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Blind source separation (BSS) is a critical task in untangling non-stationary signals without prior information. This paper extensively explores diverse time-frequency analysis (TFA) methods within BSS systems over the past decade. It underscores the pivotal role of TFA in dealing with non-stationary signals by characterizing their attributes across time and frequency domains. This approach provides a comprehensive understanding of signal dynamics that surpasses conventional techniques focusing solely on temporal or spectral domains. The paper delves into various TFA methods, investigating their influencing factors and aiding researchers in selecting relevant techniques aligned with their objectives. Furthermore, it comprehensively reviews contemporary research, categorizing BSS algorithms into three classes. The role of commonly used TFA methods in each class is systematically evaluated, identifying their strengths and limitations during different separation stages. The paper addresses challenges in implementing BSS algorithms, particularly in under-determined systems with fewer mixing channels than source signals. It highlights the central role of TFA in overcoming these challenges and enhancing separation outcomes.

The demand for carbon dioxide (CO2) emission mitigation has driven the scientific community to develop a viable strategy. Gas separation technology are considered as the most promising and effective carbon capture approach. The utility of mixed-matrix membranes (MMMs) for selective gas separation has prompted a paradigm shift from conventional methods towards more efficient and sustainable processes. Metal-organic frameworks (MOFs), with high porosity, surface area, and structural tunability, are identified as suitable fillers in MMMs. Their application in carbon capture and gas separation processes could significantly reduce greenhouse gas emissions while maintain cost-effectiveness. Herein, this review presents the latest scientific and technological advancements in several types of representative MOF fillers, including Zeolitic Imidazolate Frameworks (ZIFs), Materials of Institute Lavoisier (MILs), University of Oslo (UiO), and Hong Kong University of Science and Technology (HKUST-1). It also highlights the current challenges associated with MOF fillers and outlines potential research opportunities for future improvements in the performance of MOF-based MMMs.

Purpose: All secondary dispersal by wind, important for predicting, modeling and regulating diaspore dispersal processes, and for biodiversity conservation and vegetation restoration, is influenced by underlying surface matrix. But little is known about how matrix determines diaspore secondary dispersal. Here we focus on how lift-off velocity, good proxy for secondary dispersal of seeds by wind, is linked to the underlying surface matrix. Methods: We investigated the effect of the underlying surface matrix on diaspore lift-off velocity in a wind tunnel. Our study used 11 matrix types with different particle size, including four pure substrates (loam, aeolian sand, river sand, gravel) and seven mixtures thereof and diaspores of 28 species differing in length, width, height, mass, projected area, shape index, wing loading, and terminal velocity. Results: Diaspores were more easily dispersed from loam, aeolian sand and river sand than from the gravel substrates. For mixed matrices, lift-off velocity was closer to that of the small-sized than of the large-sized component of the substrate. Underlying surface matrix contributed more to diaspore dispersal by wind than diaspore attributes. In addition to wing loading, terminal velocity, and projected area also were important diaspore attributes determining lift-off velocity of the diaspores. Conclusion: Lift-off velocity of diaspores is influenced by particle size of underlying surface matrix during secondary wind dispersal: lift-off velocity is the largest on large-sized particles for pure matrices, and determined by the small-sized component for mixed matrices. [ABSTRACT FROM AUTHOR]

Nowadays, effective removal of dye and salt from aqueous solutions has received widespread attention in the field of wastewater treatment. In this study, Zr-based nanofillers were used to create high-flux polyethersulfone nanofiltration membranes with impressive anti-fouling performance. Three different levels of UiO-66-NH 2 concentration (0.01, 0.1, 1 wt%) were used in membrane body. Solvothermal method was used to synthesize the nanoparticles, and their physical and chemical characteristics were examined through FTIR, XRD, EDAX, and FESEM analyses. Membranes properties also were investigated by SEM, porosity, water content, roughness, water contact angle, flux, separation efficiency, and fouling studies. The surface roughness of the blended membrane with 0.01 wt% nanoparticles (M2) was almost halved compared to the pristine membrane (M1). The water contact angle was also reduced from 70.98° for M1 to 39.09° for M2. The water flux of M2 with 0.01 wt% nanoparticles was 2.31 times higher than that of the pristine membrane. The MB, RhB, and RB21 dyes, as well as Na 2 SO 4 , MgSO 4 , MgCl 2 , and NaCl solutions, were used to investigate the membrane separation efficiency. All modified membranes showed significant dye retention for both cationic and anionic dyes, and sodium sulfate rejection reached up to> 93.2%. The M2 exhibited the best performance for removal of MB (95.8%), RhB (94.2%), and RB21 (83.6%). The FRR was 46.51% for bare membrane, whereas it was increased significantly for the modified samples up to> 86%. The total resistance of the optimal membrane was remarkably reduced compared to the PES pristine membrane. • High-performance NF-membrane prepared by incorporating of aminated Zr-based MOF. • Results showed uniform and more compatible structure for synthesized MOF. • High surface wettability and permeability obtained for composite membranes. • Blended membranes showed high ability for dye and salt removal from water. • Mixed matrix membranes exhibited superior antifouling ability & FRR. [ABSTRACT FROM AUTHOR]

