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Аbstract: With the rapid growth of industrialization/urbanization, the discharge of industrial effluent into the environment is increasing day by day. Conventional technologies for wastewater treatment possess difficulties in meeting all the requirements of wastewater discharge standards, and therefore, the exploration and establishment of new procedures to treat wastewater is a need of hour. Advanced oxidation processes (AOPs) possess an ability of strong oxidation, complete destruction and mineralisation, and no secondary pollutants. It has been proved in the literature that the addition of the catalyst in AOPs can largely enhance the treatment efficiency. The current study mainly emphasizes the practical applications of AOPS towards textile wastewater treatment. The study includes the pros and cons of individual AOPs, fixed photocatalysis, the dual process of photocatalysis and photo-Fenton coupled photocatalysis/photo-Fenton and biological treatment process. This article summarizes the useful theoretical foundation of the scientists and discusses the key areas that need more investigation in the fields of AOPs for industrial wastewater treatment. [ABSTRACT FROM AUTHOR]

The decomposition of gaseous toluene as a representative volatile organic compound using 200 kHz ultrasonic waves was investigated as a new air cleaning method that does not require an ultraviolet light source, in accordance with the Minamata Convention on Mercury. Upon applying ultrasonic irradiation to water in a batch reactor, the removal ratio of gaseous toluene above the water reached 91.0% at 10 ppm and 92.7% at 40 ppm. The addition of t-BuOH, a radical scavenger that suppresses ultrasonic decomposition, inhibited the removal of gaseous toluene, indicating that the ultrasonic irradiation not only accelerated the dissolution of toluene into the water but also mediated its decomposition. Further experiments in a flow system revealed that the removal ratio of gaseous toluene decreased with increasing toluene flow rate, whereas the total mass of toluene removed increased, suggesting that sufficient amounts of the active species, such as •OH radicals, required for the initial decomposition of toluene were formed in the liquid phase upon ultrasonic irradiation. [ABSTRACT FROM AUTHOR]

The efficient degradation of organic pollutants in diverse environmental matrices can be achieved through the synergistic application of piezo‐catalysis and photocatalysis. The focus of this study is on understanding the fundamental principles and mechanisms that govern the collaborative action of piezoelectric and photocatalytic materials. Piezoelectric nanomaterials, under mechanical stress, generate piezo‐potential, which, when coupled with photocatalysts, enhances the generation and separation of charge carriers. The resulting cascade of redox reactions promotes the degradation of a wide spectrum of organic pollutants. The comprehensive investigation involves a variety of experimental techniques, including advanced spectroscopy and microscopy, to elucidate the intricate interplay between mechanical and photoinduced processes. The influence of key parameters, such as material composition, morphology, and external stimuli on the catalytic performance, is systematically explored. This study contributes to the increasing knowledge of environmental remediation and lays the foundation for the development of advanced technologies using piezo and photocatalysis for sustainable pollutant removal. [ABSTRACT FROM AUTHOR]

The global population and economic development surge has substantially increased water demand, resulting in heightened sewage and pollutant generation, posing environmental hazards. Addressing this challenge necessitates the implementation of efficient and cost-effective water reclamation methods. Non-thermal plasma technology (NTP) has emerged as a promising solution, garnering attention for its superior efficiency compared to alternatives. While existing studies have predominantly focused on energy efficiency and pollutant removal, limited research has delved into the biological removal aspect, particularly concerning algae. This study utilized a dielectric barrier plasma diffuser to eliminate Spirulina microalgae (Spirulina platensis) from wastewater solutions, demonstrating higher algae removal and superior mass transfer compared to alternative plasma methods. The effect of sample volume, input voltage and power, flow rate, and initial solution concentration on the algae removal was investigated. Investigation of operational parameters revealed the best condition resulting in a 98 % removal rate and 20 g/kWh energy efficiency. The best conditions for the removal of Spirulina microalgae were considered in a sample volume of 50 mL, a voltage of 7.6 kV, a flow rate of 700 mL/min, and an initial solution concentration of 1280 mg/liter. Scanning Electron Microscope (SEM) images illustrated the impact of active species on cell structure, leading to the destruction of spiral form and loss of reproductive ability. The study underscores the potential of NTP for efficient algae removal and identifies key active species involved in the process. The removal of Spirulina microalgae was attributed to a combination of singlet oxygen (1O2), hydroxyl radicals, and ozone.

To address the problem of petrochemical organic pollutants in water, specifically monoethylene glycol (MEG) present in industrial process streams, in this research, we synthesized and evaluated a multifunctional nanocomposite, Fe3O4@MC/MWCNT-CuO/Ag. The nanocomposite was produced by combining magnetic Fe3O4 nanoparticles, methylcellulose (MC), multi-walled carbon nanotubes (MWCNTs), and CuO/Ag nanoparticles by an integrated synthesis process. A consistent dispersion of nanoparticles, with diameters ranging from 30-40 nm, was discovered by FESEM analysis, showing effective integration without aggregation. Effective synthesis was demonstrated by well-doped and evenly dispersed CuO and Ag nanoparticles. Functional groups that improve electrostatic interactions with contaminants hence enhancing catalytic performance and adsorption efficiency, were validated by FTIR analysis. XRD indicated an unchanged crystal structure with an average crystallite size of 8.67 nm. The anticipated elemental composition was verified by EDS & mapping. A VSM study revealed magnetic characteristics (9.33 emu/g) that simplify nanocomposite separation and reuse. TGA proved thermal stability to be up to 600 °C. A BET study showed a highly specific surface area of 67.661 m2/g, enhancing adsorption. According to DRS and PL studies, the bandgap was lowered by 1.31 eV, which led to better optical absorption. The nanocomposite exhibited notable MEG removal efficiency, with 72 % in adsorption, 65 % in photocatalysis, and 56 % in sonocatalysis. This makes it a promising alternative for the remediation of organic pollutants in water treatment.

