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This study investigated the development of poly(vinylidene fluoride) (PVDF) hybrid ultrafiltration membranes, where ZIF-8 nanocrystals are synthesized in situ within the membrane pores. These ZIF-8 embedded membranes are specifically designed for the treatment of emerging pollutants, such as ibuprofen. The optimized membrane, characterized by a higher concentration of ZIF-8 and greater surface coverage, exhibited significantly enhanced performance and improved properties, including increased hydrophobicity and mechanical strength. By increasing the zinc concentration from 0.2 to 0.3 M during the preparation of the ZIF-8 coated membrane, hydrophobicity was enhanced, as indicated by an increase in the contact angle from 60.3° to 87.2°, along with improved porosity from 41.3% to 60.5%. Further performance enhancements were achieved by encapsulating enzymes, specifically laccase and peroxidase, within the ZIF-8 coated membrane. A comparison of ibuprofen removal by these enzymes showed that peroxidase was slightly more effective, reaching a maximum removal efficiency of approximately 45% within 2 h. The biocatalytic membranes demonstrated a high stability and reusability, underscoring their potential for efficient ibuprofen removal. These findings highlight the efficacy of ZIF-8-coated PVDF membranes as advanced tools for water purification, offering significant improvements in both purification efficiency and membrane stability.

This work explores the bio-activation of zeolitic imidazolate framework (ZIF-L) by laccase encapsulation for enhanced performance of emerging pollutant removal from wastewater. ZIF-L exhibits high surface area, porosity, and selective adsorption characteristics, which contribute to its effective adsorption of ibuprofen. Under the same conditions, the ibuprofen removal increased from 50% using bare ZIF-L to 83% using bio-activated ZIF-L. The Kinetics and thermodynamics of ibuprofen adsorption on ZIF-L were studied and mathematically modeled. The effect of laccase encapsulation inside the ZIF-L crystals was thoroughly investigated using a diffusion-reaction model, which was solved numerically using a finite difference explicit scheme. The results showed deep ibuprofen penetration within the ZIF-L crystal containing encapsulated laccase. The bio-activated ZIF-L was used in a fixed-bed column to study the continuous removal of ibuprofen. The dynamic behavior of the continuous fixed-bed system was mathematically modeled to predict the concentration profiles and breakthrough curves at various initial ibuprofen concentrations. This study presents a novel approach demonstrating the positive effect of laccase catalytic activity in enhancing the performance of ZIF-L as an adsorbent for ibuprofen removal. The approach offers an effective, economical, and environmentally friendly method to remove emerging pollutants from wastewater.

The presence in seawater of low-molecular-weight polyethylene (PE) and polydimethylsiloxane (PDMS), synthetic polymers with high chemical resistance, has been demonstrated in this study for the first time by developing a novel methodology for their recovery and quantification from surface seawater. These synthetic polymer debris (SPD) with very low molecular weights and sizes in the nano- and micro-metre range have escaped conventional analytical methods. SPD have been easily recovered from water samples (2 L) through filtration with a nitrocellulose membrane filter with a pore size of 0.45 μm. Dissolving the filter in acetone allowed the isolation of the particulates by centrifugation followed by drying. The isolated SPD were analysed by 1H nuclear magnetic resonance spectroscopy (1H NMR), identifying PE and PDMS. These polymers are thus persisting on seawater because of their low density and the ponderal concentrations were quantified in mg/m3. This method was used in an actual case study in which 120 surface seawater samples were collected during two sampling campaigns in the Mediterranean Sea (from the Gulf of Salerno to the Gulf of Policastro in South Italy). The developed analytical protocol allowed achieving unprecedented simplicity, rapidity and sensitivity. The 1H and 13C NMR structural analysis of the PE debris indicates the presence of oxidised polymer chains with very low molecular weights. Additionally, the origin of those low molecular weight polymers was investigated by analysing influents and effluents from a wastewater treatment plant (WWTP) in Salerno as a hot spot for the release of SPD: the analysis indicates the presence of low molecular weight polymers compatible with wax-PE, widely used for coating applications, food industry, cosmetics and detergents. Moreover, the origin of PDMS debris found in surface seawater can be ascribed to silicone-based antifoamers and emulsifiers.