【Objective】The present paper aimed to promote the effective utilization of agricultural waste resources, to find suitable materials to replace peat and reduce the damage of waste to local ecology, the mixed matrix with different proportions of cattle manure and mushroom residue adding vermiculate and perlite was made to investigate the effects of mixed matrix on the properties, the growth of cucumber seedling and cost.【Method】A total of 7 treatments were set up, in which vermiculite and perlite each accounted for 10% by volume, mushroom residue and cattle manure accounted for 80% totally by volume, and the volume ratio of mushroom residue to cattle manure of T1-T7 were 1∶7, 2∶6, 3∶5, 4∶4, 5∶3, 6∶2 and 7∶1, using commercial substrate as contrast, the seedlings were randomly distributed and each treatment was repeated 3 times.【Result】 The physicochemical properties of the mixed matrix differed with the mushroom residue to cattle manure ratio, but all were in the suitable range of cucumber seedling growth.With the decreasing of cattle manure content and the increasing of mushroom residue content, the permeability, gas to water ratio and pH of the substrate increased, and the EC value decreased, and the contents of nitrogen, phosphorus and potassium increased firstly and then decreased; The stem diameter, dry weight and fresh weight of underground and root-shoot ratio of seedlings, root activity and chlorophyll content of seedlings increased significantly on the mixed matrix T1-T7.It saved 20-80 yuan per ton for mixed matrix of different proportions comparing with commercial substrate.【Conclusion】The results of grey relational analysis shows that T6-T7 ware more suitable for cucumber seedling cultivation, which can lay a foundation for rational utilization of agricultural waste, and help reduce the use of non-renewable resources such as peat. [ABSTRACT FROM AUTHOR]

This review article presents an extensive study on ammonia elimination from wastewater through membrane separation technology. The mechanism, performance and morphology of different types of membranes that have been employed for ammonia removal from wastewater such as hollow fiber membrane contactor, membrane distillation contactor and flat sheet membranes including blend, and mixed matrix membranes were analyzed. The impact of various variables, for example feed solution pH, concentration of ammonia in the feed solution, operation temperature, membrane thickness, the feed velocity and striping phase velocity on ammonia removal performance of membranes, was evaluated. To summarize the experimental studies, the best performance of membranes reported in the articles was compared and the future perspective of ammonia removal by membrane technology was reported. [ABSTRACT FROM AUTHOR]

• New (PES-CoFe 2 O 4 /AC) membrane was prepared using phase inversion method. • Surface hydrophilicity & antifouling ability of blended membranes enhanced obviously. • (PES-CoFe 2 O 4 /AC) membrane showed high permeability and more stable flux. • Na 2 SO 4 & NaCl rejections raised from 55%, 42% for PES membrane to 95%, 85% for MMM. • Pb, Ni & Cu rejections measured 86, 90 & 97% for (PES-CoFe 2 O 4 /AC) membrane. In this study, a mixed matrix polyethersulfone-based nanofiltration membrane was prepared by incorporation of (cobalt ferrite/activated carbon) composite nanoparticles. The composite nanoparticles were also synthesized using the chemical precipitation technique. The FTIR, XRD and FESEM were used to characterize the synthesized nanoparticles. The fabricated membranes were also studied using SEM, 3D surface image, and water contact angle, mean pore size and porosity measurements. The water flux, salt rejection and antifouling ability of membranes were investigated. The blended membranes showed a more hydrophilic and smoother surface compared to the pristine membrane. The membrane PWF was declined initially using 0.05 wt. % (CoFe 2 O 4 /AC) nanoparticles into membrane body and then enhanced by a further increase of nanoparticles' concentration up to 0.1 wt. % in membrane matrix; PWF was reduced again for the blended membranes at higher concentration of nanoparticles. The NaCl and Na 2 SO 4 rejections were enhanced from (42% to 85%) and (55% to 95%) by the use of (CoFe 2 O 4 /AC) nanoparticles into the membrane body. The blended membranes also exhibited appropriate anti-fouling property and more stable flux compared to the pristine membrane. The highest Pb2+, Ni2+, and Cu2+ rejections were found 86%, 90%, and 97%, respectively, for the blended membrane containing of 1 wt. % (CoFe 2 O 4 /AC) compared to others. [ABSTRACT FROM AUTHOR]

