Reverse Salt Flux Research Articles

FO membrane fabricated by layer-by-layer interfacial polymerisation and grafted sulfonamide group for improving chlorine resistance and water permeability

This study presents a layer-by-layer interfacial polymerization approach to enhance the chlorine resistance and water permeability of thin-film composite (TFC) polyamide (PA) forward osmosis membranes. The PA film was prepared by self-polymerization using 3,5-Dihydroxybenzoic acid (DHBA) and trimesoyl chloride (TMC) with addition of 4-amino-benzene sulfonamide (4-ABSA), which is a sulfonamide monomer, on a polysulfone (PSF) support layer. The cross-linking structure and surface characterisation of the DHBA-ABSA membrane was studied systematically. FTIR results showed the successful grafting of the sulfonamide group on the membrane surface. Compared with the MPD-TMC membrane, the water flux of three modified membranes—DHBA, ABSA, and DHBA with ABSA—improved by 27.6%, 44.0%, and 67.6%, respectively, and reverse salt flux decreased by 9.9%, 12.3%, and 16.2%, respectively. Furthermore, the chlorine-stability test using 200 ppm NaClO indicated stable long-term performance under different pH values. The stable sulfonamide structure of ABSA with N-H group effectively prevented chlorine from directly attacking the active layer and improve the chlorine-stability of the membrane. In addition, the abundant hydrophilic groups on ABSA and DHBA monomers formed a hydration layer with water molecules on the membrane surface through hydrogen bonding, which enhanced the permeability of the TFC-PA membranes. The findings of this study demonstrate the DHBA-ABSA membrane's wider application potential in water and wastewater treatment processes.

Synthesis of poly (vinylidene fluoride)/polyacrylonitrile electrospun substrate-based thin-film composite membranes for desalination by forward osmosis process

As a water treatment process that has the potential to require low energy inputs, forward osmosis (FO) has experienced a significant breakthrough in recent decades, particularly in membrane development. This paper focuses on blending poly (vinylidene fluoride) (PVDF) with hydrophilic polyacrylonitrile (PAN) to form PVDF/PAN substrates for thin film composite membranes (TFC). The membranes were characterized using a scanning electron microscopy, iS50 FTIR spectrometer, and contact angle system. With high porosity, low tortuosity, and interconnected hydrophilic pores of their substrates, the obtained TFC membranes showed high water fluxes. These membranes yielded superior water and reverse salt fluxes in FO tests compared to the commercial CTA membrane. The membranes also showed excellent mechanical performance under PRO test conditions.

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.

A freestanding graphene oxide framework membrane for forward osmosis: Separation performance and transport mechanistic insights

Graphene oxide (GO)-based membranes have been explored for application in forward osmosis (FO). However, the mass transfer inside GO framework membranes is far from sufficiently understood, and designing freestanding GO framework membranes with further enhanced performance remains a challenge. In this study, freestanding GO framework membranes were synthesized and investigated in a FO system. The membrane water flux, reverse salt flux, and forward salt flux were systematically investigated using different feed and draw solutions. The membrane synthesized using GO nanosheets and polyelectrolyte spacers (poly(sodium 4-styrenesulfonate) (PSS) (GO-PSS membrane) possesses high water flux, low reverse and forward salt flux, and low specific reverse salt flux (i.e., high water/salt selectivity). We found that both the size and surface charge density of the membrane pores influenced the salt transport inside the membrane in FO. By combining results from experiments and numerical modeling, the influence of the electrical double layer (EDL) extension inside the membrane pores on salt transport was quantitatively analyzed. Additionally, it was found that the EDL extension can influence the forward and reverse solute transport simultaneously (i.e., bidirectional transport). Furthermore, viable strategies toward designing GO framework membranes with enhanced performance for application in FO as well as their potential application niche were discussed.

The fouling layers characteristics of osmotically driven membranes affect transport behaviors of reverse salt permeation and per-fluorinated compounds

Perfluorinated compounds (PFCs) adversely affect the environment in very small amounts and are extremely stable substances. This study investigated the transport phenomenon of PFCs in terms of functional groups and membrane fouling types using 10 types of PFCs and evaluated the performance of osmotically driven membranes. The experimental results confirmed that the reverse salt flux (RSF) of organic fouled membranes significantly decreased (16.2 % and 22.3 %, respectively) and the relatively loosely deposited MP fouled membranes with many empty spaces in the fouling layers maintained RSF values similar to those of virgin membranes (2 % decreased). The rejection rates of the PFCs with SO3H functional groups increased (virgin: 96.8 %; fouled: 98.6 %), whereas PFCs with COOH functional groups decreased after organic matter fouling (virgin: 99.5 %; fouled 97.6 %). The micelles formation by PFCs with SO3H group was easily blocking fouling layers and intra-particle diffusion of other PFCs with SO3H molecules interrupt. PFCs having high Kow values tends to have increased removal efficiency after the formation of MP fouling layer. These results demonstrated that the membrane fouling layers play positive roles in the RSF and PFCs removal efficiencies in osmotically driven membrane processes, which will enable the securing of safe water resources.

