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Dialysis membranes are not hemocompatible with human blood, as the patients are suffering from the blood–membrane interactions' side effects. Zwitterionic structures have shown improved hemocompatibility; however, their complicated synthesis hinders their commercialization. The goal of the study is to achieve fast functionalization for carboxybetaine and sulfobetaine zwitterionic immobilization on PES membranes while comparing the stability and the targeted hemocompatibility. The chemical modification approach is based on an aminolysis reaction. Characterization, computational simulations, and clinical analysis were conducted to study the modified membranes. Atomic force microscopy (AFM) patterns showed a lower mean roughness for carboxybetaine-modified (6.3 nm) and sulfobetaine-modified (7.7 nm) membranes compared to the neat membrane (52.61 nm). The pore size of the membranes was reduced from values above 50 nm for the neat PES to values between 2 and 50 nm for zwitterionized membranes, using Brunauer–Emmett–Teller (BET) analysis. More hydrophilic surfaces led to a growth equilibrium water content (EWC) of nearly 6% for carboxybetaine and 10% for sulfobetaine-modified membranes. Differential scanning calorimetry (DSC) measurements were 12% and 16% stable water for carboxybetaine- and sulfobetaine-modified membranes, respectively. Sulfobetaine membranes showed better compatibility with blood with respect to C5a, IL-1a, and IL-6 biomarkers. Aminolysis-based zwitterionization was found to be suitable for the improvement of hemodialysis membranes. The approach introduced in this paper could be used to modify the current dialysis membranes with minimal change in the production facilities. [ABSTRACT FROM AUTHOR]

ESRD patients suffer from side effects of the dialysis process. Comprehension of different operational parameters' effect on the hemocompatibility profiles of the separative membranes, i.e. dialyzers, could result in designing more compatible materials. This study includes a computational approach to assess the effect of pH by assessing different uremic metabolites' behavior. The pH effect was assessed by comparing the water interaction ability of different uremic metabolites (which appear at different bloodstream pH levels) using molecular dynamics (MD) simulations. Based on the findings of the studies, a new class of zwitterionic materials is introduced. The proposed modification, containing guanidine (GNDM) was experimentally implemented on poly ether sulfone (PES) membranes. Aminolysis and sultone-ring opening reactions were used to immobilize the zwitterionic structure. Attuned total reflectance-Furrier transmission infrared spectroscopy (ATR-FTIR) was used to characterize the functional groups of the modified membrane. Gravimetry was used to measure the amount of modification layer added to the membrane as well as the equilibrium water content (EWC). Atomic force microscopy (AFM) was used to measure the roughness patterns of the neat and modified membranes. Zeta potential analyzer was used to check the trend of surface charge variations. Differential scanning calorimetry (DSC) was used to assess the stable water content of the membranes. A filtration test was performed to check the stability of the immobilized materials on the membranes. The newly modified PES membranes were nearly 50 % smoother and negatively charged. DSC reflects a 16 % higher content of stable water for the modified membranes. Computational assessments also reflected that the modified structure created more hydrogen bonds and could keep the water molecules more stable on the surface of the membrane. As the new membrane owned a higher capability to keep the water more stable on its surface, it could be a perfect candidate for a hemocompatible dialysis membrane. [Display omitted] • A uremic metabolite-attached zwitterionic dialysis membrane was fabricated. • The stability of the hydration layer on the modified membranes was measured. • Standard membrane characterizations were performed to confirm the structure. • The behavior of the water molecules on the modified membrane was assessed computationally. • The durability of the modification layer was assessed using filtration and ATR-FTIR-assisted functional group tracking. [ABSTRACT FROM AUTHOR]

