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The need for sustainable and reliable decontamination methods is driven by concerns regarding antibiotic resistance, as well as environmental and cost-efficiency challenges associated with traditional methods. Plasma-activated water (PAW) holds significant promise as an innovative and eco-friendly decontamination method. Nevertheless, prior to industrial implementation of PAW-based decontamination devices, a deep understanding of the bacterial inactivation mechanisms and its interplay with PAW chemical composition is required. Advancing in this field requires interdisciplinary and collaborative research using standardized practices with cost-effective and shareable PAW reactors that are still missing today. Here, to this end, a portable PAW reactor, featuring a surface dielectric barrier discharge (SDBD) that operates in air, is presented. The gaseous and aqueous phases were chemically characterized by Fourier transform infrared (FTIR) absorption spectroscopy and vis-spectrophotometry, respectively. To assess PAW antimicrobial efficacy Escherichia coli was employed as a model organism on six different PAW samples for three different treatment times. The significance of water recirculation in controlling the chemical composition of PAW, altering the nitrogen species balance in favor of NO 2 − , is demonstrated. This chemical modification consequently enhanced the antimicrobial effectiveness of PAW, reaching a log reduction of ∼ 6. Exposing E. coli to equivalent concentrations of RONS to those found in PAW attained similar log-reductions, indicating that acidified nitrites are key to PAW antimicrobial activity. Through an innovative and portable design, this study illustrates the crucial role of water recirculation in tailoring PAW composition, leading to improved decontamination capabilities and establishing a key parameter for further optimization of PAW production. • Plasma-Activated Water (PAW): a sustainable and innovative decontamination method. • PAW portable reactor design for in situ applications and collaborative scientific research. • Water recirculation significantly impacts PAW composition for improved decontamination. • Acidic conditions are essential for the antimicrobial activity of reactive nitrogen species in PAW. [ABSTRACT FROM AUTHOR]

[Display omitted] • mAg 3 PO 4 @g-C 3 N 4 /PDS/Vis enhance CBZ degradation rate by 3.6-fold. • 87.15 % mineralization of CBZ was achieved in 30 min via mAg 3 PO 4 @g-C 3 N 4 /PDS/Vis. • 1O 2 -dominated ring-opening is identified to be key for improved mineralization. • Multiple PhACs in the effluent are simultaneously degraded with high mineralization. The wide occurrence of pharmaceutically active contaminants (PhACs) in aquatic environments has received more and more concern owing to the associated high risks to ecosystems. Even worse, conventional wastewater treatment techniques fail to provide effective decontamination for these emerging contaminants. Herein, we designed and constructed mAg 3 PO 4 @g-C 3 N 4 heterojunction for a persulfate-assisted photocatalytic system (mAg 3 PO 4 @g-C 3 N 4 /PDS/Vis) for the rapid and effective degradation of PhACs. Superior mineralization of CBZ (87.15 %) was achieved within 30-minute treatment with mAg 3 PO 4 @g-C 3 N 4 /PDS/Vis, exhibiting 11-fold enhancement compared to mAg 3 PO 4 /Vis system. Integrating experimental investigations with theoretical calculations, singlet oxygen (1O 2) was identified as the key reactive species, while the 1O 2 -dominated ring-opening pathway contributed significantly to the high mineralization of CBZ. Moreover, mAg 3 PO 4 @g-C 3 N 4 /PDS/Vis showed robust degradation performance of multiple PhACs across various water matrices. Multiple PhACs could be simultaneously degraded with high mineralization efficiency in the wastewater effluent, demonstrating the promising application of mAg 3 PO 4 @g-C 3 N 4 /PDS/Vis for decontaminating emerging contaminants in wastewater treatment. [ABSTRACT FROM AUTHOR]

[Display omitted] • Fabricated a Janus lamellar membrane (JLM) with asymmetric bi-layered structure. • A vital advantage of JLM based on BiOCl is its ease of mass transfer and flotation. • Optimize the weight ratio of BiOCl/CNFs and BiOCl/CNFs@CNTs in JLM to 1:1. • JLM integrates photocatalytic H 2 evolution, decontamination and water evaporation. • The photothermal water evaporation rate of JLM attains a level of 1.92 kg·m−2·h−1. Photocatalysis and photothermal water evaporation (PWE), as two technologies that utilize solar energy, have received special attention in the context of carbon neutrality. It is undoubtedly attractive if a structure can effectively combine the two technologies. However, it remains a huge challenge to simplify structural design while improving energy efficiency and mass transfer. Herein, a Janus lamellar membrane (JLM) with an asymmetric bi-layered structure was constructed using facile vacuum filtration. Specifically, the top layer consists of BiOCl nanosheets (BNs) and cellulose nanofibers@carbon nanotubes (CNF@CNT), forming a functional layer that facilitates solar energy utilization. Within the top and bottom layers, CNF@CNT and CNFs are respectively embedded into the interlayer space formed by stacked BNs, offering abundant nanochannels for continuous and rapid water supply. Moreover, as the weight ratio of the BN-CNF@CNT and BN-CNF precursors is optimized to 1:1 with the BN-CNF@CNT layer facing light source, the photocatalytic hydrogen evolution (PHE) rate of JLM reaches up to 39.81 μmol·g−1·h−1, corresponding to approximately 3.12 and 1.57 times that of the BN-CNF and BN-CNF@CNT lamellar membranes, respectively. Importantly, the PHE rate remains consistent within ten cyclic stability experiments. Furthermore, the PWE rate of JLM achieves 1.98 kg·m−2·h−1 under 1.0 solar irradiation (100 mW·cm−2). A vital advantage of the JLM is its ability to float on the liquid surface, enabling concurrent photocatalytic decontamination and PWE processes. The research on designing JLM with an asymmetric structure for both photocatalysis and PWE provides a practical approach to the comprehensive utilization of solar energy. [ABSTRACT FROM AUTHOR]

[Display omitted] • The enol-bound ZnAl-LDH effectively tunes the electronic structure. • The ACLDH/PMS/Vis system enables efficient treatment of tetracycline hydrochloride, leachate and E. coli. • A direct oxidative degradation mechanism is proposed for the ACLDH/PMS/Vis system. • ACLDH material is an environmentally friendly and highly efficient photocatalyst. The direct oxidative transfer process (DOTP) is a novel degradation-mineralisation system for the treatment of organic trace contaminants in water pollution, which are present with extremely high energy and/or chemical additions as well as large residues due to partial mineralisation. In this study, an enol-conjugated LDH (ACLDH) catalyst capable of interacting with persulfate was used, and tetracycline hydrochloride (TC) was degraded under visible light irradiation, and experimental and theoretical results showed that the ACLDH catalyst efficiently regulated its electrons. Under optimal experimental conditions, the ACLDH material acted as a catalyst to activate and stabilise the DOTP process on the surface of the nanocatalyst, resulting in the complete removal of TC within 35 min with up to 25 % mineralisation. In addition, the study investigated the effects of starting pH, catalyst dosage, several common inorganic anions and humic acid on TC removal. DOTP based on the ACLDH/PMS/Vis system is a very promising nanotechnology for water purification with strong performance in real waste leachate (up to 12 % TOC mineralisation) and disinfection applications. [ABSTRACT FROM AUTHOR]

• Efficient molecule enrichment across a dynamic water-water interface. • Robust hydrogel polymeric backbone allows for efficient pollutant arrestment. • Magnetically actuated spinning concentrates pollutants rapidly by ≥300-fold. • Ultrasensitive colorimetric monitoring for reliable water chemistry analysis. • Energy and time-efficient while preserving innate chemical properties of pollutants. The efficient accumulation of molecules from dilute solutions is crucial for facilitating pollutant decontamination, trace analyte detection, and chemical reactions. However, current methods to concentrate molecules are limited by prolonged processing times, high energy consumption, and a narrow range of applicable molecules. Herein, we introduce a magnetic-responsive spinnable hydrogel marble (SHM) as a miniature molecule concentrator for efficient water decontamination and sensing applications. The spinning motion of SHM creates a dynamic water-water interface within an aqueous environment, generating a vortex-like hydrodynamic flow that actively delivers molecules into the embedded hydrogel microdroplet. Notably, the SHM achieves a remarkable ∼95 % decontamination efficiency for cationic organic water pollutants in just 15 min while simultaneously concentrating molecules within SHM by ≥300-fold, a feat that remains challenging with conventional non-dynamic liquid interface. Moreover, the SHM also doubles as a versatile concentrator-cum-detection platform for ultrasensitive colorimetric sensing of organic pollutants in real wastewater at >99 % accuracy, thereby allowing the on-site readout of water chemistry using naked eyes or smartphone for prompt intervention. By enabling the efficient and swift concentration of molecules in an energy-efficient manner, our unique design effectively addresses the drawbacks of traditional approaches and creates enormous opportunities for diverse analytical, environmental, and chemical applications. [ABSTRACT FROM AUTHOR]