Abstract The need for antifouling membranes is substantial due to fouling’s negative impact on the effectiveness and durability of ultrafiltration membranes. In recent times, Metal-Organic Frameworks (MOFs) have emerged as effective additives for crafting ultrafiltration (UF) membranes. However, to harness their benefits and mitigate their drawbacks, a well-considered approach is imperative. In this work, polyethersulfone (PES) UF membranes were tailored with polydopamine (PDA)-modified cerium (Ce)-MOF (PDA@Ce-MOF) to achieve satisfactory antifouling properties and to remove biological macromolecules such as bovine serum albumin (BSA) and humic acid (HA) from wastewater. The non-solvent induced phase separation (NIPS) method was used to simultaneously fabricate the membrane and modify it with different PDA@Ce-MOF concentrations ranging from 0.05 to 0.50 wt.%. Results showed significant improvements on the membrane’s morphology, hydrophilicity, porosity and pore size at 0.10 wt.% loading of PDA@Ce-MOF. The synergistic effect of the PDA and Ce-MOF on the membrane improved the pure water flux (337 L m−2 h−1) and filtration performance in the filtration of Bovine serum albumin (BSA) and humic acid (HA) reporting 145 L m−2 h−1 and 98% rejection, and 164 L m−2 h−1 and 88% rejection; respectively. Further, water-attracting functional moieties of PDA@Ce-MOF hindered the deposition of BSA protein on the membrane surface, resulting in an excellent flux recovery ratio (FRR) of ~87%, alongside mitigated irreversible fouling.

Abstract The aqueous system is being polluted by the untreated direct discharge of industrial oily wastewater into the ecosystem. Due to its low cost, energy economy, and sustainability, the advanced membrane filtration method is regarded as one of the best methods for treating oily wastewater. Its exceptional atomic thickness and superior amphiphilic properties of graphene oxide (GO) nanosheet make it one of the finest 2D constituents for creating membranes with high permeability. Nevertheless, the interlayer d-spacing of multi-stacked GO membranes is crucial since it is responsible for the permeability/selectivity trade-off. To efficiently separate oil-in-water emulsion using an in-situ polymerization technique, we developed an aquaporin-like 3D hierarchical multi-functionalized nanoporous graphene (NPG) membrane with tripartite nanochannels. The extraordinary, prepared membrane displayed both ultra-water-permeability of 2490 L m−2 h−1.bar along with superior selectivity. Consequently, the permeance of the aquaporin-like 3D hierarchical multi-functionalized NPG membrane achieves a higher flux than the GO membrane, while the oil rejection reaches ~97%.

Control and prevention of environmental pollution have emerged as paramount global concerns. Anthropogenic activities, such as industrial discharges, agricultural runoff, and improper waste disposal, introduce a wide range of contaminants into various ecosystems. These pollutants encompass organic and inorganic compounds, particulates, microorganisms, and disinfection by-products, posing severe threats to human health, ecosystems, and the environment. Effective monitoring methods are indispensable for assessing environmental quality, identifying pollution sources, and implementing remedial measures. This paper suggests that the development and utilization of highly advanced analytical tools are both essential for the analysis of contaminants in water samples, presenting a foundational hypothesis for the review. This paper comprehensively reviews the development and utilization of highly advanced analytical tools which is mandatory for the analysis of contaminants in water samples. Depending on the specific pollutants being studied, the choice of analytical methods widely varies. It also reveals insights into the diverse applications and effectiveness of these methods in assessing water quality and contaminant levels. By emphasizing the critical role of the reviewed monitoring methods, this review seeks to deepen the understanding of pollution challenges and inspire innovative monitoring solutions that contribute to a cleaner and more sustainable global environment. • Urgent global concerns: control and prevention of pollution from diverse sources. • Varied contaminants, diverse methods: comprehensive review of analytical tools. • Inspiring a sustainable future: innovative monitoring for a cleaner environment.