Hemodialysis (HD) membrane materials-blood hemocompatibility is considered as the most important reason for intra- and post hemodialysis complications. The incompatibility could result in different cascade activations due to the interactions between vital human serum proteins (HSPs) and HD membranes. This study aims to assess the interaction energy between common hemodialysis polymer structures in the zwitterionized state and HSPs using molecular dynamics (MD) simulation to offer a framework for understanding the dominant interactions as a reference for HD material development. To perform zwitterionization, a feasible mussel-inspired methodology was used. Poly aryl ether sulfone (PAES) and cellulose triacetate (CTA) were chosen for the base membrane models and carboxybetaine methacrylate (CBMA), sulfobetaine methacrylate (SBMA), and phosphobetaine methacrylate (PBMA) were picked as common zwitterionic structures (ZWs) for surface modification. Human serum albumin (HSA), fibrinogen (FB), and transferrin (TRF) were selected as the models of HSPs. Polydopamine (PDA) was used for the binding structure. The binding energy of the membrane models and selected proteins, as well as the hydrophilicity of the membrane models, was assessed. Hydrophilicity assessment of the membrane models suggests that PBMA creates more tendency to water molecules when the modifying layer is located on both CTA- and PAES-based membrane models. The results suggest that the hemocompatibility of the membranes does not directly correlate with the hydrophilicity of the polymeric structures. While each protein creates a specific trend when interacting with membrane models with different base polymers and modifying layers, natural biomolecules such as PDA or carboxybetaine structures are suggested to eliminate FB's interactions. For biocompatibility enhancement, as well as hydrophilicity enhancement, sulfo- and phosphobetaine-containing coatings could be used. [ABSTRACT FROM AUTHOR]

End stage renal disease (ESRD) affects ≈10% of the world's population. Hemodialysis (HD) is a life‐sustaining extracorporeal blood purifying treatment for ESRD patients. Despite the advances in technology, the hemoincompatibility of the dialyzers leads to a high morbidity and mortality rate. Decreasing interactions between polymers and blood constituents will result in controlled binding of human serum proteins to the surface and consequently enhanced biocompatibility. This study aims to assess the interaction energy between common hemodialysis polymer structures and human serum proteins using molecular dynamics simulation to offer a framework for understanding the dominant interactions as a reference for material development. Molecular dynamics and molecular docking simulations are conducted for calculating polymerprotein binding energies. Common serum proteins are selected for protein models. Poly aryl ether sulfone (PAES) with and without polyvinyl pyrrolidone (PVP), polyvinylidene fluoride (PVDF), cellulose triacetate (CTA), polyacrylonitrile (PAN), and polymethyl methacrylate (PMMA) membrane structures are chosen as the different classes of dialyzers. The van der Waals interactions between polymers and proteins dominate the binding energies sequence. Molecular docking results of the affinity between protein receptors‐ligands are aligned with the MD binding interaction. [ABSTRACT FROM AUTHOR]

Despite advances in the field, hemoincompatibility remains a critical issue for hemodialysis (HD) as interactions between various human blood constituents and the polymeric structure of HD membranes results in complications such as activation of immune system cascades. Adding hydrophilic polymer structures to the membranes is one modification approach that can decrease the extent of protein adsorption. This study conducted molecular dynamics (MD) simulations to understand the interactions between three human serum proteins (fibrinogen [FB], human serum albumin, and transferrin) and common HD membranes in untreated and modified forms. Poly(aryl ether sulfone) (PAES) and cellulose triacetate were used as the common dialyzer polymers, and membrane modifications were performed with 2‐hydroxymethyl methacrylate (HEMA) and poly (2‐methoxyethyl acrylate) (PMEA), using polydopamine‐assisted co‐deposition. The MD simulations were used as the framework for binding energy simulations, and molecular docking simulations were also performed to conduct molecular‐level investigations between the two modifying polymers (HEMA and PMEA) and FB. Each of the three proteins acted differently with the membranes due to their unique nature and surface chemistry. The simulations show PMEA binds less intensively to FB with a higher number of hydrogen bonds, which reflects PMEA's superior performance compared to HEMA. The simulations suggest PAES membranes could be used in modified forms for blood‐contact applications as they reflect the lowest binding energy to blood proteins. [ABSTRACT FROM AUTHOR]

