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[Display omitted] • Photothermal BLC can be directely carbonized from bamboo leaves. • The BLC/MF achieves an evaporation rate up to 2.29 kg m-2h−1 under one-sun irradaition. • The BLC/MF exhibits the excellent stability for long-term solar steam generation. • Salt tolerant desalination and wastewater purification over BLC/MF are demonstrated. High-performance salt-resistant solar evaporators breaking the theoretical limit of solar steam generation are highly desired for solar water evaporation technology. However, low-cost, scalable and continuous solar steam generation remains a big challenge. Herein, a robust biomass-based salt-resistant three-dimensional (3D) evaporator is designed and developed, which is composed of bamboo leaf-derived carbon (BLC) and heat-insulating macroporous melamine foam (MF), showing the integrated merits for the boosted solar evaporation performances. The designed BLC/MF evaporator presents excellent photothermal conversion ability with an evaporation rate as high as 2.29 kg m-2h−1 and acceptable evaporation efficiency of 93.95 % under one-sun irradiation. The superior performance endows BLC/MF evaporator with flexible and versatile behaviors to purify various water sources to produce clean water meeting the standard level of World Health Organization (WHO) for drinkable water. Significantly, the BLC/MF evaporator maintains a similar evaporation rate in saline solutions and can work stably at high salinities without salt deposition. This present discloses that the BLC/MF evaporator can be served as a feasible and robust alternative for solar water evaporation in various water environment for clean water production. [ABSTRACT FROM AUTHOR]

• A 3D photothermal evaporator is fabricated by simply twisting a 2D PPy-coated sponge. • Twisted structure dilutes light density uniformly, enabling reduction of heat loss and recovery of environment energy. • Such an evaporator performs an ultra-high evaporation rate of ∼4.0 kg/m2h without salt scaling. Solar-powered evaporation emerges as a sustainable way to alleviate water stress by harvesting freshwater from diverse sources. Optimizing heat management by evaporator structures is becoming a mainstream strategy to promote solar-powered evaporation performance. In this work, we develop a novel evaporator design by simply twisting a two-dimensional polypyrrole-decorated sponge with excellent light-to-heat conversion capacity to reduce heat loss and recover environmental energy. The enlarged evaporation surface and reduced bulk water within the evaporator promote heat utilization in evaporation. The twisted structure dilutes the light density on the evaporator surface to reduce surface temperature, decreasing the driving force of heat transfer and promoting the contribution of environmental energy during evaporation. By integrating solar evaporation and environment evaporation, such an evaporator achieves an ultra-high evaporation rate of ∼4.0 kg·m−2·h−1 and an apparent evaporation efficiency exceeding 100% for 3.5 wt% saline solution. Smaller twisting angle lead to a higher calculated evaporation rate due to the reduced light density. Moreover, an evaporator array performs a high water production rate of 17.3 kg·m−2·day−1 in the outdoor experiment. [ABSTRACT FROM AUTHOR]

[Display omitted] • The concentration of Cl− has a significant impact on the conversion of oxidative species. • The CoS@FeS catalyst can improve RhB mineralization and inhibition of the AOX formation. • The in-situ generation of H 2 O 2 consumes HClO and thus inhibits the formation of AOX. • The H 2 O 2 concentration related closely with the catalyst and O 2 dosages. The presence of chloride ions (Cl−) in dye wastewater can hinder the peroxymonosulfate (PMS) oxidation and lead to the abundant production of toxic adsorbable organic halogens (AOX). In this study, we investigate the detailed influence of Cl− on Rhodamine B (RhB) removal and its mechanism, and propose a potential pathway for 1O 2 -dominated systems to inhibit AOX formation. The concentration of Cl− has a dual effect on the degradation of RhB, with low concentrations inhibiting and high concentrations promoting. Further studies have revealed that Cl− significantly impact the generation and transformation of reactive oxygen species (ROSs). EPR capturing, quenching tests, and molecular probe experiments indicate that as the Cl− concentration increases, the concentration of SO 4 −, OH and their contribution to the degradation of RhB gradually decrease, 1O 2 slightly increase and then decrease, while HClO and chlorine radicals increase linearly. Additionally, the catalyst plays a crucial role in inhibiting AOX formation and improving the mineralization of RhB. On the one hand, introducing catalysts can alter the proportion of ROSs production. On the other hand, the in-situ generation of H 2 O 2 on the catalyst surface, through O 2 adsorption at sulfur vacancies sites, consumes the produced HClO, thereby inhibiting the formation of AOX. This study proposed a new insight into the mechanism for effective reduction of AOX content for 1O 2 dominated non-radical PMS activation under saline water. [ABSTRACT FROM AUTHOR]