Novel Thin-Film nanocomposite hollow fiber membranes in modules with reduced reverse solute flux for pressure retarded osmosis

Osmotic energy is released when mixing solutions with different salinities. Pressure retarded osmosis (PRO) is a promising membrane technology to harvest this osmotic energy. However, the current polymeric PRO membranes suffer from the high reverse solute fluxes during PRO processes, which would dramatically diminish the membrane performance, especially in big membrane modules. In order to control the reverse solute flux, two cup-like calix[n]arenes, sulfocalix[4]arene (SCA4) and sulfothiacalix[4]arene (STCAss) were incorporated into the polyamide network to enhance the PRO performance of thin-film nanocomposite (TFN) hollow fiber membranes in 1-inch modules. Due to the unique structures and the enhanced molecular-sieving abilities of both macrocyclic molecules, they were able to effectively improve the selectivity of the resultant TFN hollow fiber membranes. After optimizing the concentration of each nano-filler, it was found that the TFN membrane with 0.20 wt% of STCAss produced a PRO power density of 15.0 W/m2 and a reverse salt flux of 28.3 gMH, while the other containing 0.10 wt% of SCA4 produced a PRO power density of 14.2 W/m2 and a reverse salt flux of 31.6 gMH. In long-term PRO tests at 20 bar, the SCA4-incorporated membrane was more efficient in controlling the concentration polarization (CP) and maintaining the power density comparing to the STCAss membrane because the former has a smaller cavity opening than the latter. This research work may provide useful insights to further design PRO membranes and membrane modules for osmotic power generation.

UiO-66-NH2 nanocomposites incorporated cellulose acetate for forward osmosis membranes of high desalination performance

ABSTRACT In this paper, the hydrophilic UiO-66-NH2 nanomaterial was synthesized by the solvent-thermal method and characterized. Then, UiO-66-NH2 was introduced into the casting membrane solution of cellulose acetate (CA) forward osmosis (FO) membrane, and CA/UiO-66-NH2 forward osmosis membrane was prepared by the phase inversion method. The optimum preparation conditions of CA/UiO-66-NH2 mixed matrix membranes were determined as follows: the content of UiO-66-NH2 was 0.4 wt%, the coagulation bath temperature was 35°C, the mixing temperature was 50°C and the heat treatment temperature was 50°C. FTIR, SEM, water contact angle and AFM were carried out on CA/UiO-66-NH2 forward osmosis membrane prepared under the best preparation conditions. Compared to the CA forward osmosis membrane, the permeability and selectivity of the CA/UiO-66-NH2 membrane were improved. The water flux and reverse salt flux of the CA/UiO-66-NH2 forward osmosis membrane reached 52.32 L/(m2·h) and 2.43 g/(m2·h), respectively. The permeability selectivity of CA membranes and CA/UiO-66-NH2 membranes did not change much during 180 min, indicating that the two membranes had good long-term stability. This study shows a potential advantage of UiO-66-NH2 as additives for improvement in the desalination performance of forward osmosis membranes.

Fabrication and characterization of inner selective antibiofouling forward osmosis hollow fiber membranes for simultaneous wastewater treatment and desalination