[Display omitted] • The fabrication methods of MOF/synthetic polymers monoliths (MMSPs) are introduced. • The applications of MMSPs for water purification are summarized. • The approach to compensating limitations of MMSPs fabrication are recommended. • The perspective of MMSPs for water treatment are proposed. Recent years have witnessed significant development of metal–organic frameworks (MOFs) for versatile applications, especially for water decontamination. However, it is of difficulty to apply MOFs-based materials to actual water treatment owing to the fragile powder pattern. Fortunately, the synthetic polymers with bulk macroscopic structure bear desirable process accessibility in industrial production, which are favorable for MOFs' immobilization to broader applications in water decontamination. In this critical review, we summarized and discussed the design strategies as well as fabrication methods of macroscopic MOFs-based materials/synthetic polymers (MMSPs). Meanwhile, the studies regarding potential applications to real water systems over MMSPs are introduced. Finally, the future challenges and perspectives of MMSPs for practical water purification are proposed. [ABSTRACT FROM AUTHOR]

[Display omitted] • Efficient 1O 2 nanogenerator was precisely constructed by regulating Fe spin state. • Low spin-state Fe induced nonradical conversion from H 2 O 2 to 1O 2. • The 1O 2 -dominated system selectively removed low ionization potential contaminants. • Stable Fh/BiOI transformed high-toxic contaminant into low-toxic products. • Fh/BiOI exhibited excellent mineralization performance towards secondary effluent. The hydrogen peroxide (H 2 O 2)-based photo-Fenton-like was a promising technology for the generation of singlet oxygen (1O 2), which was highly desirable in water purification. However, the yield of 1O 2 in traditional radical system was low due to the radical competition. Targeted construction of the non-radical system could solve the above issue, but it has been a challenge. In this study, we targetedly regulated the Fe spin state to efficiently generate 1O 2 in a nonradical path. The experimental and theoretical results demonstrated that low-spin FeIII enhanced H 2 O 2 adsorption, directly extracted electrons from H 2 O 2 to Fe center, and rapidly cleaved O–H bond to accelerate the recombination of *OOH with H 2 O 2 for efficient 1O 2 generation. This unique nonradical process differed obviously from the traditional radical pathway for 1O 2 generation. The developed 1O 2 -dominant 50Fh/BiOI/H 2 O 2 /vis system degraded 98.4% of TCH, which was higher than that in •OH-dominant Fh/H 2 O 2 /vis system (84.2%) and it had excellent resistance to various substances, including inorganic ions, dissolved organic matter and real water matrix (tap water and secondary effluent). This study enhanced our understanding of spin-state-dependent photo-Fenton-like reaction and inspired the targeted development of a new-generation selective wastewater treatment technology. [ABSTRACT FROM AUTHOR]

[Display omitted] • The conversion of inert H* abs into reactive H* ads was achieved by introducing S element. • H 2 O reduction into H* ads significantly contributed to DTA degradation by S-nZVI. • S-nZVI enhanced H* ads retention by forming S-H* ads bonds on the S sites. • S-nZVI improved the accumulation of H* by inhibiting H 2 evolution. Sulfide-modified nano zerovalent iron (S-nZVI) has garnered considerable attention in water decontamination due to its exceptional reactivity. However, there is still limited knowledge regarding the importance of different atomic hydrogen species (i.e., absorbed H* and adsorbed H*) in S-nZVI-mediated reductions, as well as the role of sulfur in regulating the catalytic performance. Therefore, we systematically characterized H* during the reaction of S-nZVI by the cyclic voltammetry (CV) analysis and electron paramagnetic resonance (EPR) spectroscopy, whereas nZVI and palladized nZVI (Pd-nZVI) were used as the reference. H* originating from the reduction of H 2 O molecules would recombine to H 2 or be absorbed into the Fe crystal lattices forming inert absorbed H* (H* abs) on nZVI. In contrast, S-nZVI significantly boosted the accumulation of relatively reactive surface-adsorbed H* (H* ads). Consequently, S-nZVI exhibited the promoted degradation of diatrizoate (DTA), a kind of H* ads -sensitive contaminant. The increased solvent kinetic isotope effect (SKIE) value for DTA degradation by S-nZVI demonstrated that the reduction of H 2 O into H* ads played a significant role in the reaction. Raman spectroscopy and 1H nuclear magnetic resonance (1H NMR) further offered compelling evidence that S-nZVI preferred to stabilize H* ads by forming S-H* ads bonds on the surficial S sites, leading to the shift in the relative abundance of H* abs and H* ads. This study provides direct evidence for the identification of H* species in the S-nZVI system, and elucidates the fundamental mechanism of the enhanced H* ads retention resulting from the sulfidation of nZVI, inspiring the future optimization of S-nZVI for accelerating the reductive degradation of contaminants. [ABSTRACT FROM AUTHOR]

• A comprehensive literature survey on EF at neutral and near-neutral pH are presented. • Different supported and suspended catalysts used to widen the working pH are reviewed. • Recent advances on cathode modification methods in broadening EF pH are summarized. • Current application of chelating agents to increase the EF working pH are reported. • The prospects and challenges of EF process at neutral pH are addressed. One of the greatest engineering challenges of this century is development of new technologies for removing emerging hazardous contaminants from water sources. Electro-Fenton (EF) as one of the most promising approaches of advanced oxidation processes (AOPs) has received widespread attention for its excellent performance in the removal of recalcitrant pollutants due to generation of strong oxidizing species like hydroxyl radicals (OH). However, the practical application of classical homogeneous EF process is hampered by a narrow pH range (2–4) and production of sludge at higher pH values. The information obtained so far highlights the need to enhance the removal efficiency and reduce the reaction time of EF process under neutral pH conditions. Herein, this review summarizes efficient approaches in recent years (2017–2023) applied in EF system with the aim of overcoming the low pH implementation barrier, such as application of heterogeneous catalysts in EF process (HEF), cathode modifications, using chelating agents, and hybridizing the EF with other treatment methods, including adsorption, membrane, and photo/catalysis. These strategies can accelerate the iron cycle and Fe3+ reduction; therefore, more H 2 O 2 and OH can be generated. Promoting the H 2 O 2 utilization efficiency can provide more oxidative species, which leads to higher degradation and mineralization of contaminant. On the other hand, some strategies by preventing the Fe3+ precipitation at higher pH values help the system work in a wider pH range. In the final section, the challenges of these plans are discussed and perspectives for future research are proposed to improve the practicability and feasibility of the EF for wastewater treatment. [ABSTRACT FROM AUTHOR]

• Handy paper-like purifier with striking multifunctional water decontamination properties. • High loading of functional components onto bacterial cellulose via chemical bonds. • Superior adsorption capacities towards metal ions and organic dyes, and disinfection efficiency. • Simultaneous removal of multiple species from polluted water, and superior reusability. Contaminated water contains various types of pollutants, the removal of which requires two or more technologies. It is imperative but challenging to develop water purifier for simultaneous removal of multiple pollutants for the sake of easy operation, low cost, and etc. Previously reported multifunctional purifiers are normally nanoparticles which require caution during use. Here, we describe a design of paper-like multifunctional purifier, which has biomass-based structure by grafting polyethylenimine derived quaternary ammonium compounds onto three-dimensional bacterial cellulose substrate. Compared to similar materials reported previously, our product exhibited strikingly higher adsorption capacities towards various metal ions including Pb2+, Cu2+, and Cr6+, anionic organic dyes including congo red, methyl orange and methyl red, and excellent disinfection efficiency towards both Gram-negative and Gram-positive bacteria. Remarkably, this purifier also demonstrated effective removal of the three contaminative species simultaneously from both simulated and local polluted water. With more virtues of superior reusability and extreme handy convenience, we hope our molecular design could inspire further efforts on the rational construction of multifunctional water purifier with easy operation. We reckon our material to have strong potential for the possible use in water treatment, especially in regions that are short of environmental infrastructures. [ABSTRACT FROM AUTHOR]

[Display omitted] • A novel all-in-one wood-based hybrid hydrogel was designed and fabricated. • The integrated nanoarchitecture possesses wide-spectrum solar energy utilization. • The system demonstrates multifunctional applications in photocatalysis and water evaporation. • The enhanced performance is mainly attributed to the synergy of photocatalysis and photothermal effect. Elaborately designing multifunctional energy conversion materials is vital to promoting renewable energy conversion. Herein, we report a novel approach in which photocatalytic materials and photothermal components are embedded simultaneously into porous delignified wood to construct wood-based hybrid hydrogels for water decontamination, hydrogen generation and freshwater production. Well-designed all-in-one system elaborately interfaces hydrogen-evolving semiconductor CdS with MoSe 2 that functions as co-catalyst and also possesses photothermal effect to simultaneously drive the removal of pollutants, hydrogen production and solar steam generation with high efficiency. The multifunctional system demonstrates a hydrogen evolution rate of 9.7 mmol g–1 h−1 and a high solar evaporation rate of 1.92 kg m−2 h−1 with an energy conversion efficiency up to 90.7% under one sun illumination. The encapsulation of photothermal-assisted photocatalytic systems with hydrogels effectively prevents toxic volatile organic compounds (VOCs) from being evaporated without deteriorating the solar steam generation performance. This study provides new insights into the rational design of novel multifunctional materials for environmental remediation and energy sustainability. [ABSTRACT FROM AUTHOR]

