric power requirement by a factor of 4.3. It adds to the membrane area requirement by a factor of 6. The OARO simulations are conducted by the internal concentration polarisation (ICP) model. Before the model is used, it is fitted to OARO experimental data, obtained from the literature. Membrane structure number of 701 µm and permeability coefficient of 2.51 L/m2/h/bar are ascertained from this model fitting exercise.

Performance and implications of forward osmosis-membrane distillation hybrid system for simultaneous treatment of different real produced water streams

This study investigates the simultaneous treatment of different real produced water streams using forward osmosis-membrane distillation (FO-MD) hybrid system. The water–oil separator outlet (WO) was used simultaneously as FO draw solution (DS) and MD feed solution (FS). The FO process generated stable average fluxes of 13.6 L/m2/h and 15.8 L/m2/h with desalter effluent (DE) and wash water (WW) as FO feed streams, while MD produced 13.2 L/m2/h and 11 L/m2/h, respectively. Monovalent ions induced internal concentration polarization and CaSiO3 colloidal scaling on the support layer reduced the FO flux. Further FO flux reduction was caused by CaSO4 and NaCl crystals on the active layer. Moreover, CaSO4 created partial pore covering while oil and grease depicted pore clogging of the MD membrane, which decreased the MD flux. Volatile fatty acids and organic nano pollutants reached MD permeate and FO FS. Humic acid scaling was fully recovered by ethylenediaminetetraacetic acid by masking calcium ions and reducing the pH. No membrane wetting was observed in the system. No bacteria were found in real streams as analyzed with Epifluorescence microscopy, eliminating the potential of microbial fouling. The hybrid system showed > 93 % removal of oil, inorganics and organics, making the permeate quality excellent for re-injection or industrial reuse. The FS streams were concentrated by 77–84 % resulting in smaller disposal volumes. No utilization of chemicals and water makes this hybrid concept practical and sustainable. The findings of this study can serve as design criteria for future onsite pilot plant applications.

Taking advantage of large water-unstable Zn4O(BDC)3 nanoparticles for fabricating the PMM-based TFC FO membrane with improved water flux in desalination process

Developing the forward osmosis (FO) membranes to enhance their efficiency is of great importance as this technology is an important option to overcome water scarcity. In the present study, the water-unstable Zn4O(BDC)3 (where BDC = 1,4-benzodicarboxylate) nanoparticles of different sizes were embedded into the polyethersulfone (PES) matrix to form the porous-matrix membranes (PMMs) as the support layers in the forward osmosis FO thin-film composite (TFC) membranes. The main idea of this approach is to suppress the negative effect of the dilutive internal concentration polarization (DICP) in the FO mode by increasing the mean pore size and porosity of the support layer of the TFC FO membranes, leading to an enhanced FO water flux. According to the results, the water flux (Jw) increased from 26 L/m2.h in the pristine membrane (TFC-C) to 34 L/m2.h in the TFC-MOF-2 membrane fabricated with the large size Zn4O(BDC)3 nanoparticles (108 nm particle size and 2 wt. % loadings). Also, this membrane was used for the Caspian seawater desalination, and the water flux of 28.10 L/m2h (18.72 for the TFC-C) and the water flux reduction of 6 % (18.48 % for the TFC-C) during the long-term experiment were obtained.

Synergistic effect of highly porous microstructured support and co-solvent assisted interfacial polymerization on the performance of thin-film composite FO membranes

Internal concentration polarization (ICP) in a dense support layer is one of the main reasons holding back forward osmosis (FO) process. In this regard, a highly porous microstructured support (HPμS) featuring a quasi-sponge-free sublayer pore structure can be considered a suitable alternative to develop high-performance FO membranes. However, it has not been tested for its effects on FO. This study demonstrates that a TFC membrane prepared using the HPμS works out for FO by inducing 3.35 times higher water flux without compromising a reverse salt flux (Js) compared to a control TFC membrane prepared without support adjustment. The performance improvement could be achieved by HPμS's almost no sponge-like region and lateral walls, which were desirable to minimize ICP. Furthermore, we verified that it is possible to leverage co-solvent assisted interfacial polymerization (CAIP) to further improve FO membrane performances by creating a more permeable active layer. The in-house TFC membrane optimized by the HPμS and CAIP displayed 5.3 times higher FO water flux than the control membrane, while keeping comparable Js. We expect that this research could contribute to kicking the FO membrane performance up a notch by providing a practical example of simultaneous optimization of both support and active layers.