Forward osmosis (FO) hollow-fiber membranes were prepared by in situ thin layer assembly of polyethyleneimine (PEI) on antifouling PES-based porous nanocomposite membranes during membrane formation by spinning and phase inversion, via incorporation of surface-modified silver nanoparticles (NPs) in the dope solution and addition of PEI in the bore liquid; after cross-linking with glutaraldehyde the FO selective layer was obtained at the lumen surface while the shell surface had ultrafilter (UF) properties. This design enabled the utilization of the FO membranes in active layer facing draw solution (DS) orientation to employ maximum effective osmotic pressure, while the UF layer in combination with the antibacterial NPs was supposed to reduce fouling by the wastewater used as feed solution (FS). The quality of the active layer assembly was characterized using atomic force microscopy and scanning electron microscopy analyses, as well as salt rejection, structural parameter (S), and molecular weight cut-off (MWCO) measurements. The separation performance of these membranes was evaluated in an osmotic membrane bioreactor (OMBR) system, showing for the best FO nanocomposite membranes less than 10% fouling and flux reduction over 5 cycles of operation over a total period of 5 days. The best-suited membrane showed promising separation performance in the OMBR system by providing 43.4 LMH water flux and only around 0.2 g/l specific reverse salt flux (SRSF) with 1 M NaCl and DI water serving as DS and feed, respectively. This study focused also on distinctive performance criteria in combined FO and OMBR systems, such as the membrane’s potential in a pretreatment step of brine streams (used as DS) to provide proper feed composition for RO units and introduced a new specific performance index (SPI) for better characterization of FO membranes which summarizes all essential characteristics of the membrane application, instead of using existing structural parameter equations for membrane characterization. The best-suited FO membrane offered an SPI of 778.2 gl−1 m−2 h−1, meaning 778.2 g/l reduction of TDS in DS per unit membrane surface area per hour.

Electrically charged forward osmosis: Promoting reverse salt flux to enhance water recovery and struvite precipitation

Agricultural wastewater contains high concentrations of nitrogen and phosphorus. There is a growing interest in recovering these nutrients. In this study, an electrically charged forward osmosis (eFO) system was developed to recover struvite and water from synthetic livestock wastewater. By applying a voltage near the surface of the FO membrane, magnesium migrated reversely into the feed chamber and reacted with the ammonium and phosphate in the feed solution to form struvite. As a result of electrical charging, the recovery of struvite and water was enhanced by 77% and 39%, respectively. The enhancement might be because dilutive and concentrative polarization was alleviated on the draw and feed side of the FO membrane during ion migration. High external voltage, high draw concentration, and alkaline/neutral draw pH favored water recovery and struvite precipitation. This study provides insights into harnessing reverse salt flux to improve the recovery of nutrients and water in FO systems.

Fabrication of dialyzer membrane-based forward osmosis modules via vacuum-assisted interfacial polymerization for the preparation of dialysate

Direct preparation of dialysate from tap water based on osmotic dilution is beneficial for home hemodialysis which requires a defect-free forward osmosis (FO) membrane module. This report introduced a new vacuum-assisted interfacial polymerization (VAIP) process for optimal distribution of the aqueous phase and a well-controlled IP using dialyzer membranes. We demonstrated statistically that the vacuum-assisted process is beneficial for the preparation of integral FO modules with multiple fine fibers due to the good distribution of the aqueous phase. The as-prepared FO module displayed a low structural parameter (262 μm), an acceptable water flux (17.6 L m−2 h−1), and a low specific reverse salt flux (0.16 g/L) using deionized (DI) water as the feed and 1 M NaCl as the draw in AL-FS mode. Direct dialysate preparation from tap water using the FO module was presented and modeled with a good fit. The work showcases a new FO module based on dialyzer and its potential applications in the medical field.

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.

Coupling solar-driven interfacial evaporation with forward osmosis for continuous water treatment.

Forward osmosis (FO) driven by osmotic pressure difference has great potential in water treatment. However, it remains a challenge to maintain a steady water flux at continuous operation. Herein, a FO and photothermal evaporation (PE) coupling system (FO-PE) based on high-performance polyamide FO membrane and photothermal polypyrrole nano-sponge (PPy/sponge) is developed for continuous FO separation with a steady water flux. The PE unit with a photothermal PPy/sponge floating on the surface of draw solution (DS) can continuously in situ concentrate DS by solar-driven interfacial water evaporation, which effectively offsets the dilution effect due to the injected water from FO unit. A good balance between the permeated water in FO and the evaporated water in PE can be established by coordinately regulating the initial concentration of DS and light intensity. As a consequence, the polyamide FO membrane exhibits a steady water flux of 11.7 L m-2 h-1 over time under FO coupling PE condition, effectively alleviating the decline in water flux under FO alone. Additionally, it shows a low reverse salt flux of 3g m-2 h-1. The FO-PE coupling system utilizing clean and renewable solar energy to achieve a continuous FO separation is significantly meaningful for practical applications.