[Display omitted] • The 1O 2 -mediated advanced oxidation processes (AOPs) have significant potential in wastewater treatment. • The physical and chemical properties, and reaction characteristics of 1O 2 are summarized. • 1O 2 can be produced by many pathways including direct catalytic and energy-assisted activation. • Multiple mature detection methods of 1O 2 are collected in this review. • The existing deficiencies and improvements of 1O 2 -mediated AOPs are discussed. Advanced oxidation processes (AOPs) have been widely used in contaminants decomposition to reduce their harm. Especially, the singlet oxygen (1O 2)-mediated AOPs have been considered a promising decontamination method due to their good ability to resist water matrix in actual wastewater treatment. However, there are still some doubts about the important role of 1O 2 in wastewater treatment. Therefore, it is necessary to comprehensively summarize the characteristics, detection methods, and generation pathways of 1O 2 based on the latest research. In this review, various characteristics of 1O 2 are comprehensively summarized, including its molecular structure, orbital energy, lifetime in solvents, reaction characteristics and reaction pathways. Next, the generation pathways of 1O 2 including catalytic ozonation, hydrogen peroxide, persulfate, periodate, photocatalysis, electrochemical, and peracetic acid activation systems are summarized. Additionally, 1O 2 can be detected by various methods such as fluorescence probes, chemiluminescence probes, quenching tests, electron paramagnetic resonance, deuterium oxide experiments, and product analysis. The combination of multiple detection methods can improve accuracy of 1O 2 detection. Finally, the existing deficiencies and improvements in mechanism exploration, detection means and practical application of 1O 2 are also contained. It is expected that this review can provide new inspiration for subsequent research on 1O 2 -mediated AOPs. [ABSTRACT FROM AUTHOR]

Graphical abstract Highlights • Large scale synthesis of ZnO tetrapods by flame transport synthesis. • Eco-friendly extraction of activated carbon from sugarcane. • ZnO tetrapods-activated carbon based advance composite fabrication. • ZnO tetrapods-activated carbon composites as efficient Cr(VI) adsorbents. Abstract Owing to its acute toxicity and mobility, the hexavalent chromium [Cr(VI)] in water and wastewater is an immense risk to the environment. Herein, ZnO-tetrapods/activated carbon (ZnO-T/AC) nanocomposite was synthesized as an adsorbent for an efficient decontamination of Cr(VI) from an aqueous medium. The tetrapodal ZnO was synthesized by flame transport synthesis (FTS) approach. The utilized activated carbon (AC) was successfully prepared from sugarcane bagasse with sodium hydroxide (NaOH) impregnation, followed by carbonization. Finally the ZnO-T/AC nanocomposite was synthesized by the hydrothermal method. The structural and chemical properties of the obtained nanocomposite (NC) were systematically characterized using X-ray diffraction (XRD) technique, scanning electron microscopy (SEM), X-ray photoelectron spectroscopy (XPS), Fourier transform infrared (FTIR) spectroscopy and Brunauer–Emmett–Teller (BET) analysis. Batch experiments were performed with the AC, ZnO-T and ZnO-T/AC to study their maximum adsorption efficiency for the Cr(VI). The effect of operational parameters such as contact time, pH and adsorbent dosage on the removal of Cr(VI) were also investigated. Different kinetic models were employed to comprehend the adsorption mechanism. The removal efficiency (97%) of Cr(VI) using ZnO-T/AC adsorbent was achieved at pH 2. The synthesized nanocomposite showed significant potential for the decontamination of Cr(VI) and can be further explored at a large scale for the efficient removal of hazardous heavy metal ions from the industrial contaminates. [ABSTRACT FROM AUTHOR]

In this study, a microwave-induced thermal treatment at relatively low temperature (300–350 °C) was introduced to the decontamination of polluted soils with high mercury concentration, in the interest of addressing the issues related to traditional thermal desorption methods i.e. high energy consumption, high cost, and irreversible damage to the soils. The addition of granular activated carbon (GAC) was found to significantly increase the heating rate and accelerate the decomposition of mercury pollutants. A total mercury (T Hg ) removal efficiency of 86.9% could be achieved at microwave irradiation of 400 W (ca. 350 °C) for 40 min with a GAC/Soil mass ratio of 3:15. Moreover, the mutual transformation of five mercury fractions in the soils was also investigated to reveal the decomposition procedure. The environmental risk of T Hg remained in the soils was largely reduced by increasing the percentage of inert fractions from 88.1% to 96.1%. Of special importance, microwave irradiation greatly favoured the electric discharges of GAC, which produced molecular heating resources with excessively higher temperature than the overall soils to realize low damage to soils. Meanwhile, the specific bulk heating mode reduced the temperature barriers to allow easy release of decomposed mercury vapours. Furthermore, GAC additives showed negligible changes during the whole decontamination process and the increase of soil amounts did not affect the heating rate evidently. These results were remarkably promising to provide fundamental information for practical scaling-up remediation of contaminated soils with high mercury concentrations at relatively low temperatures that could be both convenient and energy-efficient. [ABSTRACT FROM AUTHOR]

Decontamination of air or other gas streams loaded with low VOC concentrations is a prevalent task for adsorption using zeolites. Emphasizing the importance of adsorber selection, several zeolites varying in type, Si/Al ratio and provider were tested for toluene as representative organic target compound and water as adsorbate both in single and competing adsorption studies. In some cases, the toluene breakthrough is mainly caused by water-driven desorption. It was shown that for adsorption capacity, kinetics and competition behavior not only type and Si/Al ratio of the zeolite are important but also producer-specific parameters such as crystallinity, binder type and content which are usually not explicitly documented. This study offers a basis for the selection of adsorber materials for treatment of gas streams with significant water contents. [ABSTRACT FROM AUTHOR]

Photocatalysis is one of the dominant technologies used to enhance the efficiency of water decontamination with light-based treatments. However, the effectiveness of photocatalysts is usually limited by the irradiation conditions and the properties of the water matrix. In this work, we have demonstrated the capability of surface microlenses (MLs) as a clean technology for more efficient photocatalytic water decontamination. Random or ordered surface MLs were fabricated from simple polymerization of nanodroplets produced in a solvent exchange process. Both random microlenses (MLR) and microlenses array (MLA) could enhance the photocatalytic degradation efficiency (η) of four representative organic pollutants, including methyl orange (MO), norfloxacin (NFX), sulfadiazine (SFD), sulfamethoxazole (SMX), spiked in ultra-pure water, synthetic natural water, or real river water. By controlling the conditions of light treatment, η could be enhanced by up to 402%. The effectiveness of surface MLs was validated under both visible LED light and simulated solar light and for two photocatalysts zinc oxide (ZnO) and titanium dioxide (TiO 2). By reducing the concentration of the photocatalysts from 100 to 5 mg/L and the intensity of irradiation intensity from 1 Sun to 0.3 Sun, our findings suggest that the enhancement factor by MLs was higher at lower catalyst concentration, or at lower light intensity. Based on optical simulations and experimental results, we demonstrated that surface MLs optimize the light distribution and promote the formation of active species, which results in the enhancement of η. The use of MLs may serve as a novel strategy to improve the photocatalytic degradation of micropollutants, especially in places where the available light source is weak, such as indoors or in cloudy regions. Synopsis: MLs-enhanced photocatalysis degradation of organic contaminants in different water matrices. [Display omitted] • Surface MLs enhance photocatalytic degradation efficiency by up to 402%. • Green and highly tunable fabrication method of surface MLs. • Mechanisms of MLs-enhanced photocatalytic degradation with 3D optical simulations. • More improvement of degradation by MLs with less catalysts or weaker irradiation. • Verify the feasibility of MLs in improving decontamination in complex water matrix. [ABSTRACT FROM AUTHOR]

Band-gap regulation of photocatalysts has been turned out to be a very important approach to achieve high effective utilization of solar spectrum and obtain an optimal photocatalytic property. Herein, a novel iodide modified Bi 4 O 5 Br 2 photocatalyst with controlled band-gap position was successfully synthesized for the first time via a simple alcoholysis-hydrolysis method at room temperature. The band structure, optical absorption properties, photo-induced charges transfer/separation rate of the synthesized samples were characterized by UV-vis DRS, Mott-Schottky method, valence band (VB) XPS, electrochemical impedance spectra and photoelectric conversion spectra. The results demonstrated that the conduction band position of Bi 4 O 5 Br 2 continuously decreased from 2.46 eV to 2.16 eV, and then the visible-light response and photo-generated carrier separation changes took place. Owing to the higher visible-light absorption capacity, lower interfacial charge-transfer resistance, and more efficient separation of the photoinduced charges, the iodide modified Bi 4 O 5 Br 2 exhibited a higher visible-light activity than pure Bi 4 O 5 Br 2 for the photocatalytic degradation of Bisphenol A (BPA) and NO removal under visible light irradiation. Ultimately, the repeated photodegradation experiments of BPA displayed that the obtained sample is stable and resistant to chemical or photochemical corrosion. We believe such a simple and effective strategy could pave a new way for narrowing continuously the band gap of an existed photocatalyst to control the generation and recombination rate of photo-induced carriers. [ABSTRACT FROM AUTHOR]