The freshwater shortage continues to be one of the greatest challenges affecting our planet. Although traditional membrane distillation (MD) can produce clean water regardless of climatic conditions, the process wastes a lot of energy. The technique of solar-powered membrane distillation (SPMD) has received a lot of interest in the past decade, thanks to the development of photothermal materials. SPMD is a promising replacement for the traditional MD based on fossil fuels, as it can prevent the harmful effects of emissions on the environment. Integrating green solar energy with MD can reduce the cost of the water purification process and secure freshwater production in remote areas. At this point, it is important to consider the most current progress of the SPMD system and highlight the challenges and prospects of this technology. Based on this, the background, recent advances, and principles of MD and SPMD, their configurations and mechanisms, fabrication methods, advantages, and current limitations are discussed. Detailed comparisons between SPMD and traditional MD, assessments of various standards for incorporating photothermal materials with desirable properties, discussions of desalination and other applications of SPMD and MD, and energy consumption rates are also covered. The final section addresses the potential of SPMD to outperform traditional desalination technology while improving water production without requiring a significant amount of electrical or high-grade thermal energy.

Oily wastewater presents a significant challenge that requires attention from the scientific community to not only treat it but also transform it into a valuable resource. Membrane-based separation techniques offer several advantages for treating oily wastewater, particularly in terms of ease of operation and lower energy requirements. The present research was aimed to develop polymeric-inorganic composite mixed matrix membranes (MMMs) for the treatment of surfactant stabilized oil-in-water (O/W) emulsions. These composite MMMs were fabricated using a non-solvent induced phase separation (NIPS) method, with polyvinyl alcohol (PVA)/glutaraldehyde (GA) serving as the matrix polymer and silicon carbide (SiC) nanoparticles incorporated into the matrix on a Nylon support. The concentrations of PVA (4, 10, and 12 wt%) and SiC nanoparticles (0, 0.1, 0.5, 1, 5, and 10 wt% relative to PVA) were varied for fabricating MMMs. In addition, other factors such as crosslinking times (10, 30, 60, and 240 min), and method of phase inversion (dry and wet) were also studied to yield the best-performing MMMs for O/W separation. The SiC content in the MMMs was found to have a significant impact on the physical characteristics of the membranes, such as surface morphology and porosity, which ultimately influenced the membrane performance. Hence, out of the six membranes tested for O/W separation, the M0.5 membrane containing 0.5 wt% SiC demonstrated high rejection (85 %) of total organic carbon (TOC) and a flux of 569.3 LMH when utilizing 100 ppm diesel O/W emulsion as the feed at 4 bar. This study underscores the potential of SiC MMMs for water treatment applications, while also emphasizing the need for further research to optimize their performance and resistance to fouling.

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has been detected in wastewater. Wastewater-based epidemiology (WBE) is a practical and cost-effective tool for the assessment and controlling of pandemics and probably for examining SARS-CoV-2 presence. Implementation of WBE during the outbreaks is not without limitations. Temperature, suspended solids, pH, and disinfectants affect the stability of viruses in wastewater. Due to these limitations, instruments and techniques have been utilized to detect SARS-CoV-2. SARS-CoV-2 has been detected in sewage using various concentration methods and computer-aided analyzes. RT-qPCR, ddRT-PCR, multiplex PCR, RT-LAMP, and electrochemical immunosensors have been employed to detect low levels of viral contamination. Inactivation of SARS-CoV-2 is a crucial preventive measure against coronavirus disease 2019 (COVID-19). To better assess the role of wastewater as a transmission route, detection, and quantification methods need to be refined. In this paper, the latest improvements in quantification, detection, and inactivation of SARS-CoV-2 in wastewater are explained. Finally, limitations and future research recommendations are thoroughly described.