Proteins in dairy streams result in organic fouling and function loss for ceramic membrane's porous structure. Synchrotron‐based X‐ray microtomography (SR‐µCT) is a new method with a high signal to noise ratio and accordingly significant level of accuracy. The goal of this study was to perform an in situ assessment of ceramic membrane fouling in the dairy stream filtration process, using SR‐µCT. This study attempted to assess porosity variation and membrane fouling through different layers from the top, middle, and bottom layers of the ceramic microfiltration membrane before and after skimming milk filtration. Molecular dynamics simulation (MDS) was used for depth understanding of milk protein interactions with the ceramic membrane. Fouling was found to be more intense on the top of the ceramic membrane even though the top layer was slightly more porous, which indicates that top layers were more prone to fouling. A regression model was derived to correlate the porosity loss due to membrane fouling at different membrane thicknesses. The MDS results showed more affinity of the milk proteins to the ceramic membrane compared to water molecules. The MDS studies showed how the presence of the milk's protein macromolecules could change the hydrophilicity trend on the membrane's surface. [ABSTRACT FROM AUTHOR]

Abstract Drinking water scarcity is an ever-increasing global concern. This issue appears as a greater threat to the countries with no access to sea water resources or rivers, since their potential water resources are only limited to ground waters only. There are serious concerns with the treatment of ground water resources, including landfill leachates, agricultural contaminations (pesticides, herbicides, and fertilizers), and rural contaminations. Membrane separation has been proved to be the governing technology in water and wastewater treatment plants, as these methods are responsible for more than half of the market share of the world's desalination capacity. This study intends to offer a holistic view of the groundwater contamination with specific focus on Saskatchewan province in Canada, and the recent efforts in the groundwater treatment using thin film composite membrane technology. This study begins with an introduction of the general aspects of ground water and membrane separation, polluting agents, and their sources. It is followed by a discussion of Saskatchewan's groundwater status and various issues. Furthermore, the recent research that became available since 2010 is reviewed in details and the results are summarized with respect to purification efficiency. Different affecting parameters in a groundwater-thin film composite system are synthesized and an in-depth overview is presented. Graphical abstract Unlabelled Image [ABSTRACT FROM AUTHOR]

Abstract Renewable energy assisted water desalination technologies are currently becoming attractive as a solution for the water scarcity crisis. Global growth, sustainable development of technologies, and other critical areas are all significantly impacted by water access. Higher living standards and population growth along with industrial developments have resulted in an increased rate of water consumption. Furthermore, more countries are experiencing severe droughts while their drinkable water resources are being limited. Iran, as our case study is one of the countries suffering from such a problem as it has entered into water-bankruptcy period. This study analyzed the country's general water background and its renewable energy status, in addition to the potential in renewable energy assisted desalination (RED). Research reported suggests that Iran's potential in RED water production is more than 28 billion cubic meter in the case limited to only wind and solar potentials put into practice. Thus, Iran should be considered as a prototype in the solutions for water scarcity in cases of proper investment and planning. The critical case study offers an in-depth analysis which could be used as a strategic guide for different regions as it offers more secure solutions to future water concerns. Graphical abstract Iran's potential in Renewable energy assisted desalination capacity. Image 1042 Highlights • Renewable energy assisted water desalination is a solution to the water scarcity. • This study analyzed Iran's potential in renewable energy assisted desalination. • RED potential water production is more than 28 billion cubic meters by wind and solar. • The critical case study offers in-depth analyses as a strategic guide. [ABSTRACT FROM AUTHOR]

There are abundant renewable energy sources in Iran such as wind, solar, geothermal, biomass. However, Iran is fully dependent on fossil fuels for industrial, residential and transportation sectors. It results in the country to be in top 10 producers of greenhouse gases (GHGs) into the atmosphere. GHGs can be controlled by incorporating renewable sources to produce energy. Therefore, renewable energy resources are becoming more attractive to develop sustainable energy development in Iran. However, the transformation from traditional fossil fuel infrastructures to advanced renewable technologies needs many considerations, such as strategic and core planning. In this regard, this paper covers the current state of Iran's energy market focusing on both fossil fuels and renewable energy resources. A general review is offered over the renewable energy production status in Iran and the production potentials. Finally, in conclusion, a comparisons are made over the current state, plans and also potential opportunities of Iran over each sort of energy production. [ABSTRACT FROM AUTHOR]