The recent thrust in utilizing microbial electrolysis cell (MEC) has led to accelerated attention in environmental decontamination. One key factor that governs this process is electron transfer efficiency. In this study, neutral red (NR) is involved as electron transfer mediator to investigate whether it could contribute to MEC performance. Afterwards, influence of electrode material selection on NR addition system was also studied. The results indicate MEC with NR shows better electrochemistry activity, which means sulfate-reducing bacteria (SRB) can response to electron transfer mediator NR. Further study reveals graphite felt triggers a better synergy with NR to facilitate electron utilization efficiency of the system subsequently maintains bacteria metabolic activity for a longer time. Sulfate removal in this reactor reaches 79.0% with electron utilization efficiency of 54.2%. To explore the mechanism, electrode bioelectrochemical property, microorganism activity and community were investigated. Electrode morphology analysis confirms graphite felt affords abundant space for the growth of electroactive microorganisms especially SRB and promotes electron exchange through cooperating with NR, which fits in with electrochemical impedance spectroscopy (EIS) analysis. High-throughput sequencing analysis confirms improved reactor can fortify the population dominant of SRB in the community which greatly raises electron utilization efficiency of SRB. [ABSTRACT FROM AUTHOR]

[Display omitted] • Selective oxidation of organic pollutants over MOFs-based catalysts was reviewed. • The mechanisms of selective oxidation over MOFs-based catalysts were introduced. • The unique advantages of MOFs in selective oxidation were highlighted. Efficient decontamination from water have attracted global attention in recent years. Advanced oxidation processes (AOPs) are widely used for aqueous organic pollutants degradation for water purification. However, it still is great challenge to efficiently oxidize the trace micropollutants especially from sewage matrix containing complicated matters, which would consume the reactive species to inhibit the decomposition of the target contaminants. Recently, many researchers devoted to the selective oxidation to address the above-mentioned problem. Various environmental functional materials like metal oxides and carbonaceous materials have been applied as catalysts for selective organic pollutants oxidation. Among them, metal–organic frameworks (MOFs) and their composites/derivatives displayed huge potential due to their designable structure and excellent catalytic performance. This review presented the research progress of MOFs-based materials in selective oxidation toward aqueous organic pollutants, in which some examples were analyzed in detail to show their performances, mechanisms as well as influence factors. The unique advantages of MOFs-based materials for selective oxidation were also discussed. Finally, the challenges and prospects of MOFs-based environmental functional materials in selective oxidation from water were proposed. [ABSTRACT FROM AUTHOR]

[Display omitted] • KMnO 4 oxidation can be activated by several strategies. • KMnO 4 oxidizes sludge and contaminants via inducing RMnS and free radicals. • Pollutants removal and sludge dewatering can be improved by in-situ produced MnO 2. • KMnO 4 -based AOPs can prominently enhance sludge dewatering and resources recovery. • KMnO 4 -based AOPs can prevent biogenic sewer corrosion and sludge-induced risks. The wastewater pollution with various contaminants exposure and increased sludge production from municipal wastewater treatment plants (WWTPs) are the two challenges confronted by human beings. Therefore, the pollution control and sludge treatment have gained growing attentions. Potassium permanganate (KMnO 4), as a green and non-toxic oxidant, has been largely employed in wastewater and sludge treatments, including pollutants removal, decrement of hazardous gas footprint, and improvement of sludge dewatering and resource recovery ascribed to its strong oxidability and excellent properties, which provides solutions for wastewater decontamination, risk mitigation and sludge recycling. The recent studies of KMnO 4 -based advanced oxidation processes (AOPs) in terms of wastewater and sludge treatment are comprehensively outlined in this review. Particularly, methods of enhancing KMnO 4 oxidation are summarized, and the application and relevant mechanisms of KMnO 4 -based AOPs in improving contaminants removal, sludge dewatering and resource recovery (i.e., short-chain fatty acids and methane) are illuminated and discussed. Finally, the knowledge gaps and new opportunities of KMnO 4 -based AOPs in wastewater and sludge fields are prospected. The review can promote an in-depth understanding of KMnO 4 -based processes and provide a theoretical framework for KMnO 4 application in wastewater and sludge managements. [ABSTRACT FROM AUTHOR]

Novel Zr 4+ and Ge 4+ co-doped titanium dioxide (Zr–Ge–TiO 2 ) nanoparticles for photocatalytic degradation of Chemical Warfare Agents (CWAs) were prepared via a homogeneous precipitation method. Considering the volatilization of solvents, solubility to CWAs, and compatibility with sensitive equipments, hydrofluoroether (HFE) was first used as the dispersion solvent of suspension decontaminants. Here, Zr (5.02 wt%)–Ge (0.94 wt%)–TiO 2 with the specific surface area of 447.9 m 2 g −1 exhibited the best photocatalytic performance. This was dispersed in HFE-458 (HCF 2 CF 2 CH 2 OCF 2 CF 2 H) and HFE-6512 (HCF 2 CF 2 CF 2 CF 2 CH 2 OCF 2 CF 2 H) respectively. A new gas collection system was designed to study volatilization in the reaction process. As a result, HFE-6512 is more suitable as the dispersion solvent than HFE-458. The suspension prepared with HFE-6512 not only has higher degradation efficiency of HD, GD, VX, 2-CEES and DMMP, but also has fewer volatile agents. Under simulated sunlight irradiation, both the surface removal and the degradation efficiency of HD, GD, VX, 2-CEES and DMMP were over 99.95% after 37 min. The results show that this suspension has potential applications in decontamination of CWAs on sensitive equipment materials. With high absorbing efficiency of CWAs and their simulants, the designed gas collection system is reliable for the selection of solvents and improvement of disinfection effect. [ABSTRACT FROM AUTHOR]

This study investigated the simultaneous abatement of atmospheric volatile organic compounds (VOCs) and persistent organic pollutants (POPs), such as polycyclic aromatic hydrocarbons (PAHs) and polybrominated diphenyl ethers (PBDEs), using an integrated technique with a bag filter (BF), photocatalysis (PC) and biotrickling filter (BTF) in an electronic waste (e-waste) dismantling workshop. Approximately 3.6 × 10 5 , 1.1 × 10 3 , and 2.5 × 10 3 ng m −3 of VOCs, PAHs, and PBDEs, respectively, were emitted from domestic stoves during a television dismantling process. During 30-day continuous treatment period, the treatment techniques eliminated 83.7%, 87.2% and 94.1% of VOCs, PAHs and PBDEs, respectively. Among three technologies, PC was responsible for the removal of 78.0% of VOCs and 72.3% of PAHs, while the BF technology removed 85.5% of PBDEs. The success assembling of different technologies depended on different gas-particle distributions of PAHs and PBDEs. Meanwhile, the decreased risk indices of all pollutants were also observed. The PC and BF treatment technologies reduced the cancer risks associated with the most VOCs and PBDEs (57.6% and 80.5%, respectively). The BF technology reduced risks from PAHs the most (86.1%), because of much higher toxic equivalency factors associated with particle-related-PAHs. After BTF treatment, the residual organic pollutants were further biodegraded and completely detoxified. This study indicated that the integrated technique, involving both excellent de-dusting and decontamination capabilities, may provide an efficient alternative to current environment purification and human health protection practices. [ABSTRACT FROM AUTHOR]

Waste foundry sand (WFS), which is a hazardous byproduct from the foundry industry, is often contaminated with potentially toxic elements (PTEs), such as Cu, Pb and Zn, and widely re-utilized as a construction material. Therefore, the depollution of WFS has been suggested due to its environment friendly reprocessing to avoid potential long-term hazardous impacts. In the current study, a unique chemically induced technique has been proposed for the removal of PTEs from WFS. EDTA, NaOH and NH 3 were used as extractants in combination or in succession. The optimum removal of PTEs was accomplished using a solid (WFS) to solution (50 mmol L −1 EDTA) ratio of 10 under strongly basic pH conditions, which was achieved with NaOH addition. The washing efficiency was further enhanced with the addition of NH 3 to the solution. The complete process cycle duration was adjusted to 9 h with a washing sequence that was repeated three times for 3 h each. The ultimate efficiencies (%) for the removal of PTEs were as follows: Cu, 98; Pb, 81; Sn, 83; and Zn, 50. The leaching of residual PTEs (%) from the decontaminated WFS was also in compliance with the regulatory levels that are defined by the monitoring authorities. [ABSTRACT FROM AUTHOR]