The research aims to develop an advanced electrooxidation process for decolorization of recalcitrant dye. To enhance the radical formation, a combination of UV irradiation and electrooxidation (UV/EO) is used. Methylene Blue (MB), Rhodamine B (RB) and Congo Red (CR) dyes were used as model compounds to represent recalcitrant dyes. The performance of UV/EO process was investigated under various operating factors (i.e., current density (CD), voltage, pH, NaCl, anodic material), and compared with chlorination, UV irradiation, and electrooxidation (EO) process. MB was the highest resistant dye to the UV/EO process. The UV/EO process exhibited a synergistic effect on decolorization, and it removed MB 1.35 time faster than the EO process. Based on indirect determination of •OH, the •OH formation in the EO process was 2.4 ×10−13 M, which lower than that in the UV/EO process by 4 times. The second-order rate constant for MB oxidation by HO• (kHO•,MB) was 3.31 × 109 M−1s−1. The pseudo 1st-order decolorization kinetic (k’) was independent with voltages, but directly depended on CD and NaCl concentrations. Lower pH enhanced the k’ value. The specific energy consumption was in a range of 0.408 – 5.303 kWh/m3, depending on the k’ value. The energy consumption decreased with higher the k’ value, except for increasing CD. The Boron Doped Diamond (BDD) was more effective in the decolorization rate than dimensional active anode (DSA) by 1.6 times. Treatment of industrial dye wastewater by the UV/EO process eliminated color intensity (ADMI), COD, and BOD5 by 80 %, 91 %, and 9 %, respectively.

Abstract Nanomaterials have been extensively employed in various applications over the past several decades, however, the stability of functional nanoparticle catalysts (NPCs) for effective degradation of organic contaminants remains a significant challenge. Herein, we present a cost-effective biochar loaded uniformly dispersed ultra-stable Co nanoparticles with an average diameter of 8 nm as a highly efficient peroxymonosulfate (PMS) activation catalyst. The reactive radicals produced from the catalyst/PMS system are able to degrade several model organic pollutants of environmental and public health concerns, including trichlorobiphenyl, bisphenol A and diethyl phthalate, with less pH limitation and Co2+ leaching. Mechanism investigation demonstrates that the CoN plays the key role in the catalyst stability and PMS activation via acid resistance and electron bridging effects, respectively. Meanwhile, the incorporation of nitrogen (N) and sulfur (S) atoms within the substrate is considered to bolster the adhesion strength between metal nanoparticles and the carbon matrix via strong metal-support interaction. The catalyst was further applied in practical treatment of water and soil polluted by organic pollutants, exhibiting a satisfactory degradation efficiency (> 90% in 60 min) for environmental applications.

A catalyst based on zero-valent iron nanoparticles (nZVI) supported by zeolite Y (zeolite Y-nZVI) was synthesized to improve the performance of the heterogeneous electro-Fenton-like process for treating a toxic pesticide wastewater with pH of 6. Central Composite Design (CCD) under Response Surface Methodology (RSM) was applied to design the experiments and find the optimal parameters including time, current intensity, hydrogen peroxide volume (or concentration) and the synthesized catalyst dosage. The results showed that the chemical oxygen demand (COD) removal under the optimal conditions (time of 125 min, current intensity of 272 mA, hydrogen peroxide volume (or concentration) of 0.19 ml (8.102 × 10−3 M), and zeolite Y-nZVI catalyst dosage of 1.78 g) was at 83.69 % for treating a wastewater with pH of 6 although this increased to 91.26 % at pH of 3 under the Fenton reactions. In fact, the synthesized catalyst could properly treat wastewater in a pH close to neutral one. Since electro-Fenton is as efficient technique for treating the hazardous pollutants such as pesticide, it can successfully be used by their manufacturing factories. Since it properly works in the acidic pHs, it is not as applied technique for most of industries. Therefore, catalytic electro-Fenton process can be performed in (or near) a neutral pH. Since electro-Fenton is basically associated with iron, a catalyst based on it (such as Fe°) was chosen and supported on an abundant and suitable material such as zeolite. The synthesized catalyst was initially synthesized and characterized, and then successfully applied in the electro-Fenton process to treat a real pesticide containing wastewater obtained from industry.

The increase in pork consumption and its reputation as one of the best sources of protein has led to growth in this industry, however, its production generates a significant amount of swine wastewater (SWW). Conventional biological treatment methods are typically used to treat SWW. However, their applicability in small and medium sized enterprises (SMEs) in the swine industry is limited due to their high space requirements. Therefore, advanced oxidation processes (AOPs) such as photofenton (PF) and electrocoagulation (EC) represent a potential alternative for SWW treatment due to their lower space requirements. The aim of this study was to treat SWW by integrating the PF process followed by EC as a technological couple to optimize the removal efficiency of pollutants present in SWW. Experiments were conducted in a 2 L batch reactor, examining the effects of hydrogen peroxide (H2O2) concentration (0.5, 2.5, 5.0 g L−1) and current density (10, 50, 90 A m−2) on pH, organic matter, nutrients, and germination index (GI). The results showed that the optimum process conditions correspond to 2.6 g L−1 H2O2 and a current density of 41 A m−2. Under these conditions, an effluent is obtained with pH values of 7.8, TSS of 385 mg L−1, COD of 254 mg L−1, BOD5 of 139.8 mg L−1, TN of 190.4 mg L−1 and GI of 117 %. The results showed that the effluent complies with the Colombian standards. From a cost perspective, the use of Photo-Fenton to treat wastewater under these conditions would be US$ 0.7 per liter.