Subsurface wastewater infiltration systems (SWIS) are one of the important sources of nitrous oxide (N2O) production; understanding the biological processes and contributions of N2O will help control the amount of N2O produced. To quantitatively reveal the contribution of nitrification and denitrifiaction processes, 8 g potassium nitrate with 99.99 atom % 15N (i.e. 15N accounts for 99.99% of the total N) was dissolved in the influent (concentration: 3.3 g/L). Results showed that nitrification released more N2O within 0–12 h, accounting for 79.6 ± 2.4%. The denitrification process accounted for 88.5 ± 1.3% for N2O generation after the 12th hour. Thus, in order to effectively control the release of N2O, the denitrification process should be given more attention. The maximum release rate of N2O was 8.45 ± 0.8 mg/m2·h, which occurred near the end of the first wetting-drying cycle. Since then, peaks appeared periodically, mostly in the “rest” periods.

Polyvinylchloride (PVC) based heterogeneous cation exchange membranes were prepared by the solution casting technique. The effect of super activated carbon nanoparticles concentration as filler additive in membrane matrix on ionic transfer behaviors of the membrane was studied. SOM images showed uniform particles distribution and relatively uniform surfaces for the membranes. The membrane water content was improved initially by using of super activated carbon nanoparticles up to 0.5 %wt in the casting solution and then began to decrease by more increase of nanoparticles content ratios from 0.5 to 4 %wt. Utilizing of activated carbon nanoparticles in the casting solution also led to increase of water contact angle, membrane ion exchange capacity, fixed ionic concentration, membrane potential, transport number and membrane selectivity obviously.An Opposite trend was observed for the membrane electrical resistance. The sodium flux/permeability was also enhanced initially by increase of nanoparticles concentration up to 0.5 %wt and then decreased slightly by more increase of nanoparticles loading ratios from 0.5 to 1 %wt. The sodium flux was sharply enhanced again by more increase of nanoparticles concentration form 1 to 4 %wt. The membrane transport number and selectivity were increased initially by increase of electrolyte concentration and then showed decreasing trend. The membranes showed higher transport number and selectivity at neutral pH compared to other pH values. The ED results showed that dialytic rate of lead ions was increased by utilizing of super activated carbon nanoparticles in the membrane matrix.

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Polymeric membrane-based gas separation has found wide applications in industry, such as carbon capture, hydrogen recovery, natural gas sweetening, as well as oxygen enrichment. Commercial gas separation membranes are required to have high gas permeability and selectivity, while being cost-effective to process. Mixed matrix membranes (MMMs) have a composite structure that consists of polymers and fillers, therefore featuring the advantages of both materials. Much effort has been made to improve the gas separation performance of MMMs as well as general membrane properties, such as mechanical strength and thermal stability. This perspective describes potential use of MMMs for carbon capture applications, explores their limitations in fabrication and methods to overcome them, and addresses their performance under industry gas conditions. [ABSTRACT FROM AUTHOR]

This study investigates the efficacy of Fe3O4/PVP composite nanoparticles incorporating into heterogeneous cation exchange membranes on their physicochemical properties and desalination performance via electrodialysis. The blended membranes were fabricated through solution casting technique and characterized by scanning optical microscopy (SOM), scanning electron microscopy (SEM), Fourier transform infrared spectroscopy (FTIR), and energy-dispersive X-ray spectroscopy (EDX). The areal electrical resistance declined sharply from 14.7 (Ω cm2) for the pristine membrane to 5.8 (Ω cm2) for the Fe3O4/PVP embedded mixed matrix membranes, whereas the change in membrane water uptake was less that 4%. The blended membranes showed smoother and more hydrophilic surface compared to pristine membrane. The membrane potential, transport number, and permselectivity were also improved obviously by utilizing of Fe3O4/PVP nanoparticles. The nanocomposite membranes demonstrated good potential in separation of bi- to mono-valent ions (Ba2+/Na2+) which was ~ 2.1. [ABSTRACT FROM AUTHOR]