Preparation and characterization of novel thin film composite forward osmosis membrane with halloysite nanotube interlayer

In this study, the electrospun polyacrylonitrile (ePAN) fiber mats were used as support layer and natural mineral-halloysite nanotubes (HNTs) was used to construct the interlayer. Polydopamine modification was utilized to enhance the hydrophilicity of ePAN substrates and dispersibility of HNTs. The mHNTs interlayer effectively minified the surface pore size of substrates providing a better interface for interfacial polymerization forming an integrated and thin PA selective layers. Compared to the unmodified membranes, the water flux of the optimized membrane with mHNTs interlayer about 61.60% and 79.70% higher and the reverse salt flux of which was 38.95% and 45.08% lower in AL-FS mode and AL-DS mode respectively. These results suggested that introducing halloysite nanotube interlayer is an effective, and low-cost way to fabricate high-performance FO membrane. ● Highly accessible and low-cost halloysite nanotubes (HNTs) were utilized to construct interlayers on electrospun nanofiber substrates. ● A high-performance thin film composite forward osmosis membrane was successfully prepared. ● HNTs interlayer showed benefits in generation of polyamide selective layers in interfacial polymerization. ● High water flux and low reverse salt flux were observed synchronously.

Quantitatively relating the structural performance of polyamide layer with skin layer modified via in-situ precipitation

How the structure of skin layer determines the structure of incipient film and final membrane formed during interfacial polymerization is decisive for polyamide composite membranes but difficult to monitor. This work introduced a methodology to predict an estimated initial molar ratio between monomers (η) via introducing pore diameter (dp), porosity (εSkin), tortuosity (τSkin), and thickness (lSkin) of skin layer to Fick's diffusion law to correct flux of monomers. The structure of skin layer was regulated via in-situ preparation of sacrificial precipitation. With characterized parameters of dp = 25.91 nm, εSkin = 8.32%, τSkin = 7.41, and lSkin = 260 nm, η was 4.25. The resultant forward osmosis membrane exhibited flux of 58.83 ± 3.58 L/(m2·h) and reverse salt flux of 10.68 ± 2.38 g/(m2·h) under AL-DS mode with 1.0 mol/L NaCl and DI as draw and feed solution, respectively, which had broken historical upper boundary. The proposed methodology can make quantitative prediction for the structural performance of polyamide composite membranes.

A novel highly osmotic K/Fe3O4/CNF magnetic draw solution for salty water desalination

Forward osmosis (FO) is increasingly being studied as an alternative desalination technique to the other conventional desalination technologies, owing primarily to its low energy potential. However, the co-opted energy limitations in the draw solution (DS) regeneration stage in FO desalination processes and the lack of effective DS have hampered FO's implementation for potable water application on an industrial scale. In this work, we explored the Donnan principle to engineer a DS material having the duality of magnetic and solar-thermal separability functionalities from a sustainability viewpoint whilst exploiting a careful selection of material properties. A novel potassium functionalised iron oxide doped carbon nanofibres (K/Fe3O4/CNF) magnetic nanoparticles (MNPs) was successfully synthesised for FO desalination applications, utilising an eco-friendly strategy that improves hydrophilicity of DS without polymers. The novel DS obtained a significant osmotic pressure (86.1 bar), whilst it FO performance showed a small reverse salt flux (RSF) and specific reverse salt flux (SRSF) values of 0.10 gMH and 0.004 g/L, respectively. These values compare to at least <10 % of most RSF and SRSF values reported in the literature. The facile DS synthesis strategy adopted herein will potentially open a new route to preparing other DS nanomaterials with unique multi functionalities and enhanced hydrophilicity devoid of polymers. Whilst magnetic DS re-concentration may be achievable, additional research is required to appraise this methodology's overall energy implications and economic advantages over existing DS recovery methods.

Enhancing interfacial interaction of PDMS matrix with ZIF-8 via embedding TiO2@ZIF-8 composites for phenol extraction in aqueous-aqueous membrane extractive process