AbstractA low-cost sol-gel method is used to synthesize C-doped TiO2 (C–TiO2) nanoparticles. Nanoparticles of undoped TiO2 and varying C weight percentages (4%, 6%, and 8%) of C–TiO2 are generated. XRD, FTIR, FESEM-EDS, UV–Vis DRS, PL, BET, and XPS are used to analyze the characteristics of all the nanoparticles. The EDS data indicate that the TiO2 lattice has been successfully doped with carbon. The band-gap energy of 6% C–TiO2 is shifted to 2.94 eV, as confirmed by UV–Vis DRS, resulting in improved visible-light absorption and, hence, increased photocatalytic activity by lowering the electron-hole recombination rate. Under natural sunlight irradiation, 6% C–TiO2 achieves a 91% removal efficiency of Rhodamine B (RhB) dye in 90 min and 84% removal efficiency of Congo Red (CR) dye in 30 min. A probable photodegradation pathway was estimated using the scavenger test, and the •O2− and •OH radicals are recognized as potentially active species for RhB degradation. [ABSTRACT FROM AUTHOR]

Growing attention has been paid to the rational treatment of antibiotics‐bearing medical wastewater. However, the complexity of polluted wastewater makes the later comprehensive treatment difficult only by the Advanced Oxidation Process technique. Therefore, the coupled water treatment techniques including contaminant mineralization and regeneration of cleanwater become very attractive. A bimetallic functional hollow nanoreactor defined as (Co@SiO2/Cu−X) was successfully constructed by coating a Cu‐doped silica layer on the metal‐organic framework (ZIF‐67) followed by programmed calcination in nitrogen. The nanoreactor was endowed with a hollow configuration composed of mesoporous N‐doping C‐Silica hybrid shell encapsulated ultrafine Cu and Co metallic species. Such a configuration allows for the efficient diffusion and open reaction space of big contaminant molecules. The catalytic synergy of exposed Co−Cu bimetals and the easy accessibility of electron‐rich contaminants by polar N doping sites triggered surface affinity make the optimal Co@SiO2/Cu‐6 afford an excellent catalytic norfloxacin mineralization activity (7 min, kabs=0.744 min−1) compared to Cu‐free Co@SiO2‐6 (kabs=0.493 min−1) and Co‐6 (kabs=0.378 min−1) Benefiting from the above unique advantages, Co@SiO2/Cu‐6 show excellent removal performance in degrading different pollutants (carbamazepine, oxytetracycline, tetracycline, and bisphenol A) and persistent recycled stability in removing NFX. In addition, by virtue of the excellent photothermal properties, interfacial solar water evaporation application by Co@SiO2/Cu‐6 was further explored to reach the regeneration of cleanwater (1.595 kg m−2 h−1, 97.51 %). The integration of pollutant mineralization and solar water evaporation by creating the monolith evaporation by anchoring the Co@SiO2/Cu‐6 onto the tailored melamine sponge allows the regeneration of cleanwater (1.6 kg⋅m−2⋅h−1) and synchronous pollutant removal (NFX, 95 %, 60 min), which provides potential possibility the treatment of complicated wastewater. [ABSTRACT FROM AUTHOR]

Soil contamination by polycyclic aromatic hydrocarbons (PAHs) has been an environmental issue worldwide, which aggravates the ecological risks faced by animals, plants, and humans. In this work, the composites of nanoscale zero-valent iron supported on carbonylated activated carbon (nZVI-CAC) were prepared and applied to activate persulfate (PS) for the degradation of PAHs in contaminated soil. The prepared nZVI-CAC catalyst was characterized by scanning electron microscopy (SEM), X-ray diffractometer (XRD), Fourier transform infrared spectroscopy (FTIR), and X-ray photoelectron spectroscopy (XPS). It was found that the PS/nZVI-CAC system was superior for phenanthrene (PHE) oxidation than other processes using different oxidants (PS/nZVI-CAC > PMS/nZVI-CAC > H2O2/nZVI-CAC) and it was also efficient for the degradation of other six PAHs with different structures and molar weights. Under optimal conditions, the lowest and highest degradation efficiencies for the selected PAHs were 60.8% and 90.7%, respectively. Active SO4−• and HO• were found to be generated on the surface of the catalysts, and SO4−• was dominant for PHE oxidation through quenching experiments. The results demonstrated that the heterogeneous process using activated PS with nZVI-CAC was effective for PAH degradation, which could provide a theoretical basis for the remediation of PAH-polluted soil. [ABSTRACT FROM AUTHOR]

Because of its high toxicity and severe degradation, phenol has caused serious environmental pollution, and it is urgent to explore a stable and efficient degradation method of phenol. In this study, Ni/Fe bimetallic atomic cluster composite catalyst activated peroxymonosulfate (PMS) to degrade phenol efficiently. The experimental results show that the phenol degradation rate can reach 100% in a wide range of pH (3–11), and the system offers good stability in repeated experiments. The free radical quenching investigation and electrochemical characterization showed that the non-free radical pathway dominated the degradation system, and a large amount of singlet oxygen and rapid electron transfer promoted the efficient degradation of phenol in wastewater. This study opens up a new way for bimetallic atom cluster catalysts to activate PMS to degrade organic pollutants. [ABSTRACT FROM AUTHOR]