[Display omitted] • Construction of polymeric layered semiconductor-supported black nano-sandwiches. • Interbedded plasmonic Ag NPs in nano-sandwiches elevate solar energy conversion. • Synergistic photo-thermal catalysis for boosting decontamination efficiency. • Simultaneous eliminations of organic/antibiotic pollutants are highlighted here. Natural solar-driven synergistic photo-thermal catalytic (PTC) degradation of toxic pollutants provides promising routes for wastewater decontamination. Yet there are no satisfactory nano-catalysts that can simultaneously maximize the utilization of additional significant photo-thermal energy and the contribution of prominent photocatalytic effects. Herein, polymeric layered semiconductor-supported black nano-sandwiches are fabricated by loading dense Ag nanoparticles (NPs) on two-dimensional (2D) graphitic carbon nitride (g-C 3 N 4) and then covering with Ag 2 O nano-layers (NLs). The Ag 2 O@Ag/g-C 3 N 4 nano-sandwiches with improved broadband absorption and thermal conversion possess both enhanced photo-triggered catalytic degradation and pronounced photo-thermal utilization for boosting PTC degradation efficiency. After one-sun light irradiation of 30 min, the nano-products enable the temperature of solution to be elevated from ∼ 20℃ to ∼ 69.5℃, which is higher than that of bare g-C 3 N 4. In this way, the PTC degradation efficiency of antibiotic ciprofloxacin (CIP) solution is about 8.1 times higher than that of bare g-C 3 N 4 references. Moreover, the high-performance PTC nano-catalysts can be practically applied to the efficient degradations of organic or antibiotic mixtures in actual water samples. The present works highlight the distinctive synergistic effects of nano-sandwiches, promoting wastewater purification in the near future. [ABSTRACT FROM AUTHOR]

[Display omitted] • Fabrication methods of MOF/Substrate composites are comprehensively reviewed. • Removal performance and mechanism of contaminants in water/air are summarized. • The future perspective of MOF/Substrate composites is bright and challenging. Over these years, metal organic framework (MOF), an emerging type of hybrid inorganic–organic crystal with ultrahigh porosity and wide tunability, has showed its significant potential for environmental remediation. However, traditional MOF crystals usually appear in the powder form due to the intrinsic brittleness, insolubility, and non-thermoplastic property, greatly limiting their practical applications. In this regard, growing attentions are concentrated on incorporating MOFs into substrates to obtain various MOF/Substrate composites, which not only inherit the advantageous features of MOF crystals, but also gain hierarchical porous structures from substrates, resulting in satisfactory environmental remediation performance and operational flexibility. A comprehensive review of recent developments in MOF/Substrate composites from fabrication methods to environmental applications is provided. Over five fabrication methods of MOF/Substrate composites and their applications in water decontamination, particulate matters filtration, harmful gases removal and bacterial inactivation are discussed. Moreover, this review also summarizes the underlying mechanisms of above processes in the hope of providing some useful principles and strategies to design specific MOF/Substrate composites. Finally, the future challenges and perspectives of versatile MOF/Substrate composites in the field of environmental remediation are proposed. [ABSTRACT FROM AUTHOR]

In this study, the feasibility of implementing a pressure-driven membrane process to remove toxicity from industrial discharge waters was investigated. Several kinds of membranes from reverse osmosis (RO) to tight ultrafiltration (UF) were tested and nanofiltration (NF) was found to be the most relevant process for such a problematic. The performances of heavy metals removal by a NF membrane was thoroughly analyzed firstly for synthetic solutions and afterwards for a real effluent from French surface treatment industry. The removal performances were found to be higher than 90% irrespective of the solution investigated. Numerical simulations have shown that steric exclusions alone cannot explain such removals, and electric and dielectric contributions also contribute to separation performances. Finally, the environmental impact of a NF step was examined through two bioassays. These ecotoxicological tests have shown that metallic synthetic solutions fully lose their toxicity after NF treatment whereas industrial discharge water led to a non-negligible detrimental influence, in spite of the noteworthy rejection of metal ions. This toxicity could probably be attributed to other non-metallic pollutants. To investigate their contribution to this residual toxicity, an analysis of organic micro-pollutants (PAHs, VOCs and APs) present in the effluent has therefore been carried out before and after filtration but their amount in the permeate stream was not sufficient to explain its residual toxicity. [ABSTRACT FROM AUTHOR]

[Display omitted] • Ternary g-CN/CuFe 2 O 4 /MoS 2 exhibits excellent visible light driven photoactivity. • 98% Ciprofloxacin degradation was obtained with 0.1 g/l catalyst and 0.5 g/l PMS. • Dual Z-scheme heterojunction formation evolves efficient charge separation. • Both radical and non-radical based mechanisms were efficacious for CIP degradation. • Plausible CIP degradation pathway was proposed based on identified intermediates. Modulation in the constituent composition of heterojunction composite materials can efficiently separate photogenerated charge carriers and promote significant improvement towards visible light aided photocatalytic degradation of recalcitrant pollutants. Herein, a novel ternary heterojunction composite g-CN/CuFe 2 O 4 /MoS 2 (CNCuMo) has been fabricated by improvising g-C 3 N 4 as a fuel and the supporting matrix. The stable dual Z-scheme heterojunction manifested superior visible light driven catalytic activity through efficient electron/hole (e-/h+) separation and generation of reactive species through peroxymonosulphate (PMS) activation. Various surface bound redox cycles play prominent roles in transport of photogenerated charge carriers, activation of adsorbed PMS species and generation of reactive radicals. Benefiting from their synergistic effects, visible light aided photocatalytic degradation of refractory antibiotic Ciprofloxacin (CIP) was studied. 98% CIP was degraded (with 74.8% mineralization) using 0.1 g/l of ternary composite with 10 wt% MoS 2 (CNCuMo(10)) and 0.5 g/l of PMS, within 60 min of visible light irradiation. Scavenging experiments confirmed the simultaneous activity of both radical and non-radical species towards degradation. The system also exhibited satisfactory CIP degradation efficiency in various surface water matrixes. LCMS/MS analysis of the identified intermediates interpreted the probable degradation pathways of CIP molecules. Magnetic retrievability, recyclability for five cycles, good structural stability and low metal ion leaching tendency of the synthesized photocatalyst elucidate its potential application for degradation of emerging pollutants for water decontamination. [ABSTRACT FROM AUTHOR]

[Display omitted] • Natural ferralsol (NF), calcined ferralsol (CF500), coal slag (CS) were examined. • Calcination of NF at 500 °C enhanced its P adsorption capacity by 60.4 ± 2.2 %. • The mixture of CF500 and CS met key requirements of a potential wetland substrate. • Hybrid substrate HSSF-CWs exhibited satisfactory P removal and P effluent level. • Side effects of using CF500-CS hybrid mixed substrate were marginal. In this study, natural ferralsol (NF) was calcined to enhance its phosphorus (P) adsorption. The NF and calcined ferralsol at the selected temperature (CF500) were characterized by SEM, FTIR, XRD, XRF and other experiments to elucidate changes in morphology and physicochemical properties. CF500 and coal slag (CS) were examined as wetland media individually and combinedly. The applicability of CF500 and CS as the hybrid media in the lab–scale horizontal sub–surface flow constructed wetlands (HSSF–CWs) was evaluated. It was found that 500 °C was the best calcination temperature of NF for P adsorption. The maximum P adsorption capacity of CF500 (19.4 mg/g) was 60.4 ± 2.2 % greater than that of NF. While isotherm data of P sorption by CF500 were fitted both Langmuir and Freundlich models, the kinetic data was better described by Pseudo-second-order model. Thermodynamic parameters revealed the endothermic and spontaneous nature of the P sorption by CF500. The combination of CF500 and CS leveraged the merits of individual substrates while mitigated their demerits. The optimal mixing ratio of CF500 to CS was 1.25:1 by volume. The hybrid CF500–CS substrate HSSF–CWs demonstrated satisfactory P removal efficiency (99.44% ± 0.1) and effluent P concentration (0.08 ± 0.01 mg/L). Application of the mixed substrate in the HSSF–CWs resulted in negligible side effects on their effluent quality. Due to abundant availability of raw materials, simplicity of preparation, as well as efficiency and safety of application, a mixture of CF500 and CS is a promising hybrid substrate in HSSF–CWs for P–rich wastewater decontamination. [ABSTRACT FROM AUTHOR]