Graphical abstract The best electrochemical reactor design decreased TCA to values below 1.5 ng/L in 85% of the cork discs. Highlights • Cork discs contaminated with TCA were subjected to electrochemical treatment. • Six reactor designs and four experimental variables were tested. • A low current density of 0.16 mA/cm2 was applied for 8 h in all experiments. • The EC technology removed TCA from the contaminated cork discs. • The best EC system decreased TCA to values below 1.5 ng/L in 85% of the cork discs. Abstract The electrochemical (EC) process for the removal of 2,4,6-trichloroanisole (TCA) from cork discs was investigated for the first time. For process development, six different EC reactors (based on a 3-compartment set-up) and four process variables were tested. Independently of the reactor design used, the application of a low level direct current for 8 h (10 mA, 0.16 mA/cm2) had a positive effect on TCA removal. The best option is to place the cork discs in a middle compartment separated from the cathode compartment by the use of a passive membrane, and from the anode compartment by a cation exchange membrane. In this reactor design, the TCA levels in 78% of the cork discs decreased to values below limit of detection (0.49 ng/L; TCA initial concentration between 0.5 and 2 ng/L). By immersing the discs' in a saline solution for 24 h prior current application, the TCA removal was improved by 10–15%. When the 34 cork discs contaminated with 2.5 times-fold more TCA were subjected to EC after 24 h immersion in the saline solution, the percentage of discs in which TCA concentration was below 0.49 ng/L decreased to 41%. Still, and considering that TCA perception threshold in wines starts at 1.5 ng/L, 85% of the cork discs exposed to EC reatment presented TCA levels below the threshold. Results showed that the here developed EC system could be a viable method for the removal of TCA from cork discs. [ABSTRACT FROM AUTHOR]

Graphical abstract Highlights • Simultaneous saline solution and dehydrated sludge desalination were achieved. • The D salt of anodic sludge reached 31.63 ± 1.26% after 200 d operation. • Dehydrated sludge degradation rate was up to 32.70 ± 1.67% after 200 d. • The humic acid and available nutrient contents in dehydrated sludge all increased. • The heavy metals in dehydrated sludge could be transferred into the stable form. Abstract The invention of solid phase bioelectrochemical systems (SPBESs) provides a promising method for synchronous dehydrated sludge compost, desalination and bioelectricity generation. However, low power density and anodic salinization are common problems in SPBESs. A two-phase microbial desalination cell (TPMDC) could achieve simultaneous desalination of saline solution and dehydrated sludge by adding concentration chambers. Experimental results indicated that the D salt in 3 d for different concentration saline solutions were 6.00 ± 0.05% (35 g L−1), 10.75 ± 0.76% (10 g L−1), and 19.80 ± 0.64% (2 g L−1) respectively during the stable operation period of TPMDC. The D salt of anodic sludge reached 31.63 ± 1.26% after 200-day operation, and the removal of organic matter was up to 32.70 ± 1.67%. The P max (1.97 ± 0.33 W m−3) was produced on 52 d with open circuit voltage (OCV) of 0.998 ± 0.011 V. After bioelectrochemical stabilization, the feasibility of dehydrated sludge land application was improved. Specifically, the dehydrated sludge humication level significantly enhanced, the contents of available nitrogen, phosphorus and potassium all increased, the heavy metals and metalloids in dehydrated sludge transferred into stable residual form, and phytotoxicity of dehydrated sludge decreased. BES as a pretreatment of dehydrated sludge composting has great potentials. [ABSTRACT FROM AUTHOR]