The presence of phenol as an organic pollutant in industrial effluents is the biggest threat to the aquatic environment and human health. The aqueous-aqueous extraction process is an attractive method to treat saline phenolic wastewater (feed solution) via diffusion through a semi-permeable polydimethylsiloxane (PDMS) to the receiving solution. To improve the value of mass transfer coefficient, thinning the PDMS layer and embedding it with nanoparticles/metal-organic frameworks (MOFs) can lead to membrane defects or weakened mechanical strength, which is not promising for large-scale practical applications. Therefore, herein, an interfacial design strategy is demonstrated to disperse TiO2@ZIF-8 composites as hybrid particles into the top selective layer (PDMS) of TFC (thin-film composite) membrane to enhance polymer-filler compatibility and mass transfer coefficient. The TiO2@ZIF-8 composites enhanced the affinity to the polymer matrix, thereby increasing the mechanical stability and preventing interfacial voids and agglomeration. Moreover, the TiO2@ZIF-8 incorporated TFC membranes exhibited an enhanced mass transfer coefficient (ko) of (25.28 ± 0.5) × 10−7 and a reduced reverse salt flux of 9.5 mg/m2.h. The enhanced mechanical stability and mass transfer coefficient were attributed to the synergistic effect provided by TiO2@ZIF-8 composites, as ZIF-8 particles provided continuous pathways (pore-flow mode) and TiO2 nanoparticles provided compactivity with PDMS. The synergistic effects of hybrid particles could provide a new strategy to develop PDMS for the extraction of various organic compounds.

Performance of pilot-scale constructed wetland osmotic microbial fuel cell under different gravel conditions.

This paper explores the performance of pilot-scale constructed wetland osmotic microbial fuel cell (CW-OMFC) in different gravel conditions. The performance was measured in terms of power generation, water flux, chemical oxygen demand (COD) removal, and coulombic efficiency. The CW-OMFC was divided into four sections based on the porosity of the materials. The surface area of materials at Side A, Side B, Side C, and Side D were 2.717 m2.g-1, 0.228 m2.g-1, 0.095 m2.g-1, and 0.072 m2.g-1, respectively. The CW-OMFC achieved maximum water flux, minimum reverse salt flux, high power density, and COD removal efficiency of 6.66 ± 0.5 L.m-2.h-1, 3.33 ± 1.2g.m-2.h-1, 59.53 ± 10 mW.m-2 and 84.69%, respectively, by using high porous materials. The nutrients (nitrogen, phosphorus, and potassium) uptake by plants from wastewater were 12.17%, 12.01%, and 21.73%, respectively.

Apple Juice, Manure and Whey Concentration with Forward Osmosis Using Electrospun Supported Thin-Film Composite Membranes.

Forward osmosis (FO), using the osmotic pressure difference over a membrane to remove water, can treat highly foul streams and can reach high concentration factors. In this work, electrospun TFC membranes with a very porous open support (porosity: 82.3%; mean flow pore size: 2.9 µm), a dense PA-separating layer (thickness: 0.63 µm) covalently attached to the support and, at 0.29 g/L, having a very low specific reverse salt flux (4 to 12 times lower than commercial membranes) are developed, and their FO performance for the concentration of apple juice, manure and whey is evaluated. Apple juice is a low-fouling feed. Manure concentration fouls the membrane, but this results in only a small decrease in overall water flux. Whey concentration results in instantaneous, very severe fouling and flux decline (especially at high DS concentrations) due to protein salting-out effects in the boundary layer of the membrane, causing a high drag force resulting in lower water flux. For all streams, concentration factors of approximately two can be obtained, which is realistic for industrial applications.

Treatment of textile industry wastewater by using high-performance forward osmosis membrane tailored with alpha-manganese dioxide nanoparticles for fertigation.

Forward osmosis (FO) technology has been acknowledged as an energy-efficient cutting-edge water treatment innovation; however, the inefficient performance of polymer-based membranes remains a tailback in the practical utilization of FO. A significant issue in FO is membrane fouling, which negatively influences the flux efficiency, working expenses and membrane life expectancy. Membranes having high water flux and minimum reverse solute flux at low operating pressures are the ideal membranes for this process. This study reports a thin-film nanocomposite (TFNC) membrane for the treatment of textile industry wastewater utilizing fertilizer as draw solution fabricated via the phase inversion process. The chemical structure and morphology of the synthesized manganese oxide (MnO2) incorporated membrane were studied by various characterization techniques like X-ray diffraction, Fourier transform infrared spectroscopy, scanning electron microscopy-energy-dispersive X-ray spectroscopy, contact angle and gravimetry. The outcomes demonstrated that the nanoparticles were bonded to cellulose acetate polymer via covalent bonds and showed very hydrophilic membrane surface, along with an increased osmotic water flux of 52.5 L.m2.h-1 and reverse salt flux of 10.9g.m2.h-1, when deionized wastewater and potassium chloride were used as the feed solution and the draw solution, respectively. In this manner, incorporating manganese oxide into the FO membrane may introduce its extraordinary possible application for the production of diluted fertilizer solution with balanced nutrients.