The aim of this study is to develop an environmentally friendly and effective method for the extraction of nutritious date sugar using natural deep eutectic solvents (NADES) and ultrasound-assisted extraction (USAE). The careful design of a suitable NADES-USAE system was systematically supported by COSMO-RS screening, response surface method (RSM) and artificial neural network (ANN). Initially, 26 natural hydrogen bond donors (HBDs) were carefully screened for sugar affinity using COSMO-RS. The best performing HBDs were then used for the synthesis of 5 NADES using choline chloride (ChCl) as HBA. Among the synthesized NADES, the mixture of ChCl, citric acid (CA) and water (1:1:1 with 20 wt% water) resulted in the highest sugar yield of 78.30 ± 3.91 g/100 g, which is superior to conventional solvents such as water (29.92 ± 1.50 g/100 g). Further enhancements using RSM and ANN led to an even higher sugar recovery of 87.81 ± 2.61 g/100 g, at conditions of 30 °C, 45 min, and a solvent to DFP ratio of 40 mL/g. The method NADES-USAE was then compared with conventional hot water extraction (CHWE) (61.36 ± 3.06) and showed 43.1% higher sugar yield. The developed process not only improves the recovery of the nutritious date sugar but also preserves the heat-sensitive bioactive compounds in dates, making it an attractive alternative to CHWE for industrial utilization. Overall, this study shows a promising approach for the extraction of nutritive sugars from dates using environmentally friendly solvents and advanced technology. It also highlights the potential of this approach for valorizing underutilized fruits and preserving their bioactive compounds.

Abstract In this study, the synthesis, and chemical-physical characterization of self-assembled positively charged multi-walled carbon nanotubes/graphene oxide (f-MWCNTs)/(GO)-nanohybrids into adsorptive PLA-based membranes were investigated. The application of the innovative PLA/f-MWCNTs/GO membrane was investigated for the removal of nutrients such as nitrogen (N) and phosphorus (P) from both synthetic and real wastewater by performing various characterization and performance tests. The positively charged nanohybrid was prepared by electrostatic self-assembly of positively charged f-MWCNTs and negatively charged GO. The amount of nanohybrid loading in the nanocomposite membranes varied from 0 to 6 wt%, and its effects on nutrient removal and water flux were investigated. It is demonstrated that with the addition of only 1.5 wt% f-MWCNT/GO nanohybrid into the PLA matrix, the water flux increased by 74% when compared to the unmodified membrane. Also, up to 90.1 ± 3.4% and 71.3 ± 3.1% removal rates of ammonium-nitrogen (NH4 +-N) and phosphate (PO4 3−-P) ions were achieved using raw wastewater, respectively. The obtained results confirm the practical usability of the proposed innovative material for membrane fabrication in real wastewater treatment applications and can open doors to efficient and sustainable methods for nutrient removal.

Abstract Heavy metals (HMs) are highly toxic water pollutants abundant in industrial wastewater. Herein, a bis[3-(trimethoxysilyl)propyl]amine (BTMSPA) cross-linked multiwalled carbon nanotube (MWCNT) nanomaterial (CQACNT) was synthesized by silanization of MWCNT-OH followed by grafting of positively charged quaternary ammonium groups (glycidyl trimethyl ammonium chloride (GTMAC)) by an epoxide ring-opening reaction. The composite membranes were prepared by the incorporation of CQACNT into the poly(ether sulfone) (PES) polymer matrix. The CQACNT-6 composite membrane exhibited a 3.5-fold increase in pure water permeability (PWP; 312.8 L m−2 h−1 bar−1) as compared to the pristine PES (CQACNT-0) membrane (89.6 L m−2 h−1 bar−1). Moreover, the CQACNT-6 composite membrane showed high HM removal rates (Pb: 89.53%; Ni: 90.42%; Cu: 91.43%; Zn: 91.86%) as compared to the CQACNT-0 membrane (Pb: 39.73%; Ni: 40.32%; Cu: 42.52%; and Zn: 43.91%). After 9 treatment cycles, the CQACNT-6 membrane retained up to 87%, and 94% of its initial PWP and initial Cu2+ rejection, respectively, compared to only 58%, and 54%, respectively for pristine CQACNT-0. The positively charged quaternary ammonium groups enhanced the surface features of PES and MWCNTS, resulting in competitive HM removal rates due to the electrostatic repulsion between the HM and the porous membranes, as well as high PWP.