Abstract: Antibacterial polysulfone ultrafiltration membranes were fabricated using different silver nanoparticles in the casting solution. X-ray diffraction (XRD), scanning electron microscopy (SEM), atomic force microscopy (AFM), contact angle and dead end filtration experiment were carried out to characterize the morphology and performance of the prepared membranes while inhibition zone and filtration of bacterial suspension were used to investigate the antibacterial behavior of the membranes. Sliver release was measured in order to investigate the kinetic of silver leaching from the membranes. Less crystalline structure was obtained for membrane with smaller silver nanoparticles as confirmed by the XRD patterns. In addition, SEM studies also showed that surface pores size was reduced by adding silver nanoparticle in the casting solution. Cross section of membranes were totally affected by the addition of silver nanoparticles so that tighter finger-like structure appeared by adding 70nm silver nanoparticles. As shown in SEM images, a dense cross section was formed by addition of 2wt.% silver nanoparticles with size of 30nm in the casting solution. Surface roughness parameters obtained from AFM images showed that the silver nanoparticles with size of 70nm caused rougher surface for membrane. However, the silver nanoparticles with the size of 30nm resulted in formation of membranes with smoother surfaces. Contact angle measurement also proved more hydrophilic surface for silver modified membranes. Inhibition zone and bacterial filtration showed higher antibacteriality for membranes with smaller silver nanoparticles. [Copyright &y& Elsevier]

Computational frameworks have been under specific attention within the last two decades. Molecular Dynamics (MD) simulations, identical to the other computational approaches, try to address the unknown question, lighten the dark areas of unanswered questions, to achieve probable explanations and solutions. Owing to their complex microporous structure on one side and the intricate biochemical nature of various materials used in the structure, separative membrane materials possess peculiar degrees of complications. More notably, as nanocomposite materials are often integrated into separative membranes, thin-film nanocomposites and porous separative nanocomposite materials could possess an additional level of complexity with regard to the nanoscale interactions brought to the structure. This critical review intends to cover the recent methods used to assess membranes and membrane materials. Incorporation of MD in membrane technology-related fields such as desalination, fuel cell-based energy production, blood purification through hemodialysis, etc., were briefly covered. Accordingly, this review could be used to understand the current extent of MD applications for separative membranes. The review could also be used as a guideline to use the proper MD implementation within the related fields. [Display omitted] • Overview of molecular dynamics simulation for membrane separation and porous materials. • MD-driven Initial Parameters. • Contribution of Computational Tools to Different Membrane Technology Subsections. • Instances of MD Applications for Characterization Membrane Materials. [ABSTRACT FROM AUTHOR]