[Display omitted] • A salt-tolerant polyelectrolyte hydrogel was fabricated. • Mutual interactions of adjacent cations and aromatic rings endow the hydrogel with salt-tolerant properties. • The composite gradient hydrogels present enhanced adsorption and catalytic performance. • The gradient hydrogel matrix demonstrates good stability and reusability used in the saline solutions. The integration of nanostructured materials into hydrogel matrix with chemical gradient holds great promise in gathering the pollutants and enhancing their adsorption or photocatalytic performance. However, the electric potentials rooting in the common gradient polyelectrolyte hydrogel are almost completely shielded by the co-existing counter-ions. In this study, a salt-tolerant gradient polycationic electrolyte hydrogel was fabricated by free radical copolymerization under the induction of unilateral UV illumination, which was used as nanofillers matrix. The cation-π interactions between the adjacent cations and aromatic rings endow the gradient polycationic electrolyte hydrogels deserving the salt-tolerant properties. Thus, the build-in electric potentials are still reactive on enrichment of the anionic heavy metals in highly concentrated salt solutions, altering the defects of the common gradient polyelectrolyte hydrogel. Using Sb(V) adsorption and Cr(VI) photocatalytic reduction as target reactions, the gradient composite hydrogels always display fast and high removal capacities towards these anionic pollutants in the saline solutions of 500 mM, as well as good stability and reusability. This salt-tolerant hydrogel matrix provides a smart material platform with self-driven forces in the fields of pollutant enrichment and removal. [ABSTRACT FROM AUTHOR]

[Display omitted] • Diglycolic acid is firstly installed into PBT backbone. • PBDTs show good mechanical properties with high elongation at break and strength. • PBDTs behave improved degradability in bio/seawater degradation. • PBDT50 exhibited the fastest degradation among reported marine degradable polymers. • Modified with traces of Ag@AgCl, PBDTs obtain enhanced antibacterial activity. Marine plastic pollution is a worldwide challenge making new progress in the field of degradable polymers necessary. However, it is difficult for commercial biodegradable polymers, such as polylactide (PLA), to realize rapid degradation in seawater by simply blending modification. Here, we prepared a novel series of poly(butylene diglycolate/terephthalate) (PBDT) copolymers by introducing diglycolic acid into PBT. The proposed polyesters can serve as an eco-friendly substitute for existing packaging materials. The mechanical property of PBDTs, with high tensile strength (>23.4 MPa) and elastic modulus (95–610 MPa), had advantages compared with commercial degradable polymers. The hydrophilicity is enhanced with ether bonds of butylene diglycolate (BD) segments. And the hydrolysis of copolymers was accelerated in seawater, showing 16% weight loss after 30 days. Moreover, PBDTs with BD segments ≥ 20% performed great degradability in Phosphate Buffered Saline and enzymatic solution. And their degradation mechanism was monitored through various tests such as 1H NMR, SEM and GPC. With a small number of antibacterial agents, such as 8% mass fraction of chitosan nanoparticles (CHNPs) or 1.0% of Ag@AgCl, PBDT composites could obtain good antibacterial ability for Gram-negative Escherichia coli without sacrificing the thermal, mechanical properties of the parent PBDT50. This work provides insights and direction for the development of seawater degradable polymers and thereby is able to relieve additional marine pollution in the future. [ABSTRACT FROM AUTHOR]

A novel bio-entrapped salt marsh sediment membrane reactor (BESMSMR) was evaluated for treating high-salinity pharmaceutical wastewater, and membrane fouling behaviour was also assessed. The BESMSMR was operated in parallel with a conventional membrane bioreactor (CMBR), and a salt marsh sediment membrane bioreactor (SMSMBR) as well as an entrapped biomass MBR (bio-entrapped membrane reactor, BEMR) to facilitate a meaningful comparison of performance characteristics obtained in these reactor systems. Two hydraulic retention times (HRTs) of 60 and 40 h with organic loading rates (OLRs) varied from 7.0 to 11.9 kg COD/m 3 d were tested. The pharmaceutical wastewater used has an average total chemical oxygen demand (TCOD) of 17,931 ± 1851 mg/L and total dissolved solids (TDS) of 20,881 ± 2030 mg/L. The BESMSMR demonstrated the highest removal efficiencies of TCOD (78.4–81.3%), due to the ability of the marine sediment microorganisms seeded from coastal shores to thrive in the hyper-saline environment and degraded recalcitrant organic matter present in the pharmaceutical wastewater. The anoxic zone presented in the inner part of bio-carriers could have triggered the denitrification reaction, and thus improved the TN removal rate by 15–20%. Membrane fouling was reduced with lower concentrations of mixed liquor suspended solids (MLSS), extracellular polymeric substance (EPS), and soluble microbial products (SMP) in the entrapped biomass MBRs. Proteins rather than carbohydrates were the main component of EPS and SMP in the MBR systems. The novel BESMSMR possesses the benefits of salt marsh sediment and an entrapped biomass technique that offered effective organic removal for the high-salinity pharmaceutical wastewater and reduced membrane fouling. [ABSTRACT FROM AUTHOR]