Abstract An advanced concept of aerobic membrane bioreactors (MBRs) for highly efficient wastewater treatment has been disclosed by introduction of an electro and encapsulated self-forming dynamic biomembrane (e-ESFDM). The biological filtering membrane is intercalated between two woven polyester fabrics as supports that assist the formation and protect the biomembrane. The innovative architecture of the e-ESFDM in combination with electrocoagulation processes resulted in efficient and cost-effective wastewater treatment and control of the membrane fouling. The performance of the e-ESFDMBR was compared to a yet highly efficient ESFDMBR, where the electric field was not present. The ESFDM-based reactors both showed comparable results in the removal of organic matter, in terms of COD and DOC. On the other hand, e-ESFDMBR exceeded the performance of the ESFDMBR in the reduction of nitrogen- and phosphorous-containing pollutants, responsible for eutrophication processes in the environment, and recalcitrant molecules, such as humic-like substances. In addition, an extremely low fouling rate was observed for the e-ESFDM bioreactor. Insights on the biological processes involved in the developed MBR were provided by investigations on the microbiological diversity found in reactor mixed liquor, ESFDM layer and treated wastewater.

The cultivation of microalgae for carbon capture and utilization (CCU) emerged as sustainable and effective platform to reduce GHGS and produce valuable biomass. In the study, systematic comparison of two identical algal photo-bioreactors (PBRw and PBRp), with white and purple led lights respectively, has been implemented. Carbon removals up to 98% has been obtained, with PBRp supporting enhanced cultivation conditions, higher CO2 removals and increased biomass production (up to 855 mg d−1 of dry algal biomass). The results demonstrate the potential of the proposed solutions as sustainable strategy to increase the applicability of algal photo-bioreactors for carbon capture and utilization.

Abstract Recent advances in wastewater treatment processes have resulted in high removal efficiencies for various hazardous pollutants. Nevertheless, some technologies are more suitable for targeting specific contaminants than others. We comprehensively reviewed the recent advances in removing hazardous pollutants from industrial wastewater through membrane technologies, adsorption, Fenton-based processes, advanced oxidation processes (AOP), and hybrid systems such as electrically-enhanced membrane bioreactors (eMBRs), and integrated eMBR-adsorption system. Each technology’s key features are compared, and recent modifications to the conventional treatment approaches and limitations of advanced treatment systems are highlighted. The removal of emerging contaminants such as pharmaceuticals from wastewater is also discussed.

Wastewater-based epidemiology (WBE) is a powerful tool that has the potential to reveal the extent of an ongoing disease outbreak or to predict an emerging one. Recent studies have shown that SARS-CoV-2 concentration in wastewater may be correlated with the number of COVID-19 cases in the corresponding population. Most of the recent studies and applications of wastewater-based surveillance of SARS-CoV-2 applied the “gold standard” real-time quantitative reverse transcription-polymerase chain reaction (RT-qPCR) detection method. However, this method also has its limitations. The paper aimed to present recent improvements and applications of the PCR-based methods for SARS-CoV-2 monitoring in wastewater. Furthermore, it aimed to review alternative methods utilized and/or proposed for the detection of the virus in wastewater matrices. From the review, it was found that several studies have investigated the use of reverse-transcription digital polymerase reaction (RT-dPCR), which was generally shown to have a lower limit of detection (LOD) over the RT-qPCR. Aside from this, non-PCR-based and non-RNA based methods have also been explored for the detection of SARS-CoV-2 in wastewater, with detailed attention given to the detection of SARS-CoV-2 proteins. The potential methods for protein detection include mass spectrometry, the use of immunosensors, and nanotechnological applications. In addition, the review of recent studies also revealed two types of emerging methods related to the detection of SARS-CoV-2 in wastewater: i) capsid-integrity assays to infer about the infectivity of SARS-CoV-2 present in wastewater, and ii) alternative methods for detection of SARS-CoV-2 variants of concern (VOCs) in wastewater. The recent studies on proposed methods of SARS-CoV-2 detection in wastewater have considered improving this approach in one or more of the following aspects: rapidity, simplicity, cost, sensitivity, and specificity. However, further studies are needed in order to realize the full application of these methods for WBE in the field.