• PAES hemodialysis membrane was selected for blood-membrane interaction study. • Blood- membrane interactions were investigated using spectroscopy analyses. • PAES morphological variation and blood attachments clots were investigated. • Binding energy between human serum proteins and PAES was studied using MDS. Patients with end-stage renal diseases (ESRD) require specific health cares as the accumulation of toxins due to the lack of kidney functionality would affect their lives. However, the mortality rate is still high due to cardiovascular diseases, socks, etc. A majority of patients with chronic kidney disease (CKD) require hemodialysis services. Blood purifying membranes, as the main component of hemodialysis setups, however, still suffer from lack of optimum biocompatibility, which results in morbidity and mortality of hemodialysis service receiving patients. The goal of the present case study is to have an in-depth understanding of the current blood-hemodialysis membrane interactions occurring during hemodialysis sessions using poly (aryl ether sulfone)-poly (vinyl pyrrolidone) (PAES-PVP) membrane. Attenuated total reflectance-Fourier transmission infrared (ATR-FTIR) spectroscopy, Raman spectroscopy, and solid-state nuclear magnetic resonance (SSNMR) spectroscopy were used to assess the initial chemical structure of the PAES-PVP membrane along with the variations after with the infections with human blood. Furthermore, scanning electron microscopy (SEM) and Transition electron microscopy (TEM) were used to visualize the structural variation of the membrane, blood aggregations, and blood clots on the membrane surface. Besides, Molecular dynamics (MD) simulation was used to assess the interaction of PAES-PVP with major human blood proteins, in terms of interaction energy, which is a novel contribution to the area. The macromolecules (human serum albumin (HSA), human serum transferrin (TRF), and human fibrinogen (HFG)) were chosen from the plasma protein component. These protein structures were chosen based on their different molecular size. Three advanced spectroscopy techniques and two advanced visualization techniques were used for the assessment of the membranes. Spectroscopy studies revealed amine related peak displacement and intensity shifts as indices for attachment of biological species to the polymeric membrane surfaces. Raman peaks around 370, 798, and 1299 cm−1, which experienced significant shifts that were related to carbon-nitrogen and sulfur-oxygen bonds due to protein adhesion. Visualization techniques illustrated blood protein fouling patterns and extracellular vesicles' presence in the pore structures into membranes. The findings highlight the importance of whole structure biocompatibility improvement, rather than only focusing on surface modifications of hemodialysis membranes. Molecular dynamics simulation assessment showed various interaction behaviors for different proteins suggesting molecular weight and active residues of the protein macromolecules play an important role in interacting with polymeric structure. FB had the highest interaction (4,274,749.07 kcal/mol) and binding (10,370.90 kcal/mol) energy with the PAES-PVP structure. TRF owned the lowest interaction energy with respect to its lower molecular weight and fewer active residue count. Image, graphical abstract Computational and experimental assessment of poly aryl ether sulfone structure for hemodialysis application. [ABSTRACT FROM AUTHOR]

Hemodialysis is a life-sustaining procedure for patients with end-stage renal disease (ESRD). The efficiency of hemodialysis is limited by the dialysis membrane biocompatibility and the poor clearance of middle-molecule uremic toxins. As a result, hemodialysis is associated with acute chronic side-effects that threaten patients' lives. During hemodialysis, interfacial interactions of blood-polymeric membranes result in several consequences. These interactions lead to the body's various system activations, including the coagulation of blood components, leukocytes (i.e., immune system activation) and complement activations, thrombogenesis, cytokine production, and appearance of radicals with free oxygen. Despite advances in research, the most vital issue in dialysis therapies is the biocompatibility and hemoincompatibility of the membranes. The process of enhancing membrane hemocompatibility is currently posing a global challenge. Reactions to incompatibility can cause severe injuries to the patients and result in morbidity and mortality. This critical review offers a focused analysis of the latest efforts to enhance the hemodialysis membrane's hemocompatibility as well as emphasize current research gaps. Recent innovations (since 2014) in hemodialysis membranes are analyzed in correlation to categories of modified polymer structure chemistry tuning, and surface modifications and their influences on membrane hemocompatibility. Particular attention is paid to: (1) chemical immobilization of functional groups (surface grafting); (2) layer-by-layer chemical attachment of species (LBL); (3) covalent attachment of super hydrophilic-hydrogel; (4) mixed matrix membranes (MMM); and (5) base polymer membrane modification (blending method). This critical review provides an overview of the effects the modification methods can have on biocompatibility and how they can pave the way for optimum enhancement of hemodialysis membrane biocompatibility. Unmodified membrane with blood clots and cascade reaction products (Image 2 representing cytokines, Image 3 representing leucocytes, Image 4 representing complement activation enzymes, Image 5 representing blood clots), modification techniques for polymeric hemodialysis membranes: chemical immobilization of functional groups (surface grafting), layer by layer chemical attachment of species (LBL), covalent attachment of super-hydrophilic hydrogel, mixed matrix membrane (MMM) and base polymer modification (blending). Image 1 • Body systems' response to hemodialysis membranes were reviewed. • Biocompatibility issues regarding complement activation and thrombogenesis were discussed. • Conventional hemodialysis modified membrane assessments were introduced. • Advances in hemodialysis modification researches targeting biocompatibility issues were reviewed. [ABSTRACT FROM AUTHOR]