[Display omitted] • Z-scheme AgIn 5 S 8 /ZnO heterojunction exhibited superior photocatalytic activity. • Biodegradability of pharmaceutical wastewater was dramatically enhanced. • The origin of enhanced oxidation ability was unveiled. • Internal electric field drives charge separation and transfer via Z-scheme path. • Internal electric field dominated Z-scheme mechanism was proposed. Z-scheme heterojunctions are considered as prospective photocatalysts for elimination of organic pollutants. However, the origin of enhanced oxidation ability of Z-scheme heterojunctions is not well understood, and the working mechanism based on internal electrical field is still ambiguous. Here, we report Z-scheme AgIn 5 S 8 /ZnO heterojunction with superior photocatalytic activity in degrading pharmaceutical pollutants and enhancing biodegradability of pharmaceutical wastewater. The average oxidation state (AOS) and carbon oxidation state (COS) of pharmaceutical wastewater are significantly increased from 0.42 to 1.35 and 2.94 after photocatalytic treatment of AgIn 5 S 8 /ZnO. The analysis on the origin of superior photocatalytic activity reveals that the internal electric field in AgIn 5 S 8 /ZnO heterojunction works as a driving force to facilitate efficient separation of photogenerated charge carriers via Z-scheme path, thus generating spatially separated holes and electrons with high redox ability and realizing effective elimination of pharmaceutical pollutants. This study provides deep insight into photocatalytic mechanism of Z-scheme heterojunction for efficacious elimination of organic pollutants and boosted biodegradability of pharmaceutical wastewater. [ABSTRACT FROM AUTHOR]

Highlights: [•] Decontamination of drinking water networks was assessed by the Fenton’s process. [•] A detailed parametric study was done for the homogeneous process. [•] Complete degradation of pesticide was achieved in 5min, in the Fenton’s process. [•] The decontamination of deposits was assessed in a slurry batch system. [•] Pesticide chlorfenvinphos can be removed from solids by Fenton-like processes. [ABSTRACT FROM AUTHOR]

Highlights: [•] ZSM-5/EMC-2 bi-layer film on aluminum substrate. [•] Good adhesion of zeolite bottom layer on the aluminum substrate as well as between the two zeolite layers. [•] This bi-layer film is promising for technological uses in molecular decontamination. [ABSTRACT FROM AUTHOR]

[Display omitted] • Role of zirconium in fundamental and application-based research has been discussed. • Various zirconium-based adsorbents and their features have been deliberated. • Different synthesis routes of Zr-based adsorbents and their properties have also been reviewed. • Performance of zirconium sorbents for different contaminants and their regeneration capabilities have also been elaborated. Zirconium being a peculiar element, has been gaining meticulous attention in both fundamental and application-based research, which varies from industrial applications to the treatment process. Its utilization in water treatment especially in the adsorption process, has been multitudinously explored because of its distinct features. Therefore, the present study provides a comprehensive overview of different properties of zirconium and zirconium-based sorbents, their synthesis routes, performance and regeneration capabilities. Zirconium-based adsorbents have been used in a gamut of forms, each with peculiar characteristics and abilities. Their systematic designing determines their morphological, textural and chemical properties, which plays a crucial role in their performance. Different synthesis routes have been discovered for Zr-based adsorbents, enhancing their surface chemistry, functionalities and morphologies. These adsorbents are extensively explored for various inorganic pollutants decontamination via specific physical and chemical adsorption mechanism but, their application for organic pollutants has been restricted to numbers. Besides these, zirconium-based adsorbents show competent desorption-regeneration capacity that advocates its use as an adsorbent in terms of the adsorbents' cost. Therefore, these adsorbents were found to be highly effective and can be diversely modified based on the targeted pollutants. Also, their different synthesis routes, non-toxicity and reusability, make them efficient and versatile sorbent with environmental suitability, thus, can further be explored more for contaminant's removal. [ABSTRACT FROM AUTHOR]

[Display omitted] • A novel ternary LCB photocatalyst was rationally obtained using a wet chemical process. • The LCB showed an outstanding photocatalytic performance and stability for CIP degradation. • The scavenger tests as well as ESR techniques showed the role of reactive oxidative species. • Possible degradation pathways of CIP were proposed based on UPLC-MS/MS analysis. • The LCB nanocomposite holds a practical potential in the purification of real water matrix. A novel ternary symmetric double Z-scheme LaFeO 3 /g-C 3 N 4 /BiFeO 3 (LCB) heterojunction nanocomposite was rationally obtained using a wet chemical process. The ternary system was confirmed by structural analysis and surface and morphological studies. This double Z-scheme photocatalyst showed an outstanding photocatalytic performance for ciprofloxacin (CIP) degradation compared to g-C 3 N 4 , LaFeO 3 , BiFeO 3 , and their binary nanocomposites. The enhanced photocatalytic activities were primarily derived from the improved light absorption capability, effective spatial separation, and prolonged charge carriers lifetime in the double Z-scheme system. In particular, the scavenger tests and electron spin resonance spectra demonstrated that •O 2 − and •OH are the primary oxidative radical species in the photocatalytic systems and confirmed the formation of the double Z-scheme structure. The possible degradation pathways of CIP were proposed based on ultra-performance liquid chromatography tandem-mass spectrometry analysis. This study may open a new insight into the design and synthesis of highly efficient double Z-scheme photocatalyst for environmental decontamination. [ABSTRACT FROM AUTHOR]

Abstract: The contamination of soil with polychlorinated biphenyl-containing industrial fluids is a worldwide environmental problem due to their high persistence. The present study aimed to elaborate a new strategy of process integration by the joint application of biosurfactant and combined chemical–biological treatment for soil decontamination. The addition of a microbial surfactant from Pseudomonas sp. PS-17 to the combined chemical–biological treatment, utilizing liquid hydrogen peroxide or calcium peroxide and a natural consortium of microorganisms-destructors, resulted in process modification that increased the treatment efficacy of soil contaminated with polychlorinated biphenyl-containing electrical insulating oil. A 42-d combined chemical–biological treatment supplemented by biosurfactant addition resulted in an average 47–50% of polychlorinated biphenyls removal – independent of the hydrogen peroxide carrier used. Changes in the soil pH during the combined treatment application with oxidizing chemicals in moderate dosages were unsubstantial. Joint application of the biosurfactant, microorganisms and oxidizing chemicals in moderate dosages increased soil respiration and dehydrogenase activity compared to that obtained by application of the microbial consortium alone, indicating stimulation of microflora by the process integration. The application of the higher calcium peroxide doses (soil/CaO2 =1/0.005, g/g) substantially increased the soil pH and diminished soil microbial respiration compared to that for untreated incubated soil. Ethylenediaminetetraacetic acid addition in the experiments with the solid hydrogen peroxide did not affect the treatment efficacy even after the prolongation of the treatment time from 1 to 42d. Joint addition of both the biosurfactant and the chelating agent to the combined chemical–biological treatment was not effective. [Copyright &y& Elsevier]

Abstract: Soil contamination by persistent organic pollutants (POPs) is a problem faced in many countries as a result of rapid industrialisation. The suitability of Fenton oxidation for degradation of recalcitrant POPs as a short-term remediation approach has led to intense research within the field over the last few decades. In this review article, the fundamental principles and governing factors of Fenton oxidation for treating soils contaminated with POPs such as polycyclic aromatic hydrocarbons (PAHs), polychlorinated biphenyls (PCBs), polychlorinated dibenzo-p-dioxins and furans (PCDD/Fs), are firstly discussed. Current practices of soil remediation through Fenton oxidation based on studies reported in the specialised literature are then reviewed with a focus on the potential of Fenton-bioremediation and electrokinetic (EK)-Fenton treatments in conjunction with in situ applications. An exhaustive bibliography on column studies is also covered in this work with emphasis on the technical approaches used. Finally, the last section of the article is focused on assisting soil scientists and environmental professionals in implementing in situ Fenton oxidation (ISFO) and provides some insights into future development of ISFO. [Copyright &y& Elsevier]

Abstract: This study aimed at investigating the reactivity of aniline-based pharmaceuticals with sulfate radical anion generated by the peroxymonosulfate (PMS)/Cobalt(II) system and by taking sulfamethoxazole and diclofenac as probe compounds. Transformation pathways were proposed for both pharmaceuticals relying on the identification of the main reaction intermediate products using liquid chromatography coupled to time of flight mass spectrometry. For diclofenac, the major transformation pathway led to the formation of a quinone imine derivative while for sulfamethoxazole a nitro derivative was obtained as the major intermediate. However, in both cases, oxidative reactions started with the formation of a N-centered radical probably through an one-electron transfer from the pharmaceutical to sulfate radical anion. This was followed by further multistep degradation involving decarboxylation, hydroxylation and bond cleavage reactions in route to mineralization. From a kinetic point of view, aniline-based pharmaceuticals quickly reacted with sulfate radical anion with second order kinetic rate constants in the 9–10×109 M−1 s−1 range. Sulfate radical-based technologies show promising results for the removal of these particular pharmaceuticals from wastewater treatment plant effluents mainly because of the higher selectivity of sulfate radical anion over hydroxyl radical, limiting radical scavenging by natural organic matter and allowing for higher abatement and mineralization rates. [Copyright &y& Elsevier]