Real-time, dynamic monitoring of selectively driven ion-concentration polarization

Selective ion extraction is a vital element of many resource recovery systems. Carrier-based membranes offer the ability to remove specific, targeted ions from brine and waste streams, but these materials have delivered inconsistent outcomes in their active transport applications. To study non-ideal behaviors of target-ion selective membranes, we introduce a direct, real-time system for selectively measuring concentrations within electro-membrane boundary layers. In a carrier-based membrane system, we applied our method to monitor adverse, current-limiting behaviors. During its operation, we detected loss of transport selectivity and counter-ion discharge. It provided sufficient evidence to identify the mechanism underlying these adverse, over-limiting effects—the internal concentration polarization of free-carrier. Our method may raise new prospects for direct experimental characterization of nonlinear transport phenomena in electro-membrane systems.

Super-hydrophilic nanofiber substrate supported forward osmosis membrane with less polyamide layer defects by polydopamine-graphene oxide modification for high salinity desulfurization wastewater desalination

Super-hydrophilic electrospun nanofiber as the substrate of a thinu film composite forward osmosis (eTFC-FO) membrane can improve the performance of the membrane by mitigating internal concentration polarization (ICP). However, polyamine (PA) layer defects easily formed on super-hydrophilic nanofiber substrate hinders its further performance improvement. To prevent PA from forming deep inside the pores of substrate and alleviate PA defects, polydopamine-graphene oxide (PDA-GO) was introduced to modify the interlayer and PA layer of eTFC-FO membrane. Results showed that PA layer defects can be alleviated by addition of PDA-GO in interlayer or PA layer, and the simultaneous addition of PDA-GO in interlayer and PA layer resulted in the least defective PA layer of the eTFC-FO membrane (eTFC0.5-0.125). Performance evaluation demonstrated that the eTFC0.5-0.125 had a high FO water flux of 54.0 LMH and excellent ion rejections (>98.0%) for desalination of a real high salinity desulfurization wastewater. Besides the PA defects alleviation, nanochannel of PDA-GO for water transport also contributed to the performance improvement, as well as the fast water and salts diffusion by super-hydrophilic nanofiber substrate. Thus, a high performance eTFC-FO membrane was prepared on super-hydrophilic nanofiber substrate and was able to be used for high salinity water desalination.

Preparation and characterization of double-skinned FO membranes: Comparative performance between nanofiber and phase conversion membranes as supporting layers

To address the internal concentration polarization (ICP) effect and membrane fouling problems of forward osmosis technology in pressure retarded osmosis (PRO) mode, another highly selective polyamide (PA) layer was introduced on the other side of the single-skinned forward osmosis (FO) membrane. Recently, a new symmetrical nanofiber support layer has shown excellent performance. For better proof, the nanofiber support layer and the phase inversion support layer were prepared separately in this study, respectively, and two double-skinned FO membranes were obtained via interfacial polymerization. By comparing various surface physicochemical properties of the nanofiber support layer and the phase inversion support layer, it can be seen that the double-skinned PA layer formed on the surface of the nanofiber support layer had better performance. The nanofiber double-skinned FO membrane showed water flux of 19.99 LMH when using 2 M NaCl and DI water as the draw and feed solution, much higher than that of the phase inversion double-skinned FO membrane. Furthermore, the anti-fouling performance of the nanofiber double-skinned FO membrane was also better than that of the phase inversion double-skinned FO membrane. This study pointed out a new direction for a double-skinned FO membrane with high permeability selectivity and provided a promising method for anti-membrane fouling.

Silicene nanosheets as support fillers for thin film composite forward osmosis membranes

Development of membranes with enhanced separation and transport properties remains crucial for the advancement of forward osmosis (FO). Herein, a novel thin film composite (TFC) FO membrane with silicene-loaded polysulfone support (SN) is reported. Silicene loading was varied to obtain different SNs grown with polyamide (PA) layers to afford TFC-SN FO membranes. Characterization results reveal that optimal silicene loading (0.25 wt%) produced the most porous and most hydrophilic SN0.25 with finger-like pore structures. Low silicene loading showed minimal impact, whereas, excessive addition resulted in aggregation which diminished its effect in SN. Meanwhile, silicene had no influence on PA layer formation as all TFC-SNs registered similar solute permeability coefficient B = 0.14–0.16 LMH. On the other hand, TFC-SN0.25 achieved the highest water permeability coefficient A = 1.56 LMH bar−1 attributable to the favorable properties of SN0.25. TFC-SN0.25 also exhibited the lowest structural parameter S = 334 μm, which explains its superior FO performance relative to other TFC-SNs. Results from FO runs indicate that internal concentration polarization was reduced by 27.5–33% in TFC-SN0.25 compared with the control (TFC-SN0). FO runs in simulated low salinity water and seawater feed highlight the potential of TFC-SN0.25 for desalination. The developed TFC-SN0.25 can be repeatedly used and deliver consistent Jv values. Overall findings demonstrate the benefits of silicene for improved performance of TFC FO membranes.