A new type of electrodialysis mixed matrix (MM) cation exchange membrane was prepared by incorporating carbon nanofibers (CNFs) into membrane matrix. The microscopy images showed uniform surface for the membrane relatively. The use of CNFs into membrane body enhanced membrane surface hydrophilicity, potential, transport number, permselectivity, and ionic conductivity obviously, while water uptake decreased. The sodium flux was also enhanced by incorporation of CNFs into membrane matrix from 0 to 0.5%wt and 2 to 8%wt, while declined for the samples in the range of 0.5 to 2%wt CNF ratios. Compared to pristine membrane, a smoother surface was observed for PVC-CNF membrane. Electrodialysis showed the (K+/Na+) flux ratio about 2.14. The transport mechanism of K+ and Na+ ions through the membranes discussed by considering ionic and hydrated radius, hydration potential, hydration free energy, entropy of hydration, and the Jones-Dole coefficient. Optimal performance was achieved for PVC-0.5%wt CNF membrane. [ABSTRACT FROM AUTHOR]

At present, most of the researches on protein classification are based on graph kernels. The essence of graph kernels is to extract the substructure and use the similarity of substructures as the kernel values. In this paper, we propose a novel graph kernel named vertex-edge similarity kernel (VES kernel) based on mixed matrix, the innovation point of which is taking the adjacency matrix of the graph as the sample vector of each vertex and calculating kernel values by finding the most similar vertex pair of two graphs. In addition, we combine the novel kernel with the neural network and the experimental results show that the combination is better than the existing advanced methods. [ABSTRACT FROM AUTHOR]

Electrodialysis-mixed matrix tris(8-hydroxyquinolinato)aluminum (AlQ3) nanoparticles entrapped heterogeneous cation-exchange membrane was prepared by the solution casting technique. The effect of the concentration of AlQ3 in the casting solution on the physico-chemical properties of the homemade membranes was studied. AlQ3 nanoparticles were synthesized via a simple precipitation method and characterized by scanning electron microscopy, Fourier-transform infrared spectroscopy, and X-ray diffraction. The use of AlQ3 nanoparticles in the membrane matrix led to an increase of the membrane electrical conductivity and surface hydrophilicity. The membrane ion-exchange capacity was enhanced by using AlQ3 loading ratios up to 1.5 wt%; the IEC decreased for concentrations above 1.5 wt%. The increase of AlQ3 content ratios up to 0.5 wt% in fabricated membrane initially caused to increase of water content. The membrane water content was decreased for the concentrations between 0.5 to 1.5 wt% and then showed an increasing trend again at higher additive loading ratios. The membrane potential, charge density, permselectivity, and transport number were improved obviously by the use of AlQ3 nanoparticles in membrane body. The ion flux/permeability enhanced sharply by using of AlQ3 up to 0.5 wt% in the membrane matrix and then began to decrease while the additive concentration was more than 0.5 wt%. [ABSTRACT FROM AUTHOR]

• Polymer selection has a key role in fabrication of multilayer composite membranes (MCM). • Optimization of MCMs structural configuration needed to produce defect-free membranes. • Aspen simulation demonstrated two-stage membrane model to control biomethane slip. • Economic analysis shows that the developed model is best fit for biomethane enrichment. The depletion of fossil fuels has led to the development of various biogas upgrading techniques that can be a reliable and sustainable energy source. At present, membrane-based gas separation and enrichment have received more acceptance to contend with the traditional biogas upgrading processes. Remarkably, multilayered composite membranes (MCM) fabricated from selective polymers and fillers have achieved high consideration in the field of CO 2 separation. In this regard, the present study focuses on fabricating and optimizing the porous layer of MCM using Polyether sulfone (PES) and Torlon polymers and their morphological influences on overall membrane performance. The MCM membranes fabricated from the PES porous substrate exhibited 3–4 fold higher permeation than the Torlon. Besides, the effect of zeolite type and % loading on the selective layer performance in CO 2 gas permeation was examined. From the gas permeation experiments, a 6 % loaded 3A zeolite sample exhibited maximum permeation flux for CO 2 , which is 1.7 folds compared to the neat Polyether block amide (PEBAX)/PES membrane and 5.8 fold to the neat PEBAX/Torlon without compromising the selectivity. Furthermore, process simulation using Aspen Hysys reveals the economic feasibility of membrane-based biomethane enrichment. Overall, the study results are compared with Robeson's plot, which reveal the substantial potential of MCM-based membrane technology as a biogas upgrading process and offers assistance in developing an appropriate porous support for MCM. [ABSTRACT FROM AUTHOR]