Abstract: In this research, the surface of poly (vinylidene fluoride) (PVDF)/sulfonated polyethersulfone (SPES) blend membrane prepared via immersion precipitation was modified by depositing of TiO2 nano-particles followed by UV irradiation to activate their photocatalytic property. The membranes were characterized by FTIR, SEM, AFM, contact angle, dead end filtration (pure water flux and BSA solution flux), antifouling analysis and antibacterial activity. The FTIR spectrum confirmed the presence of OH functional groups on the PVDF/SPES membrane structure, which was the key factor for deposition, and self-assembly of TiO2 nanoparticles on the membrane surface. The SEM and AFM images indicated that the TiO2 nanoparticles were deposited on the PVDF/SPES membrane. The contact angle measurements showed that the hydrophilicity of PVDF/SPES membrane was strongly improved by TiO2 deposition and UV irradiation. The filtration results indicated that the initial flux of TiO2 deposited PVDF/SPES membranes was lower than the initial flux of neat PVDF/SPES membrane. However, the former membranes showed lower flux decline compared to the neat PVDF/SPES membrane. The BSA rejection of modified membranes was improved. The fouling analysis demonstrated that the TiO2 deposited PVDF/SPES membranes showed the fewer tendencies to fouling. The results of antibacterial study showed that the UV irradiated TiO2 deposited PVDF/SPES membranes possess high antibacterial property. [Copyright &y& Elsevier]

• Transesterification reactors for biodiesel production are comprehensively reviewed. • The effects of the main parameters on the transesterification process are scrutinized. • Pros and cons of each reactor technology for biodiesel production are outlined. • The sustainability aspects of biodiesel production are comprehensively discussed. • Policy and economic aspects of biodiesel have been extensively securitized. Diesel engines are preferred over spark ignition counterparts for heavy-duty applications and power generation plants because of their higher efficiency, durability, and productivity. Currently, the research interests have been propelled towards renewable and sustainable diesel fuels such as biodiesel in order to address the environmental and energy security challenges associated with these energy systems. However, the most challenging issue concerning large-scale production of biodiesel is its relatively high cost over fossil-based diesel owing to high feedstock and manufacturing costs. Therefore, cost-effective and eco-friendly biodiesel production technologies should be necessarily developed and continuously improved in order to make this biofuel more competitive vs. its petroleum counterpart. Accordingly, this paper comprehensively reviews biodiesel manufacturing techniques from natural oils and fats using conventional and advanced technologies with an in-depth state-of-the-art focus on the utmost important unit, i.e., transesterification reactor. The effects of the main influential parameters on the transesterification process are first discussed in detail in order to better understand the mechanisms behind each reactor technology. Different transesterification reactors; e.g. , tubular/plug-flow reactors, rotating reactors, simultaneous reaction-separation reactors, cavitational reactors, and microwave reactors are then scrutinized from the scientific and practical viewpoints. Merits and limitations of each reactor technology for biodiesel production are highlighted to guide future R&D on this topic. At the end of the paper, the sustainability aspects of biodiesel production are comprehensively discussed by emphasizing on the biorefinery concept utilizing waste-oriented oils. [ABSTRACT FROM AUTHOR]