The objective of this study was to obtain a natural coagulant from the Moringa oleifera seed that was able to reduce the contamination of surface water with initial turbidity of 75 NTU without increasing the organic material in the water treated. The parameters evaluated were color, turbidity and compounds that absorb light UV 254nm , dissolved organic carbon (DOC) and reduction of specific absorption of UV 254nm (SUVA). For this we used the saline and aqueous extraction processes of coagulant followed by ultrafiltration. In this work the dosage of coagulant was used in terms of concentration of protein coagulant, allowing greater reproducibility and reliability of results. The saline coagulant had a better performance in the removal of color (89.15%), turbidity (88.75%) and compounds with UV 254nm absorbance (75.93%), with low DOC concentration in the treated water and with 38% less SUVA concentration, when compared to that by surface water. A decrease in the volume of the concentrated coagulant needed for such results should be underscored. In fact, only one half of the volume was required when compared to non-ultrafiltrated coagulant. The above directly affected DOC in the treated water which was less for concentrated saline coagulant (4.01 mg/L) when compared to non-concentrated saline coagulant (8.39 mg/L). High efficiency in water treatment, reduced volume of coagulant and decreased concentration in organic matter in the treated water, especially with regard to SUVA, open new perspectives in the use of saline coagulant of M. oleifera as a natural coagulant for the treatment of supply water. [ABSTRACT FROM AUTHOR]

Biological treatment of hypersaline effluents with high organic matter concentrations is difficult to carry out and it can require a long start-up phase. This is the case of the treatment of fermentation brines from the table olive packaging (FTOP) industries. These effluents are characterized by conductivity values around 90 mS/cm, COD around 15,000 mg/L and total phenols concentration around 1000 mg/L. In this work, FTOP has been treated in two sequencing batch reactors (SBRs) operated in parallel. In each SBR a different start-up strategy has been carried out. In the SBR-2, biomass was previously acclimated to high salinity using simulated wastewater without phenolic compounds, meanwhile in the SBR-1, FTOP was added from the beginning of the start-up. Results indicated more operational problems in the SBR-2 consisting in a higher deflocculation that drove to high turbidity values in the effluent. Besides, at the end of the start-up, the SBR-1 reached higher COD removal efficiencies than SBR-2 (88% and 73%, respectively). In both reactors, an increase in γ- Proteobacteria in the microbial population was observed for increasing conductivities. In addition, phenols were completely removed in both reactors at the end of the start-up, what implied very low toxicity values in the effluent. [ABSTRACT FROM AUTHOR]

Highlights: [•] Valorisation of aluminium saline slags as adsorbents. [•] Chemical activation of saline slags. [•] Activated saline slags as adsorbents of heavy metal ions from aqueous solutions. [Copyright &y& Elsevier]

Abstract: This study focused on the characterization of fouling cake layer during operation of a membrane bioreactor system employed for the treatment of synthetic hypersaline oily wastewater. Also the effects of ultrasound and addition of four types of flocculants (aluminium sulfate, Chitosan, ferric chloride, polyaluminium chloride) on mitigation of membrane fouling were studied. The components of the foulants were examined by Fourier transform infrared (FTIR) spectroscopy, scanning electron microscopy (SEM), atomic force microscopy (AFM), energy dispersive X-ray (EDX) analysis, inductively coupled plasma (ICP) and particle size analyzer (PSA). The FTIR demonstrated that membrane fouling layer is governed by the deposition of organic and inorganic substances composed of extracellular polymeric substances (EPS) (proteins, polysaccharides, etc.), hydrocarbon components and inorganic matters. The AFM images of the fouled membrane confirmed the idea of surface coverage as a fouling mechanism. The SEM analysis showed that rod-shape bacterial clusters were one of the contributors to membrane cake layer. The EDX and ICP results showed that Mg, Al, Ca, Na, K and Fe were the major metal elements in the fouling cake. The PSA results indicate that membrane foulants had a much smaller size than mixed liquor suspensions in the MSBR. Fouling mitigation experiments showed that the effect of organic flocculant was more than inorganic chemicals but the overall effects were not significant. Ultrasound could effectively remove the fouling cake from the membrane surface and thus recovered the membrane permeation flux for a long time. [Copyright &y& Elsevier]