BACKGROUND: The efficient and green technology of dye removal has been widely investigated. In this study, a bio‐electro‐Fenton system was used to degrade methyl orange (MO). For the system optimization, five experimental groups were detected, including pH (1–6), iron (Fe2+) concentration (3–15 mmol L−1), airflow rate (0–20 mL min−1), external voltages (0.2–1.0 V) and initial MO concentration (20–100 mg L−1). RESULTS: Optimal conditions of pH 3, Fe2+ concentration 9 mmol L−1, air flowrate 12 mL min−1, external voltage of 0.6 V and MO concentration 60 mg L−1 were selected, resulting in a 92% efficiency. For the pathway investigation of MO degradation, under oxidization by ˙OH, demethylation, broken azo bonds and broken benzene ring structure were obtained. Intermediate products were predicted. For the system evaluation, energy consumption of 0.15–0.59 KWh was determined for 1 m3 MO wastewater. The total cost of degrading MO wastewater could decrease to US$470.0 m−3 by adjusting operational time. CONCLUSION: Considering the Fe2+ regeneration and the low energy consumption, this bio‐electro‐Fenton system can be considered as one of the most environmentally‐friendly approaches for MO degradation; however, quantitative evaluation on sustainability needs to be further discussed via advanced assessment tools (such as life‐cycle assessment). © 2024 Society of Chemical Industry (SCI). [ABSTRACT FROM AUTHOR]

Contamination of groundwater with fluoride represents a significant global issue, with high concentrations posing serious public health threats. While fluoride is a critical element in water, excessive levels can be detrimental to human health and potentially life-threatening. Addressing the challenge of removing fluoride from underground water sources via nanotechnological approaches is a pressing concern in environmental science. To collate relevant information, extensive literature searches were conducted across multiple databases, including Google Scholar, PubMed, Scopus, Web of Science, the American Chemical Society, Elsevier, Springer, and the Royal Society of Chemistry. VOS Viewer software version 1.6.20 was employed for a systematic review. This article delivers an exhaustive evaluation of various groundwater fluoride removal techniques, such as adsorption, membrane filtration, electrocoagulation, photocatalysis, and ion exchange. Among these, the application of nanoparticles emerges as a notable method. The article delves into nano-compounds, optimizing conditions for the fluoride removal process and benchmarking their efficacy against other techniques. Studies demonstrate that advanced nanotechnologies—owing to their rapid reaction times and potent oxidation capabilities—can remove fluoride effectively. The implementation of nanotechnologies in fluoride removal not only enhances water quality but also contributes to the safeguarding of human health. [ABSTRACT FROM AUTHOR]

Pesticides containing chlorine, which are released during agricultural activities, are chemical substances that mix with surface and underground waters and have toxic, carcinogenic, and mutagenic effects on the entire living ecosystem. Due to their chemically stable structure, conventional water and wastewater treatment techniques such as coagulation, flocculation, and biological oxidation do not entirely remove these chemical substances. Therefore, before releasing them into the environmental receptor, these chemical substances must be transformed into harmless products or mineralized through advanced oxidation processes. When we look at the literature, there are not many studies on methods of removing diclofop methyl from aquatic media. Our study on the removal of diclofop methyl herbicide from aquatic media using the peroxy electrocoagulation method will provide the first information on this subject in the literature. In addition, this treatment method will contribute significantly to filling an important gap in the literature as an innovative approach for diclofop methyl removal. Moreover, peroxy electrocoagulation, which produces less sludge, provides treatment in a short time, and is economical, has been determined to be an advantageous process. The effects of conductivity, pH, H2O2 concentration, current, and time parameters on the removal of diclofop methyl were investigated using a GC–MS instrument. Kinetics, energy consumption, and cost calculations were also made. Under the optimum conditions determined (pH = 5, H2O2 = 500 mg/L, NaCl = 0.75 g/L, current density = 2.66 mA/cm2), the peroxydic electrocoagulation process resulted in a diclofop methyl removal efficiency of 79.2% after a 25-min reaction. When the experimental results were analyzed, it was found that the results fitted the pseudo-second-order kinetic model. [ABSTRACT FROM AUTHOR]

The advanced oxidation process (AOP) is an efficient method to treat recalcitrance pollutants such as pharmaceutical compounds. The essential physicochemical factors in AOP experiments significantly influence the efficiency, speed, cost, and safety of byproducts of the treatment process. In this review, we collected recent articles that investigated the elimination of pharmaceutical compounds by various AOP systems in a water medium, and then we provide an overview of AOP systems, the formation mechanisms of active radicals or reactive oxygen species (ROS), and their detection methods. Then, we discussed the role of the main physicochemical parameters (pH, chemical interference, temperature, catalyst, pollutant concentration, and oxidant concentration) in a critical way. We gained insight into the most frequent scenarios for the proper and improper physicochemical parameters for the degradation of pharmaceutical compounds. Also, we mentioned the main factors that restrict the application of AOP systems in a commercial way. We demonstrated that a proper adjustment of AOP experimental parameters resulted in promoting the treatment performance, decreasing the treatment cost and the treatment operation time, increasing the safeness of the system products, and improving the reaction stoichiometric efficiency. The outcomes of this review will be beneficial for future AOP applicants to improve the pharmaceutical compound treatment by providing a deeper understanding of the role of the parameters. In addition, the proper application of physicochemical parameters in AOP systems acts to track the sustainable development goals (SDGs). [ABSTRACT FROM AUTHOR]