Abstract: This work evaluates the technical feasibility of large-scale combined solar photo-Fenton/aerobic biological treatment targeting the treatment of a real industrial wastewater polluted with commercial pesticides. Photo-Fenton experiments were carried out under sunlight in a CPC-based plant (150m2 of solar collectors and the total photo-reactor volume 1060L). The biological reactor was an immobilized biomass reactor (IBR, 2× 1230L) filled with Pall®Ring supports colonized by activated sludge from a municipal wastewater treatment plant. The first study performed was focused on the decontamination of wastewater containing a selected mixture of five commercial pesticides (Vydate®, Metomur®, Couraze®, Ditimur-40® and Scala®) at 500mg/L of initial dissolved organic carbon (DOC). Real wastewater containing pesticides was tested at two different initial DOCs (200 and 500mg/L). The solar photo-Fenton was always performed in batch mode at pH adjusted to 2.8 and with 20mg/L of Fe2+, while the biological reactor was operated both in batch and continuous mode. Mineralization was followed by measuring DOC and chemical oxygen demand (COD) and the composition of the real wastewater was determined by liquid chromatography electrospray time-of-flight mass spectrometry (LC-TOF-MS). It has been demonstrated that photo-Fenton is able to enhance biodegradability of real wastewaters containing biorecalcitrant compounds at concentrations up to 500mg/L but it has been also pointed out that the process should be optimized by a proper selection of treatment time and H2O2 dose. [Copyright &y& Elsevier]

Abstract: In this study, the capacity of decontaminated polluted soils, by using the sequence washing with cyclodextrin-electrochemical treatment was evaluated. The initial step of the process involved contacting polluted soil with cyclodextrin to enhance recovery of phenanthrene from soil. The total phenanthrene removal in a washing column with aqueous solutions of 1% hydroxypropyl-β-cyclodextrin attained a value of almost 70% after 6 days. The second step of this operational strategy concerned regeneration of the washing solution via electrochemical phenanthrene degradation. The phenanthrene was almost totally degraded in 1 day and the extracting ability of this treated solution was confirmed. By application of this combined technology, it is possible to recycle the washing solution reducing the consumption of cyclodextrin solutions. Consequently, it has provided an effective and economic treatment of PAHs polluted soil. [Copyright &y& Elsevier]

[Display omitted] • The property, category, synthesis, characterization and application of LDH-based catalysts are summarized. • Activation and mechanism of LDH-based catalysts in three kinds of AOPs are discussed. • LDH-based catalysts show superior catalytic performance for various refractory organics removal. • The prospects and challenges of LDH-based catalysts are proposed. Layered double hydroxides (LDHs) are a class of anionic clays with flexible tunability, facile exchangeability of intercalated anions, good thermal stability, and plentiful active sites. By virtue of their advantages, LDHs, as catalysts, catalyst precursors or catalyst supports, have been widely used in advanced oxidation processes (AOPs) to degrade organic pollutants in water and showed prominent catalytic performance as concluded from nearly 100% removal of contaminants in a relatively short time. To shed light on the synthesis, application and catalytic performance of LDH-based catalysts, this review summarized the properties, categories, synthesis and characterization methods of LDH-based catalysts, and their applications, reaction mechanisms and the corresponding influencing factors in heterogeneous Fenton-like processes, sulfate radical based AOPs and photocatalysis. Compared with LDHs, LDOs and nanocomposites possess other performances that are beneficial for AOPs catalytic processes, such as good dispersity, easy separability and synergistic effect. Moreover, the optimum material design and corresponding reaction mechanisms would be varied with the types of AOPs. In the end, based on the current challenges in LDH-based catalysts, future researches are suggested to focus on developing green and efficient synthetic method, optimizing material design, and promoting their practical application. [ABSTRACT FROM AUTHOR]

[Display omitted] • Advanced oxidation processes (AOPs) effectively remove organics from produced water. • Both homogeneous and heterogeneous processes are reviewed and evaluated. • Photo-assisted techniques and electrochemistry increase the efficiency of oxidation. • AOPs are flexible in terms of configuration and combination with other treatment steps. • The most effective processes need important development for real-scale implementation. Produced water is the main by-product generated by fossil fuel extraction activities. This wastewater is often heavily contaminated and associated with significant health, safety, and environmental risks; thus, adequate treatment systems are required to bring these streams to a quality that may be suitable for their recycling, reuse, or discharge into the environment. Advanced oxidation processes (AOPs) are increasingly studied to purify produced waters, and specifically for the removal of organic pollutants in the aqueous and non-aqueous phases. This review evaluates Fenton-based oxidation, heterogeneous catalysis, electro-oxidation, photo-assisted processes, and homogeneous advanced oxidation processes to remove organic contaminants in produced water. The efficiency and applicability of the reviewed approaches are discussed with particular attention to the configurations within the water purification train. Ozonation, Fenton-based techniques, heterogeneous photocatalysis, and anodic oxidation techniques are the most widely researched AOPs in produced water treatment. Photo-assisted processes and electrochemistry have been shown to significantly improve the effectiveness of decontamination of more traditional processes. Oxidation can be exploited as polishing stage of already pre-treated effluents with the final goal of reuse with closing of the water cycle, or as a primary/secondary treatment step to facilitate subsequent biological processes and membrane separation steps. The combination of two oxidation approaches or the oxidation with a membrane-based treatment within the same hybrid system is particularly promising. Challenges, research needs, and future perspectives are thus examined to guide efforts aimed at improving the application of advanced oxidation in produced water treatment and accelerate its implementation at real scale. [ABSTRACT FROM AUTHOR]

• Fluoride removal from natural groundwater (4–10 mg L−1 F -) by electrocoagulation. • Electrodes of Al and Al Alloys permit compliance with the WHO guideline, <1.5 mg L−1. • The coexisting ion interferences do not impede the removal of fluoride in the flocs. • F− removal improves with current density in continuous flow electrocoagulation reactors. • Electrocoagulation plants, easy to install, allow water treatment price ~0.33 USD m−3. This review addresses the removal of fluoride contained in different natural groundwater samples from various parts of the world using the electrocoagulation (EC) process. A detailed analysis of different metals (Fe, Al) and Al alloys used as sacrificial electrodes is carried out. The best performance in removing high concentrations of fluoride from natural groundwater (2–10 mg L−1), until fulfilling the World Health Organization (WHO) recommendation (<1.5 mg L−1), is obtained using aluminum and aluminum alloys. The fluoride removal occurs through the substitution of a fluoride ion by a hydroxyl group from aluminum flocs, highlighting that the presence of coexisting ions such as hydrated silica, sulfates, phosphates, bicarbonates, magnesium, calcium, and so on, do not impede the fluoride removal. On the other hand, the modest removal of fluoride with iron impedes satisfy the WHO guideline. Total operating costs for the removal of fluoride with Al electrodes are between 0.38 and 0.62 USD m−3. Among the different continuous EC reactors, those with parallel plates stand out, because they allow control the flow rate and the wear of the electrodes is uniform, in addition to being relatively easy to scale-up. The importance of mathematical modeling and the use of computational fluid dynamics (CFD) simulations to understand the EC process and design smart reactors is also analyzed. Finally, an in-depth analysis of EC's scientific challenges in the treatment of groundwater contaminated with fluoride is presented. [ABSTRACT FROM AUTHOR]

• The application of SR-AOPs for IWW treatment was systematically reviewed. • The theoretical (reactive species) and practical aspects (IWW composition) were analyzed. • SR-AOPs are vastly studied in landfill leachate and petrochemical IWW effluents. • Its advantages include the simultaneous HO/SO 4 − generation with non-radical pathways. • Limitations include the difficulty to apply heating, microwave and ultrasound activation. Over the last years, Sulfate Radical-based Advanced Oxidation Processes (SR-AOPs) have received considerable attention due to their high versatility and efficacy in disinfection and decontamination. Their advantages over classical AOPs, the generation of sulfate radicals ( S O 4 ∙ - ) from peroxydisulfate (PDS, S 2 O 8 2 - ), or joint sulfate and hydroxyl radicals ( H O ∙) production from peroxymonosulfate (PMS, H S O 5 -) and their abundant activation methods have facilitated their introduction into various remediation and effluent decontamination processes. In this review, we present the advances in the field of industrial wastewater (IWW) treatment by SR-AOPs, by activation of either PMS or PDS via any suitable method, in homogeneous or heterogeneous (photo)catalytic processes. This review aims to present the state of the art in SR-AOPs application for IWW treatment, and act as a guideline of the field advances, summarize the previous application experiences, hence avoid research pitfalls and empower better IWW treatment practices. After an integrated presentation of the dominant pathways towards IWW decontamination, we discuss the SR-AOPs application in the treatment of effluents such as landfill leachate, petrochemical and pharmaceutical WW, pulp or paper industry effluents, textile and winery WW, as well as less studied processes such as coking, olive mill or soil washing effluents. Finally, the advantages and shortcomings of SR-AOPs for IWW treatment, as well as their perspectives are discussed. [ABSTRACT FROM AUTHOR]