Abstract: This work presents the biosorption potential of Fennel biomass for the effective removal of Cd(II) ions. The biosorption was maximum (92%) at pH 4.3. Maximum biosorption capacities of Cd(II) at 30, 40 and 50°C temperatures were 21, 24 and 30mg/g, respectively. The biosorption of Cd(II) was concentration dependent and increases from 0.49 to 9.3mg/g with increase in concentration from 5 to 100mg/L. Biosorption follows Freundlich isotherm at 50°C. Mean free energies at different temperatures were in between 7.1 and 11.95kJ/mol indicating chemical nature of biosorption process. Kinetics studies showed that pseudo-second-order kinetics model was applicable to the data. The process was endothermic and spontaneous, the spontaneity of the process increases with increase in temperature. Regeneration studies showed a decrease in the recovery of Cd(II) from 99.8% to 41.7% in five consecutive cycles. 80% of the Cd(II) in single and multi-metal systems was recovered in 10mL. Breakthrough and exhaustive capacities of Cd(II) in single metal system were 10 and 40mg/g. For multi-metal systems in double distilled water the breakthrough and exhaustive capacities of Cd(II) were 2 and 12mg/g. In saline solution the breakthrough and exhaustive capacities of Cd(II) were 0.8 and 4mg/g. [Copyright &y& Elsevier]

[Display omitted] • Injectable MOGs were developed at room temperature via phase transfer strategy. • The MOGs allow programmable encapsulation and pH-responsive drug release. • Saline-mediated synthesis of high-strength MOGs were obtained for hemostasis. • Drug-loaded MOGs suppressed tumor growth by a synergetic effect. Metal-organic hydrogels (MOGs) are emerging as alternatives to metal–organic frameworks owing to advantages such as porous microstructure and flexibility, particularly in the biomedical field. In this work, injectable MOGs were developed at room temperature with zinc ions as the metal nods and 4,5-imidazole dicarboxylic acid as the organic ligand modulator by a phase-transfer strategy. The resulting MOGs enabled the programmable encapsulation and pH-responsive release of various water-soluble and water-insoluble drugs, and biomacromolecules. The prepared MOGs exhibit a microporous nanofibrous structure with low mechanical strength, and shear-thinning, injectable, and self-healing properties. Notably, high-mechanical strength self-supporting hydrogels were obtained after injection into a saline solution. This resulted in the rapid hemostatic effect of the prepared MOGs in different surgical animal models. To illustrate their drug delivery applications, doxorubicin and glucose oxidase were encapsulated into the MOGs, demonstrating the glucose–pH dual-responsive release. The drug-loaded MOGs efficiently suppressed tumor growth by the synergetic effect of tumor vascular obstruction, nutrition starvation, and chemotherapy. The injectable MOGs with controllable rheological and drug-carrying properties have promising potential for drug delivery and other biomedical applications. [ABSTRACT FROM AUTHOR]