• Cobalt doping significantly enhanced the catalytic performance of Co-N/C for PMS activation. • Co doping amount could mediate the conversion of nitrogen-coordinated Co to Co nanoparticles. • Increasing cobalt doping amount could switch the dominant oxidants from singlet oxygen to its coexistence with sulfate radicals and high-valent cobalt. • Nitrogen-coordinated Co mainly contributed to the generation of singlet oxygen. • The synergistic effect of borate and ultra-low concentration Co leached from Co nanoparticles led to produce of sulfate radicals and high-valent cobalt. Switching the reaction routes in peroxymonosulfate (PMS)-based advanced oxidation processes have attracted much attention but remain challenging. Herein, a series of Co-N/C catalysts with different compositions and structures were prepared by using bimetallic zeolitic imidazolate frameworks based on ZIF-8 and ZIF-67 (x Zn/Co-ZIFs). Results show that Co doping amount could mediate the transformation of the activation pathway of PMS over Co-N/C. When Co doping amount was less than 10%, the constructed x Co-N/C/PMS system (x ≤ 10%) was singlet oxygen-dominated reaction; however further increasing Co doping amount would lead to the generation and coexistence of sulfate radicals and high-valent cobalt, besides singlet oxygen. Furthermore, the nitrogen-coordinated Co (Co-N X) sites could serve as main catalytically active sites to generate singlet oxygen. While excess Co doping amount caused the formation of Co nanoparticles from which leached Co ions were responsible for the generation of sulfate radicals and high-valent cobalt. Compared to undoped N/C, Co doping could significantly enhance the catalytic performance. The 0.5% Co-N/C could achieve the optimum degradation (0.488 min−1) and mineralization abilities (78.4%) of sulfamethoxazole among the investigated Co-N/C catalysts, which was superior to most of previously reported catalysts. In addition, the application prospects of the two systems in different environmental scenarios (pH, inorganic anions and natural organic matter) were assessed and showed different degradation behaviors. This study provides a strategy to regulate the reactive species in PMS-based advanced oxidation process. [Display omitted] [ABSTRACT FROM AUTHOR]

The present work deals with the optimization of basic fuchsin dye removal from an aqueous solution using the ultraviolet UV/H2O2 process. Response Surface Modeling (RSM) based on Box-Behnken experimental design (BBD) was applied as a tool for the optimization of operating conditions such as initial dye concentration (10–50 ppm), hydrogen peroxide dosage (H2O2) (10–20 mM/L) and irradiation time (60–180 min), at pH = 7.4 under ultra-violet irradiation (254 nm and 25 W intensity). Chemical oxygen demand (COD abatement) was used as a response variable. The Box–Behnken Design can be employed to develop a mathematical model for predicting UV/H2O2 performance for COD abatement. COD abatement is sensitive to the concentration of hydrogen peroxide and irradiation time. Statistical analyses indicate a high correlation between observed and predicted values (R2 > 0.98). In the BBD predictions, the optimal conditions in the UV/H2O2 process for removing 99.3% of COD were found to be low levels of pollutant concentration (10 ppm), a high concentration of hydrogen peroxide dosage (20 mM/L), and an irradiation time of 80 min. [ABSTRACT FROM AUTHOR]

Cobalt–nitrogen co-doped carbon nanotubes (Co3@NCNT-800) were synthesized via a facile and economical approach to investigate the efficient degradation of organic pollutants in aqueous environments. This material demonstrated high catalytic efficiency in the degradation of carbamazepine (CBZ) in the presence of peroxymonosulfate (PMS). The experimental data revealed that at a neutral pH of 7 and an initial CBZ concentration of 20 mg/L, the application of Co3@NCNT-800 at 0.2 g/L facilitated a degradation rate of 64.7% within 60 min. Mechanistic investigations indicated that the presence of pyridinic nitrogen and cobalt species enhanced the generation of reactive oxygen species. Radical scavenging assays and electron spin resonance spectroscopy confirmed that radical and nonradical pathways contributed to CBZ degradation, with the nonradical mechanism being predominant. This research presents the development of a novel PMS catalyst, synthesized through an efficient and stable method, which provides a cost-effective solution for the remediation of organic contaminants in water. [ABSTRACT FROM AUTHOR]

Herein, a carbon felt (CF) cathode modified by the acidic oxidised carbon nanotubes (OCNTs) exhibited a high yield of the H2O2 generation in electro-Fenton. Rotating disk electrode (RDE) measurements showed that the selective generation of H2O2 occurred on the CF cathode coated by OCNTs (OCNTs/CF), which was attributed to the high amount of oxygen-containing functional groups in OCNTs. Moreover, the pollutant degradation efficiency could almost reach 100% within 60 min in electro-Fenton with OCNTs/CF as the cathode. Furthermore, the pollutant removal efficiency was kept constant after five consecutive cycles, indicating the high stability of OCNTs/CF cathode. Besides, the hydrophilicity of OCNTs/CF cathode was significantly enhanced owing to the abundant oxygen-contained functional groups on the surface of the OCNTs/CF cathode, which facilitated the mass transfer between the OCNTs/CF cathode and the reactants in the bulk solution. To reveal the possible mechanism in electro-Fenton equipped with the OCNTs/CF cathode, quenching experiments and electron paramagnetic resonance (EPR) investigations were further conducted. This work provided valuable insights into the fabrication of the non-metallic cathode with a high ability towards H2O2 generation in electro-Fenton for efficient pollutant removal. [ABSTRACT FROM AUTHOR]

The introduction of the first list of priority pathogenic fungi by the World Health Organization stresses the need to research and develop public health actions to mitigate infections caused by fungi. One of those actions involves the water disinfection systems, which comprise classical and alternative methods that have been developed in the last decades. Thereby, this work reviews the disinfection of fungi by classical methods such as chlorination, ozonation, and ultraviolet (UV) treatments and alternative advanced oxidation processes (AOPs) such as photo-Fenton, photocatalysis, or couplings of UV with peroxides. The matrices of aquatic systems (sewage, groundwater, drinking water, among others) were considered. A bibliometric analysis is performed initially, and then some aspects of the resistance to antifungals are presented, and the efficiency of the diverse processes in the reduction in fungal loading is also revised. Herein, it is shown the role of the disinfecting agents (e.g., chlorine, hydroxyl radical, or light) and their effects on fungi structures (e.g., direct DNA damage, or indirect damage due to the action of radicals). Moreover, gaps, such as the treatment of antifungal-resistant fungi and limited information about combinations among AOPs, related to the disinfection of water polluted by fungi, were identified. [ABSTRACT FROM AUTHOR]