In this work, the performance of new robust mixed matrix composite hollow fiber (MMCHF) membranes with a different selective layer composition is evaluated in the absence and presence of water vapor in CO2/N2 and CO2/CH4 separation. The selective layer of these membranes is made of highly permeable hydrophobic poly(trimethyl-1-silylpropine) (PTMSP) and hydrophilic chitosan-ionic liquid (IL-CS) hybrid matrices, respectively, filled with hydrophilic zeolite 4A particles in the first case and HKUST-1 nanoparticles in the second, coated over compatible supports. The effect of water vapor in the feed or using a commercial hydrophobic PDMSXA-10 HF membrane has also been studied for comparison. Mixed gas separation experiments were performed at values of 0 and 50% relative humidity (RH) in the feed and varying CO2 concentration in N2 and CH4, respectively. The performance has been validated by a simple mathematical model considering the effect of temperature and relative humidity on membrane permeability.

Novel mixed-matrix electrodialysis heterogeneous ion exchange membranes were fabricated using polyaniline (PANI)-co-graphene oxide (GO) functionalized composite nanoplates. The PANI-co-GO functionalized composite nanoplates were prepared by in situ chemical oxidative polymerization of aniline in the presence of GO nanoplates. The synthesized PANI/GO were characterized by Fourier transform infrared spectroscopy, X-ray diffraction, and scanning electron microscopy. The SEM images demonstrated that utilizing of PANI/GO in membrane matrix led to formation of membranes with a compact structure. Also, more uniform distribution was observed for the incorporated PANI/GO membrane compared to the embedded GO nanoplates ones. The surface hydrophilicity, water content, and ion exchange capacity were enhanced by utilizing PANI/GO composite nanoplates. The membrane potential, transport number, and selectivity were also enhanced in sodium and barium chloride ionic solutions in presence of functionalized nanoplates. The newly prepared membranes showed lower selectivity and transport number for barium ions compared to sodium ions. The sodium and barium flux were enhanced by using PANI/GO. Dialytic rate results showed that modified membranes in this study have good ability in lead ion removal from wastewater. The enhancement in lead flux was more than 50% for the modified membrane containing PANI/GO in comparison with pristine ones. [ABSTRACT FROM AUTHOR]

Nanofilraion membranes (NF) were fabricated by an incorporation of CeO 2 /Ce 7 O 12 nanoparticles with various loads via phase inversion method. The prepared cerium oxide nanoparticles and fabricated mixed matrix membranes were recognized by using x-ray diffraction, Fourier transform infrared spectroscopy, scanning electron microscopy, surface charge studies and contact angle. The performances of the fabricated membranes were carried out using 100 mg/L/each aqueous solutions of Fe(NO 3 ) 3 , Al 2 (SO 4 ) 3 , Co(NO 3 ) 2 , Cd(NO 3 ) 2 , Cu(NO 3 ) 2 . The antifouling properties of the mixed matrix membranes were studied using 300 mg/L humic acid as foulant. The morphologies of the fabricated membranes have been affected by the presence of CeO 2 /Ce 7 O 12 nanoparticles, as fillers, in the casting solution. Since, the four mixed matrix fabricated membranes of different nanoparticles loads have different skin porosities and macro-void structures. The mixed matrix NF membrane of 1 wt% had the lowest irreversible fouling ratio (1.1%) and high antifouling potential with highest flux recovery after humic acid filtration with less change in the rejection. The absence of the used nanoparticales in treated water as well as non toxic properties indicates that the fabricated membranes are safe to be used for filtration. [ABSTRACT FROM AUTHOR]

ABSTRACT: The effect of zeolite 3A, 4A, and ZSM‐5 on the gas separation performance of polyurethane (PU)–zeolite mixed matrix membranes (MMMs) has been investigated in this study. Permeation of pure CO2, CH4, N2, and O2 gases through PU–zeolite MMMs with zeolite content of 6, 12, 18, and 24 wt% was studied. The prepared hybrid membranes were characterized using Fourier transform infrared spectroscopy and scanning electron microscope. Membrane characterization confirmed the homogeneous distribution of zeolite particles at low zeolite loadings in the prepared membranes. The obtained results confirmed a significant enhancement in the permeability of all gases and the CO2/N2, CO2/CH4, and O2/N2 selectivities by increasing the content of zeolite particles in PU–zeolite MMMs. The PU–zeolite 4A with 12 wt% zeolite loading showed the best performance in terms of gas permeability and selectivity for CO2/N2, CO2/CH4 and O2/N2 gas pairs. [ABSTRACT FROM AUTHOR]