Amine functionalized Multi-walled carbon nanotubes (F-MWCNTs)/polyethersulfone (PES) membranes were prepared using phase inversion induced by immersion precipitation. Crude MWCNTs were chemically treated using strong acids (H2SO4/HNO3) and 1,3-phenylenediamine (mPDA) to produce the functional amine groups (NH2) on their surfaces. F-MWCNTs with different concentration were blended in the casting solution containing PES, polyvinylpyrrolidone (PVP) and dimethylacetamide (DMAC). Pure water was used as non-solvent. The FTIR spectra indicated that the amine functional groups were produced on the surface of MWCNTs. The membranes prepared with different concentrations of F-MWCNTs were characterized using contact angle, field emission scanning electron microscopy (FESEM), scanning electron microscopy (SEM), atomic force microscopy (AFM) and permeation tests. The surface hydrophilicity of membranes was significantly improved by addition of F-MWCNTs in the casting solution. An increment in the porosity, pore size and surface roughness of the membranes was observed by increasing F-MWCNTs content up to 1 wt.%. Further addition of F-MWCNTs caused a reduction in porosity and roughness of formed membrane. The membranes prepared with 0.5 and 1 wt.% of F-MWCNTs showed higher performance than neat membrane. Addition of F-MWCNTs in the casting solution improved the BSA rejection and antifouling properties of PES membrane. [ABSTRACT FROM AUTHOR]

• State-of-the-art ultrasound technique for membrane fouling control and cleaning was reviewed. • Cavitation phenomenon as well as theory of ultrasonic-assisted effects were discussed. • Operational factors that influence the effectiveness of the ultrasound treatment were explained. • Effects of ultrasonic irradiation on integrity of the membranes were discussed. • The economic aspect of ultrasonically cleaning of membranes as a determinative parameter was investigated. Fouling is one of the most challenging problems impacting the performance of membrane-based separation technology. In recent years, ultrasound have been widely applied as an unconventional method to control membrane fouling, as well as to enhance membrane cleaning. The aim of the present work is to review the current literature and the recent developments related to the use of ultrasound as an innovative and alternative approach to improve the fouling behavior of membrane separation processes. The theory underlying ultrasonic-assisted phenomena is reviewed, together with operational factors that influence the effectiveness of the ultrasound treatment, such as frequency, power intensity, pressure, temperature, pH, and operation mode. Ultrasound irradiation effectively aids the cleaning of contaminated surfaces and enhances the permeate flux, owing to cavitation phenomena and powerful convective currents, associated with secondary phenomena, such as microstreamers, shock waves, and heating. However, the lifetime of the membranes should be carefully evaluated when applying ultrasonication as a technique of cleaning or controlling membrane fouling. Indeed, the integrity of membranes after sonication and the control of erosion produced by high ultrasonic intensities are key issues hindering the scale-up of this approach in the membrane industry. This reviews highlights the topics requiring more investigations, specifically to evaluate the economic aspects of ultrasonic assisted fouling control and cleaning in membrane processes. [ABSTRACT FROM AUTHOR]

Forward osmosis (FO) is an osmotically driven process widely studied for water desalination, wastewater treatment, and water reuse, as well as dilution and concentration of aqueous streams. However, its application is still hampered by the lack of ideal draw solutes, high-performance membranes, and fouling/biofouling. Biofouling is particularly challenging when FO is applied for seawater desalination and wastewater treatment. Over the last decade, many attempts have been made to exploit advances in materials science to obtain membranes with anti-biofouling properties to prevent or to reduce the detrimental effects of this phenomenon. In this review, we address the various approaches of membrane surface functionalization for biofouling control and mitigation. Recent developments in surface modification of thin-film composite and asymmetric membranes using surface coating, surface functionalization, and incorporation of tailored materials for biofouling control in FO are critically discussed. The future perspectives of anti-biofouling materials and FO membranes are reviewed to shed light on the future research directions for developing the true potential surface modification approach for the FO process. • Mechanism of biofouling in FO membranes and the current control strategies are presented. • Recent advances in the science of materials and their exploitation in engineering FO are discussed. • Methods for functionalization of FO membranes to mitigate the biofouling are reviewed. • Directions for future research in functionalized FO membrane development to biofouling control are proposed. [ABSTRACT FROM AUTHOR]