Copyright of Rare Metals is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Metal–organic frameworks (MOFs)-based advanced oxidation processes show great potential in wastewater treatment, while large-scale application is limited by their particle agglomeration and poor recyclability. Herein, a novel three-dimensional (3D) ZIF-67/PAN nanofibrous sponge (ZIF-67/PAN NFS) was successfully fabricated by a convenient method based on a combination of liquid-assisted collection electrospinning, in situ growth and freeze-drying. It was an efficient catalyst for the activation of peroxymonosulfate (PMS). The obtained ZIF-67/PAN NFS exhibited excellent catalytic performance toward the degradation of methylene blue (MB) (99.25% within 30 min). Several influencing factors, such as PMS concentration, temperature, initial pH, and initial MB concentration, were systematically investigated for the degradation of MB. Moreover, the radical quenching experiments proved that SO 4 · - was the predominant reactive species instead of · OH for the degradation of MB. Besides, the ZIF-67/PAN NFS showed excellent reusability and the degradation efficiency remained above 94.36% after five consecutive cycles. This strategy is feasible for the fabrication of novel and efficient catalysts for remediation of organic wastewaters. [ABSTRACT FROM AUTHOR]

Due to industrial and population growth water scarcity has become a global problem. The textile industry is the second largest industry in the world, discarding most of the dye-containing wastewater without treatment. Dyes are carcinogenic organic compounds when mixed with fresh water provide harm to both aquatic and human lives. It is challenging to remove toxic dyes from textile wastewater to keep a clean and green environment. Therefore, the researcher tries to find the latest trends and advances in AOPs. Several treatment methods have been developed to overcome this issue, however, most of them are expensive and provide inefficient removal. The biological process has been used for water treatment. However, it comes with a large amount of sludge production which requires additional costs for handling and disposal. AOPs due to enhanced removal efficiency are widely used for wastewater remediation and sustainability. This review summarizes the recent advances in applying various types of AOPs in treating textile wastewater and discusses the mechanism in detail. This review highlights the gaps and innovative work using different catalysts for treating textile wastewater. Also identifies future challenges and possible solutions for the practical implementation of using AOPs in textile wastewater treatment. [ABSTRACT FROM AUTHOR]

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To address global pollution caused by contaminants in water bodies, it is crucial to develop an efficient and environmentally friendly treatment process for wastewater from various industries. Advanced oxidation processes (AOPs) have proven to be highly effective in wastewater treatment due to their high oxidation efficacy and the absence of secondary pollutants. Different methods such as ozone, Fenton, electrochemical, photolysis, and sonolysis can be used in AOPs to degrade emerging pollutants that are resistant to conventional methods. In recent years, nanotechnology has emerged as a viable solution, with various nanomaterials being developed for wastewater treatment. Among them, copper‐based nanocatalysts have shown great potential in AOPs. This review focuses on the progress and mechanisms of copper‐based nanocatalysts in wastewater treatment via AOPs. It also discusses the challenges associated with oxidation, electrochemistry, Fenton, and photocatalysis in wastewater treatment processes. Copper‐based nanocatalysts can be modified to enhance their catalytic activity, selectivity, and stability, leading to improved performance in wastewater treatment. They have shown promising results in degrading pollutants like pharmaceuticals, pesticides, and dyes. However, the practical application of these nanocatalysts still faces challenges, including the high cost of synthesis, potential nanoparticle toxicity, and scalability issues. More research is needed to address these challenges and improve the utilization of copper‐based nanocatalysts in wastewater treatment. In addition, Cu‐based catalysts with magnetic properties offer the advantage of easy recovery and reusability in wastewater treatment. They can also be incorporated into catalytic membranes, forming efficient systems for recycling. Heterogeneous catalysts with diverse structures, including ternary or quaternary systems, are widely used. However, challenges remain in identifying suitable coupling pairs and understanding the complex processes involved in constructing heterogeneous interfaces without generating defects. Therefore, a thorough understanding of the catalyst's band structure is crucial for developing efficient heterogeneous structures. Furthermore, cost implications of synthesis methods and raw materials should be considered in the preparation of transition metal catalysts, and relevant cost analysis data is needed for optimizing the degradation of pollutants. In conclusion, copper‐based nanocatalysts hold great potential in AOPs for wastewater treatment. With their magnetic properties, Cu‐based catalysts offer the advantage of easy recovery and reusability. However, challenges such as high synthesis costs, nanoparticle toxicity, and scalability issues need to be addressed. Further research is needed to overcome these challenges and optimize the utilization of copper‐based nanocatalysts in wastewater treatment processes. [ABSTRACT FROM AUTHOR]