[Display omitted] • Original positively-charged copolymers are synthesized. • Positively charged membranes are formed by dual-bath procedure. • Bacteria killing occurs upon contact with the membrane's surface. • Membranes can be regenerated by washing with saline solution. • Membranes can kill while rejecting bacteria. This work reports the synthesis of a unique positively-charged copolymer obtained from the reaction between iodomethane and a random copolymer of styrene and 4-vinylpyridine. This copolymer, referred to as qP(S- r -4-VP), was fully characterized by 1H NMR, FT-IR, XPS and GPC, and then mixed with poly(vinylidene fluoride) (PVDF) to form porous membranes able to kill bacteria upon contact. Membranes were prepared by a dual-bath procedure using methanol (10 min) and water (24 h). They exhibited typical bi-continuous structure with large pores (mean pore flow diameter: 0.2–0.45 µm) that decreased with the copolymer content, and large porosity (77%-80%). The presence of the copolymer on the membrane surface was ascertained by FT-IR. All membranes exhibited a high water contact angle in air (>140°), but hydration capacity was enhanced with the copolymer content in the membrane (from 10 mg/cm3 for the virgin membrane up to 225 mg/cm3 for modified membranes). The surface charge of the membrane increased with the copolymer content. Q3 membrane (containing 3 wt% copolymer) was selected as the best membrane able to kill various bacteria including Escherichia coli , Stenotrophomonas maltophilia and Staphylococcus epidermidis. Besides, washing with a saline solution of sodium citrate or sodium hexametaphosphate disturbed electrostatic and hydrophobic interactions between dead bacteria and membrane surface, making bacterial release possible. Membrane regeneration properties were also demonstrated from multiple killing/release cycles. Finally, it was shown that membranes were able to kill bacteria during a dead-end filtration process, while achieving 100% rejection. The material and membrane presented in the frame of this work could be of interest to decrease the pathogenicity of a feed during separation [ABSTRACT FROM AUTHOR]

[Display omitted] • Optimization of nitrogen doped carbon dots with dual emission. • Stability was verified in saline solution and 800 min of continuous UV excitation. • Proposed CDs showed excellent selectivity towards acetone, Cr (VI) and Fe (III). • CDs reveal outstanding acetone sensing in commercial products and urine samples. • Optical sensing of Cr(VI) is accompanied by its reduction to Cr(III). A simple, sustainable and cost-effective fabrication technique for obtaining stable and multifunctional nanoprobes has been a challenging task for the scientific community. In this report, we optimized the fabrication conditions to obtain dual-emissive carbon dots (DECDs) using simple one-step synthesis. The optimization of the actual conjugation length, dopant concentration, and the amount of surface functional groups could be seen in the form of intriguing characteristics of DECDs. Apart from being highly stable under continuous UV excitation, extensive range of pH, wide temperature range and saline solution, the proposed nanoprobes revealed efficient fluorescence in the complete visible range at a certain excitation wavelength, which was found to be favorable for selective ratiometric optical sensing of acetone, Cr(VI) and Fe(III). The sensing performance of carbon dots (CDs) for acetone was additionally verified in commercial products and spiked urine samples. Although the sensitivity of the probes for Cr (VI) and Fe (III) in spiked tap water samples was found to be comparable with the available techniques, the added advantage of the label-free reduction of highly toxic Cr(VI) to relatively less toxic Cr(III), makes the proposed nanomaterial more viable and effective for contaminated/waste water treatment. The proposed scalable strategies have potential applications in water purification and the possible development of economically viable portable ketone testing kits. [ABSTRACT FROM AUTHOR]

• First investigation of salt effects on lift coefficients. • Simultaneous bubble and liquid velocity determination. • Contamination effects of NaCl on bubble shape and slip velocity. • Evaluation of hydrophobic tracer particle effects on the bubbles. The lift force is known to strongly influence the lateral bubble distribution in bubbly flows and is therefore an important force that has to be modeled in corresponding CFD simulations. For ellipsoidal bubbles, which are mostly present in industrial cases, the strength as well as the direction in which the lift force acts is thought to be determined by the bubble deformation. The bubble deformation however, can strongly be reduced when surface-active contaminations like salts are present in the liquid bulk, which implies a change of the lift force by contaminations too. In the present work, lift coefficients for single bubbles rising in aqueous NaCl solutions were determined to investigate the influence of such an inorganic surfactant on the lift force. For this purpose, a recently developed method by Ziegenhein et al. (2018) [50] is used, which is capable to measure the lift force in low viscous liquids. Besides the lift force, the bubble shape and slip velocity were studied in detail to connect the results to known contamination effects, which showed different behavior in dependence on the salt concentration. The results reveal that the contamination level plays an important role on changes of the lift force in comparison to clean bubbles. Up to a concentration of 1.0 mol/l the salt has only a weak effect on the lift force of larger bubbles. The lift coefficients of smaller bubbles however, clearly show significant changes, which were also reflected in a change of the bubble shape. However, some findings could only be connected to the slip velocity, which implies a connection of the lift force to more than just the shape. [ABSTRACT FROM AUTHOR]