Alternative sweeteners to white sugar with a lower calorie content and glycemic index obtained through date palm fruits is of great interest to the food industry. In this study, ultrasound-assisted extraction of nutritive sugar from date fruit powder was investigated through Box-Behnken design. A maximum total sugar content (TSC) of 812 mg glucose eq./g of DFP was obtained with a sugar extraction yield (SEY) of 81.40 ± 0.27 % under the following optimal extraction conditions: extraction temperature of 60 °C, extraction time of 30 min, and L/S ratio of 7.6 mL/g. Various modern techniques were used to characterize the obtained extracts and associated residues. The results showed that the extract contained fructose, glucose, and sucrose and had good thermal stability. Furthermore, SEM and TSC analysis revealed that ultrasonic treatment of the biomass improved mass transfer diffusion due to acoustic or ultrasonic cavitation, resulting in a higher sugar yield.

Thin-film nanocomposite (TFN) membranes are the third-generation membranes being explored for nanofiltration applications. Incorporating nanofillers in the dense selective polyamide (PA) layer improves the permeability–selectivity trade-off. The mesoporous cellular foam composite Zn-PDA-MCF-5 was used as a hydrophilic filler in this study to prepare TFN membranes. Incorporating the nanomaterial onto the TFN-2 membrane resulted in a decrease in the water contact angle and suppression of the membrane surface roughness. The pure water permeability of 6.40 LMH bar−1 at the optimal loading ratio of 0.25 wt.% obtained was higher than the TFN-0 (4.20 LMH bar−1). The optimal TFN-2 demonstrated a high rejection of small-sized organics (>95% rejection for 2,4-dichlorophenol over five cycles) and salts—Na2SO4 (≈95%) > MgCl2 (≈88%) > NaCl (86%) through size sieving and Donnan exclusion mechanisms. Furthermore, the flux recovery ratio for TFN-2 increased from 78.9 to 94.2% when challenged with a model protein foulant (bovine serum albumin), indicating improved anti-fouling abilities. Overall, these findings provided a concrete step forward in fabricating TFN membranes that are highly suitable for wastewater treatment and desalination applications.

The discharge of large volumes of oily wastewaters without sufficient treatment poses a huge risk on the environment. The main objective of this study was to investigate the capability of electro-coagulation/flotation (ECF) process for the removal of oil from industrial oily wastewater via different electrodes' configuration. These included anode-cathode-anode-cathode (ACAC), anode-cathode-cathode-anode (ACCA), and cathode-anode-anode-cathode (CAAC) electrode configurations. The impact of other operational conditions such as treatment time (30, 60, and 90 min), current density (50, 100 and 200 A/m2), and initial pH (4, 7, 10) was also investigated. Results showed that the up to 30.3% increase in oil removal can be achieved by optimizing the treatment time in the ACCA configuration. Similarly, it was found that operating at higher CD higher than 100 A/m2 resulted in a minor increase in oil removal in the same configuration. Optimal oil removal efficiency of 82% was achieved when the ECF system operated at a current density 100 A/m2, a treatment time of 90 min, an initial wastewater pH of 7, and using ACAC electrodes' configuration. An operational electrical energy consumption of 3.4 kWh/m3 and a treatment cost of USD 0.26/m3 were also reported for this configuration. It was concluded that oil removal using ECF process are very sensitive to changes in the electrode configuration, and an optimum configuration can be chosen by considering the time and cost of treatment.