Photocatalysis emerges as a potential remedy for the issue of an unreliable light source. Recognized as the most dependable and potent energy source sustaining life on Earth, sunlight offers a promising solution. Sunlight is abundant and free, operational costs associated with running photocatalytic system using nanoparticles are often lower compared to system relying on artificial light source. The escalating problem of water pollution, particularly in highly industrialized nations, necessitates effective wastewater treatment methods. These methods aim to combat elevated pollution levels, encompassing pharmaceuticals, dyes, flame retardants, and pesticide components. Advanced oxidation processes within photocatalytic wastewater treatment exhibit substantial promise for removing complex organic pollutants. Doped nanomaterials, with their enhanced properties, enable efficient utilization of light. Coupled nanomaterials present significant potential in addressing both water and energy challenges by proficiently eliminating persistent pollutants from environment. Photocatalysis when exposed to sunlight can absorb photons and generate e- h + pairs. This discussion briefly outlines the wastewater treatment facilitated by interconnected nanomaterials, emphasizing their role in water-energy nexus. In exploring the capabilities of components within a functional photocatalyst, a comprehensive analysis of both simple photocatalysts and integrated photocatalytic systems is undertaken. Review aims to provide detailed explanation of the impact of light source on photon generation and significance of solar light on reaction kinetics, considering various parameters such as catalyst dosage, pH, temperature, and types of oxidants. By shedding light on these aspects, this review seeks to enhance our understanding of intricate processes involved in photocatalysis and its potential applications in addressing contemporary environmental challenges. [ABSTRACT FROM AUTHOR]

This study applied ultraviolet/peroxymonosulfate (UV/PMS) and UV/hydrogen peroxide (UV/H2O2) processes to the advanced treatment of membrane bioreactor (MBR) effluent. The degradation efficiency of refractory organic matter and the reaction mechanisms of the two processes were systematically investigated. The results showed that the degradation efficiency of the UV/PMS processes was significantly lower than that of the UV/H2O2 process when the PMS concentration was significantly lower than the H2O2 concentration, e.g. the UV254 removals under optimal conditions were 72.92% and 82.21%, respectively. Additionally, the UV/PMS process could operate over a broader pH range. The degradation efficiency of the UV/PMS process was slightly increased by HCO3– and Cl- due to the activation of PMS, while in the UV/H2O2 process, HCO3- and Cl- depressed the degradation efficiency by competing with organic matter to react with reactive oxygen species (ROS). After the two processes, the aromaticity, humification, condensation degree, and molecular weight of refractory organic matter in the MBR effluent were considerably decreased. Fulvic- (HA) and humic-like substances (FA) were greatly degraded by the two processes. The UV/PMS had a superior degradation efficiency for macromolecular HA in the early stage of the reaction, and the UV/H2O2 could degrade HA to protein-like substances in the latter stage of the reaction. These differences between the two processes could be attributed to the dominance of different ROS, with SO4•- and HO• dominating in the UV/PMS, and HO• dominating in the UV/H2O2. The results of this study provide theoretical support for the application of MBR effluent treatment. Highlights Comparison on the MBR effluent treatment of UV/PMS and UV/H2O2 is studied. UV/PMS process can better destroy humic-like substances in the early reaction stage. Humic-like substances are transformed into protein-like compounds in UV/H2O2 process. UV/PMS and UV/PMS performs differently due to their different dominant ROS. [ABSTRACT FROM AUTHOR]

A bibliometric study using 1992 to 2021 database of the Science Citation Index Expanded was carried out to identify which are the current trends in textile wastewater treatment research. The study aimed to analyze the performance of scholarly scientific communications in terms of yearly publications/citations, total citations, scientific journals, and their categories in the Web of Sciences, top institutions/countries and research trends. The annual publication of scientific articles fluctuated in the first ten years, with a steady decrease for the last twenty years. An analysis of the most common terms used in the authors' keywords, publications' titles, and KeyWords Plus was carried out to predict future trends and current research priorities. Adsorbent nanomaterials would be the future of wastewater treatment for decoloration of the residual dyes in the wastewater. Membranes and electrolysis are important to demineralize textile effluent for reusing wastewater. Modern filtration techniques such as ultrafiltration and nanofiltration are advanced membrane filtration applications. [ABSTRACT FROM AUTHOR]

Nowadays, antibiotics are widely used, increasing the risk of contamination of the water body and further threatening human health. The traditional water treatment process is less efficient in degrading antibiotics, and the advanced oxidation process (AOPs) is cleaner and more efficient than the traditional biochemical degradation process. The combined ozone/peroxymonosulfate (PMS) advanced oxidation process (O3/PMS) based on sulfate radical (SO4•−) and hydroxyl radical (•OH) has developed rapidly in recent years. The O3/PMS process has become one of the most effective ways to treat antibiotic wastewater. The reaction mechanism of O3/PMS was reviewed in this paper, and the research and application progress of the O3/PMS process in the degradation of antibiotics in drinking water and wastewater effluent were evaluated. The operation characteristics and current application range of the process were summarized, which has a certain reference value for further research on O3/PMS process. [ABSTRACT FROM AUTHOR]

The present work sought to investigate H2O2 generation using a gas diffusion electrode (GDE) composed of carbon with niobium oxide for levofloxacin (LEVO) degradation. Results showed that the oxide formed was Nb2O5 (crystallographic structure was confirmed by XRD; chemical composition detected by XPS), and the increase in the Nb/C ratio led to more crystalline structure and higher crystallite size. The carbon with 5% Nb2O5 presented an average particle size of 5.6 nm, and this material led to the generation of the highest amount of H2O2 (317.6 mg L−1). The C/5% Nb2O5-modified GDE was applied for the degradation of LEVO in an acid medium in the presence and absence of Fe2+ ions. Long-term experiments conducted to analyze the time required for the total removal of LEVO showed that 96% of LEVO and 66% of organic load were removed in 270 min of treatment at the current density of 100 mA cm−2. [ABSTRACT FROM AUTHOR]