Inorganic membrane science and technology is an attractive field of membrane separation technology, which has been dominated by polymer membranes. Recently, the inorganic membrane has been undergoing rapid development and innovation. Inorganic membranes have the advantage of resisting harsh chemical cleaning, high temperature and wear resistance, high chemical stability, long lifetime, and autoclavable. All of these outstanding properties made inorganic membranes good candidates to be used for water treatment and desalination applications. This paper is a state of the art review on the synthesis, development, and application of different inorganic membranes for water and wastewater treatment. The inorganic membranes reviewed in this paper include liquid membranes, dynamic membranes, various ceramic membranes, carbon based membranes, silica membranes, and zeolite membranes. A brief description of the different synthesis routes for the development of inorganic membranes for application in water industry is given and each synthesis rout is critically reviewed and compared. Thereafter, the recent studies on different application of inorganic membrane and their properties for water treatment and desalination in literature are critically summarized. It was reported that inorganic membranes despite their high synthesis cost, showed very promising results with high flux, full salt rejection, and very low or no fouling. [ABSTRACT FROM AUTHOR]

Mixed matrix membrane is composed of polymer matrix reinforced with organic or inorganic particles to improve its performance. This review presents comprehensive study on fabrication, properties, and application of polymeric composite-based mixed matrix membrane. Inorganic fillers (silica, alumina, and zeolite) are extensively used in mixed matrix membrane due to low cost, abundance, and simplistic surface treatment. Organic fillers (graphene and carbon nanotube) are also preferred due to low specific gravity, and high thermal, flame, and chemical resistance. Reinforcement of these nanofiller during membrane provides flux enhancement and low fouling. Various applications of mixed matrix membrane such as in tissue engineering, catalysis, and electrochemistry have also been discussed. [ABSTRACT FROM PUBLISHER]

Graphene oxide nanoplates (GONs) embedded mixed matrix polyvinylchloride based heterogeneous cation exchange membranes were prepared by solution casting. The effect of the concentration of GONs on the physico-chemical properties of the membrane was studied. Scanning electron microscopy (SEM) and scanning optical microscopy (SOM) images showed a uniform particle distribution and a uniform surface for the modified membranes. Moreover, the cross-sectional SEM images showed a specific direction for GO nanoplates, perpendicular to the membrane surface. XRD patterns showed that the average particle size of was enhanced by increasing the GONs dosage. The surface hydrophilicity of the membranes was improved, and the water content was lower by increasing the GON content. The IEC of the membranes was enhanced from 1.15 to 1.40 meq/g by an increase of the GON concentration up to 0.5 wt% in the casting solution, and decreased by a further increase of the content of GONs. The membrane potential, transport number, selectivity and conductivity were improved by utilizing GONs. The ion permeability and flux decreased initially by using GONs up to 0.5 wt%, followed by a sharp increasing trend at higher concentrations of GONs. [ABSTRACT FROM AUTHOR]

In this paper, the synergetic influence of various weight ratios of TiO 2 nanoparticles (NPs)/graphene oxide nanoplates (GONs) in the matrix of ion exchange membranes was examined in order to adapt their electrokinetic properties based on the combination of the high specific surface area of GONs and the antifouling ability of TiO 2 nanoparticles. The morphology, physico-chemical features and ionic transport behavior of prepared membranes was studied. Scanning optical microscopy (SOM) and scanning electron microscopy (SEM) images showed a uniform surface for the lab-made membranes relatively. It was found that surface hydrophilicity of the membrane was increased in the presence of GONs and TiO 2 NPs. All modified membranes showed a higher water uptake than unmodified membranes. Furthermore, a higher ion exchange capacity, fixed ionic concentration, ionic permeability and flux were observed for all modified membranes in comparison with unmodified membranes. The membrane potential, transport number and selectivity improved in NaCl solutions by using GONs and TiO 2 nanoparticles. Furthermore, the membrane ionic conductivity showed an increasing trend by utilizing TiO 2 -co-GONs NPs. As an overall conclusion, the modified membrane containing 3 wt% GONs and 1 wt% TiO 2 NPs with superior transport number and permselectivity (∼99%), highest current density and cation flux and the lowest areal electrical resistance (∼4–5 Ω cm 2 ) showed the best performance. [ABSTRACT FROM AUTHOR]