In the light of the spread of treated wastewater use for irrigation, trace heavy metals pose a great risk to humans and aquatic life. An integrated electrochemical-adsorption (i.e. EC-AD) hybrid system was investigated for the removal of iron (Fe), zinc (Zn), and copper (Cu) traces from synthetic wastewater mimicking industrial wastewater. Slag, a by-product produced in steel industries, was utilized as the adsorbent. The performance of the EC-AD hybrid system was evaluated at mass to wastewater volume ratio (i.e. M/V) ranging from 0.01 to 0.07 g/mL, current density (CD) ranging between 5 and 15 A/m2 and treatment time ranging between 60 and 120 minutes. Furthermore, process kinetics (pseudo-first-order, pseudo-second-order, Elovich, adsorption kinetic models, and Weber-Morris intraparticle diffusion), and adsorption isotherms (Langmuir and Freundlich) were investigated to provide adsorption mechanisms that reflect the interaction between EC and AD processes in the hybrid system. The results indicated that Freundlich isotherm was able to fit the linearized data points compared to Langmuir with Fe and Zn. In addition, kinetic models suggested chemisorption as the predominant removal mechanism of Fe, Zn, and Cu using slag for the EC-AD system. Results showed that the use of EC-AD significantly enhanced the removal efficiency of heavy metal traces from wastewater, reaching 99%.

Using an environmentally friendly approach for eliminating methylene blue from an aqueous solution, the authors developed a unique electrospun nanofiber membrane made of a combination of polyethersulfone and hydroxypropyl cellulose (PES/HPC). SEM results confirmed the formation of a uniformly sized nanofiber membrane with an ultrathin diameter of 168.5 nm (for PES/HPC) and 261.5 nm (for pristine PES), which can be correlated by observing the absorption peaks in FTIR spectra and their amorphous/crystalline phases in the XRD pattern. Additionally, TGA analysis indicated that the addition of HPC plays a role in modulating their thermal stability. Moreover, the blended nanofiber membrane exhibited better mechanical strength and good hydrophilicity (measured by the contact angle). The highest adsorption capacity was achieved at a neutral pH under room temperature (259.74 mg/g), and the pseudo-second-order model was found to be accurate. In accordance with the Langmuir fitted model and MB adsorption data, it was revealed that the adsorption process occurred in a monolayer form on the membrane surface. The adsorption capacity of the MB was affected by the presence of various concentrations of NaCl (0.1–0.5 M). The satisfactory reusability of the PES/HPC nanofiber membrane was revealed for up to five cycles. According to the mechanism given for the adsorption process, the electrostatic attraction was shown to be the most dominant in increasing the adsorption capacity. Based on these findings, it can be concluded that this unique membrane may be used for wastewater treatment operations with high efficiency and performance.

Abstract Several studies have been carried out to understand bulking phenomena and the importance of environmental factors on sludge settling characteristics. The main objective of this study was to carry out functional characterization of microbial community structure of wastewater electro-bioreactor sludge as it undergoes serial passaging in the presence or absence of a current density over 15 days. Illumina MiSeq sequencing and QIIME were used to assess sludge microbial community shifts over time. (α) and (β) diversity analysis were conducted to assess the microbial diversity in electro-bioreactors. A phylogeny-based weighted UniFrac distance analysis was used to compare between bacterial communities while BIO-ENV trend and Spearman’s rank correlation analysis were performed to investigate how reactor operational parameters correlated with bacterial community diversity. Results showed that the removal efficiency of soluble chemical oxygen demand (sCOD) ranged from 91–97%, while phosphorous (PO4 3−-P) removal was approximately 99%. Phylogenetic analysis revealed stark differences in the development of sludge microbial communities in the control and treatment reactor. There was no mention of any studies aimed at characterizing functional microbial communities under electric field and the results communicated here are the first, to our knowledge, that address this gap in the literature.