• Simultaneous coupling of photocatalysis and biotransformation in water was reviewed. • Synergistic performance was summarized for oxidation and reduction of pollutants. • Key factors affecting decontamination performance in coupled processes were analyzed. • Interaction mechanisms between photocatalysts and microorganisms were elucidated. Decontamination of water polluted with recalcitrant chemicals, such as phenolic and aromatic substances, for which conventional wastewater treatment processes are largely not effective, remains a major challenge all over the world. The simultaneous combination of photocatalytic and biological processes in a single system, either with or without the support of porous carriers, exhibits superior synergistic performance for removing refractory contaminants with the advantages of both photocatalysis and biotransformation. This promising emerging alternative, defined as simultaneous coupling here, has attracted increased attention and has been substantially developed over the last five years. To our best knowledge, this is the first critical review systematically focusing on the simultaneous coupling of photocatalytic and biological processes in enhancing decontamination of recalcitrants from water. The current review includes not only the synergy for pollutant oxidation/reduction removal and corresponding key factors affecting coupled systems, but also the underlying mechanisms of two different couplings in the interaction view of photocatalytic and biological responses. Last but not least, the challenges and opportunities faced by the coupling are pointed out. This review can provide useful information on the design and application of the synergistic coupling of chemical and biological processes for efficient and complete decontamination of recalcitrant compounds in water. [ABSTRACT FROM AUTHOR]

• Cellulose nanostructures (CNS) were phosphorylated and improved the Cu adsorption. • Biodegradable membranes of PBAT were prepared via inversion phase technique. • The CNS improved the mechanical properties of PBAT membranes. • Membranes with phosphorylated CNS showed better chrome removal from water samples. • The developed system shows potential for future applications in water treatment systems. The removal of chromium from contaminated water was investigated using biodegradable membranes and functionalized cellulose nanoparticles. We used poly(butylene adipate-co-terephthalate), a flexible polymer, for membrane development via phase inversion technique. CNS, with and without phosphorylation (CNS-P), was used aiming to improve the removal of chromium from contaminated drinking water. The neat CNS showed limited efficiency on the Cr removal. On the other hand, CNS-P indicated removal of 93% and 88% of Cr(VI) and Cr(III), respectively. The Cr removal can be associated with CNS higher surface area and active sites, which allows more regions for immobilization of chromium species. Also, at lower pH the CNS-P presents a surface charge that can interact via electrostatic forces with the chromium species, which increases the removal efficiency. CNS-P also showed greater thermal stability due to phosphorylation. The addition of CNS and CNS-P improved the membranes' mechanical performance, which improves the applicability of this material, with potential application in domestic houses and water treatment stations. A small device for domestic use was tested to confirm the efficiency of the membranes, and the functionalized membranes showed 71% of chromium removal, which highlights its potential for water decontamination. [ABSTRACT FROM AUTHOR]

• Strongly coupled AgBiO 3 based recyclable and reusable composite membranes with no significant leaching of Ag ions. • Enhanced water flux and protein fouling resistance with FRR 87 ± 5% and BSA as model foulant. • Complete E. coli remediation in the presence of light as well as dark conditions. • Effective bactericidal action against secondary wastewater verified by live/dead assay. • More than 83% degradation of recalcitrant Methylene Blue and 4-Nitrophenol. Due to the limited access to safe drinking water, there is an emerging need to have a quick water decontamination strategy wherein all the major contaminants of water like dyes, organic compounds, and pathogenic bacteria can be removed using a sustainable approach. Herein, we introduce a facile method to strongly couple photocatalytic dual active AgBiO 3 (AB) (light and dark active) onto a membrane consisting of Polyvinylidene fluoride (PVDF) and Poly (butylene succinate-co-adipate) (PBSA). Due to this strong coupling, the integrity of the catalyst was retained, and no significant leaching of Ag ions from the composite membranes was observed. The bactericidal response of this composite membrane was assessed in the presence of light and dark using E. coli as the model bacterium. Also, the efficacy of this strategy was extended to decontaminate secondary treated wastewater. It was also observed that the photocatalytic activity of the composite membrane was durable and highly effective in degrading recalcitrant pollutants like methylene blue and 4-nitrophenol, which are considered here as models recalcitrants. This facile strategy, besides improving the flux, enhanced the protein fouling resistance against Bovine serum albumin (BSA) and rendered robust bactericidal action. Taken together, these membranes can be further explored for sustainable water remediation strategies. [ABSTRACT FROM AUTHOR]

• A Cu@CuO/CG-aero Janus membrane is designed for water decontamination. • The as-prepared Janus membrane possesses low thermal conductivity and high thermal diffusivity. • An efficiency of ~88% is achieved for optothermal conversion under 1 sun irradiation. • The pollutants (e.g., organic dyes, heavy metal ions, and pathogens) are almost entirely eliminated after purification. Today, people face a global challenge of clean water shortage due to a combination of freshwater scarcity and huge sewage discharge. To preserve human sustainability, it is urgent to develop facile and inexpensive routes for the conversion of wastewater into clean water. In this work, we demonstrate a straightforward method with a solar-powered Cu@CuO/CG-aero Janus membrane. The desired optical and thermal features of the Janus membrane allow it to efficiently evaporate water under 1 sun irradiation (88% energy conversion efficiency). More importantly, the as-prepared Janus membrane can be employed for the efficient decontaminations of sewage, involving organic dyes, heavy metal ions, and pathogens (bacteria, viruses, parasites). In contrast to the traditional and complex wastewater treatment techniques, this solar-powered Janus membrane reveals many advantages (e.g., high performance, facile, handy, and low-cost) for water decontamination, which can be potentially spot-used to obtain clean water in backward areas. [ABSTRACT FROM AUTHOR]

• Three different plasma regimes were evaluated for PFOA degradation. • Self-pulsing discharge (SPD) performed better in terms of G 50 value. • Effect of liquid media and plasma feed gas on degradation efficiency were discussed. • Conductivity greatly affected input power and thus influenced G 50 value of SPD reactor. The development of efficient plasma-based technologies for water treatment in general and decontamination from perfluoroalkyl substances, in particular, is a timely and challenging research topic. This study investigated the degradation of PFOA (perfluorooctanoic acid) in water using three reactors with different configurations and implementing different plasma regimes. Two reactors were available from previous studies on other recalcitrant pollutants and use, respectively, corona discharge and plasma in gas bubbles. The third reactor was designed and developed for this specific application and uses a self-pulsing streamer discharge (SPD) over the liquid surface. The performance of the three reactors was assessed and compared using air as plasma feed gas and a PFOA solution (41.4 mg/L) in Milli-Q-water. The SPD reactor was found to be the most efficient in terms of energy efficiency and PFOA conversion and degradation rate. It was therefore further tested and characterized by studying the effects of changing the aqueous media in which PFOA was dissolved (Milli-Q and tap water) and the plasma feed gas (synthetic air, ambient air and argon). Due to the formation of nitrous and nitric acids, especially for plasma generated in ambient and synthetic air, the solution pH, conductivity, and hence the plasma input power changed significantly during the experiments. The best results were obtained using argon for plasma inception and PFOA solutions in tap water: the energy efficiency and fluoride recovery were 561 mg/kWh and 47%, respectively. [ABSTRACT FROM AUTHOR]

• Successful preparation of colored composite of TiO 2 to embed on fabric. • Complete degradation of formaldehyde in water and air under light irradiation. • Colored photocatalytic fabrics deactivate bacteria with high efficiency. • OH is the major species in this photocatalytic system. This paper presents the fabrication of colored photocatalytic fibers by individually combining white TiO 2 with red α-Fe 2 O 3 , green copper perchlorophthalocyanine (CuPcCl 16), and blue copper phthalocyanine (CuPc), followed by immobilization of three as-prepared nanocomposites (i.e., Fe 2 O 3 /TiO 2 , CuPcCl 16 /TiO 2 , and CuPc/TiO 2) onto the low melting point sheath-core composite polyester fibers (LMPET). The spectroscopic and surface measurements of colored fabrics show uniform distribution of the composites on LMPET fibers. Compared with TiO 2 -based white fabric, the prepared colored catalytic fabrics have better performance in photocatalytic degradation of formaldehyde (HCHO), a pollutant in water and indoor air. In addition, the prepared fibers could be recycled or reused without any appreciable decrease in their effectiveness. The investigation of antibacterial activity of colored fabrics shows 6-log inactivation of both Escherichia coli and Staphylococcus aureus. The enhancement in the photocatalytic activity of colored fabric is attributed to a broadening photo-absorption region and also a decrease in the recombination of electron-hole pairs. In the photocatalytic process, an increase in photocurrent response suggests the increase in charge separation. Additionally, hydroxyl radicals (OH) as the major reactive species in photocatalytic activity of colored fabrics are confirmed by the electron paramagnetic resonance technique. This study suggests that the developed colored photocatalysts can be applied in textiles to clean water and air. [ABSTRACT FROM AUTHOR]