In this study, cryptomelane-type manganese oxide (K-OMS-2) was used as a catalyst for the thermal oxidation of toluene. The catalyst was synthesized via the hydrothermal route and doped with Cu, Ce, and co-doped with the same metals by ex-situ and in-situ methods. The effects of dopant type, dopant concentration, and dopant impregnation method on the thermal catalytic activity of K-OMS-2 were examined. Initially, 1%, 2%, and 4% by mole Cu or Ce were incorporated by wet impregnation to the hydrothermally synthesized K-OMS-2 and in-situ direct hydrothermal method. The physicochemical properties were characterized by X-ray diffraction (XRD), N2 adsorption-desorption, X-ray photoelectron spectroscopy (XPS), X-ray absorption near edge structure (XANES), and thermal gravimetric analysis (TGA) techniques. Gaseous toluene was made to react with the doped catalysts in a packed bed reactor attached to gas chromatography equipment to measure the amount of unreacted toluene. Results showed K-OMS-2 doped with 4% by mole Cu and 1% by mole Ce gave excellent thermal catalytic efficiency results at 180 °C reaction temperature. Meanwhile, K-OMS-2 co-doped with Ce and Cu with a mole ratio of 0.25:3.75 per 100 moles of K-OMS-2 gave the best catalytic activity and complete oxidation at 180 °C reaction temperature. Comparing K-OMS-2 doped with the same metal ratios, in situ doped catalysts led to higher toluene removal percentages. Meanwhile, the 72-h stability test showed that the optimum co-doped catalysts are capable of entirely oxidizing toluene even after prolonged and continuous use. [ABSTRACT FROM AUTHOR]

The release of organic contaminants has grown to be a major environmental concern and a threat to the ecology of water bodies. Persulfate-based Advanced Oxidation Technology (PAOT) is effective at eliminating hazardous pollutants and has an extensive spectrum of applications. Iron-based metal–organic frameworks (Fe-MOFs) and their derivatives have exhibited great advantages in activating persulfate for wastewater treatment. In this article, we provide a comprehensive review of recent research progress on the significant potential of Fe-MOFs for removing antibiotics, organic dyes, phenols, and other contaminants from aqueous environments. Firstly, multiple approaches for preparing Fe-MOFs, including the MIL and ZIF series were introduced. Subsequently, removal performance of pollutants such as antibiotics of sulfonamides and tetracyclines (TC), organic dyes of rhodamine B (RhB) and acid orange 7 (AO7), phenols of phenol and bisphenol A (BPA) by various Fe-MOFs was compared. Finally, different degradation mechanisms, encompassing free radical degradation pathways and non-free radical degradation pathways were elucidated. This review explores the synthesis methods of Fe-MOFs and their application in removing organic pollutants from water bodies, providing insights for further refining the preparation of Fe-MOFs. [ABSTRACT FROM AUTHOR]

A large variety of pharmaceutical compounds have recently been detected in wastewater and natural water systems. This review highlighted the significance of removing pharmaceutical compounds, which are considered indispensable emerging contaminants, from wastewater and natural water systems. Various advanced oxidation processes (AOPs), including UV-H2O2, Fenton and photo-Fenton, ozone-based processes, photocatalysis, and physical processes, such as sonolysis, microwave, and electron beam irradiation, which are regarded as the most viable methods to eliminate different categories of pharmaceutical compounds, are discussed. All these AOPs exhibit great promising techniques, and the catalytic degradation process of the emerging contaminants, advantages, and disadvantages of each technique were deliberated. Heterogeneous photocatalysis employing metal oxides, particularly anatase TiO2 nanoparticles as catalysts activated by UV light irradiation, was reviewed in terms of the electron–hole separation, migration of the charge carriers to the catalyst surfaces, and redox potential of the charge carriers. This brief overview also emphasized that anatase TiO2 nanoparticles and TiO2-based nanomaterials are promising photocatalysts, and a combination of photocatalysis and other AOPs enhanced photocatalytic degradation efficiency. Finally, the challenges of applying anatase TiO2-based photocatalysis in environmental remediation and wastewater treatments to degrade pharmaceutical compounds, including mass spectroscopic analysis and a biological activity test of by-products of the emerging contaminants resulting from photocatalysis, are summarized. [ABSTRACT FROM AUTHOR]

Co-precipitation was employed to synthesize copper-based layered double hydroxides, which were subsequently utilized as heterogeneous catalysts for the ozonation of 4-nitrophenol in aqueous solutions. Various analytical techniques, including X-ray diffraction (XRD), Fourier-transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM), and thermogravimetric analysis (TGA), were utilized to characterize CuAl-CO3 and CuAl500.The catalytic activity of CuAl-CO3 was evaluated under different reaction conditions. Notably, at pH 11 and 25 °C, CuAl-CO3 exhibited high catalytic efficiency in the ozonation of 4NP. Increasing the catalyst dose, initial pH, and temperature led to enhanced 4NP degradation. An optimal pH of 11 and a catalyst dose of 0.3 g. L−1 resulted in the removal of 78.6% of the initial 4NP concentration. Additionally, ozonation proved to be more efficient at temperatures of 10 °C and 55 °C. The kinetics of 4NP ozonation over CuAl-CO3 and CuAl500 followed a pseudo-first-order reaction. Furthermore, the study demonstrated that CuAl-CO3 and CuAl500 exhibited stability and repeatability across multiple reaction cycles, highlighting their potential for continuous catalytic applications. Overall, this research emphasizes the effectiveness of CuAl-CO3 and CuAl500 as reliable heterogeneous catalysts for the ozonation of 4NP. The results contribute valuable insights into the development of advanced oxidation processes for the treatment of wastewater containing organic contaminants. [ABSTRACT FROM AUTHOR]

Advanced oxidation processes are emerging technologies for the decomposition of organic pollutants in various types of water by harnessing solar energy. The purpose of this study is to examine the physicochemical characteristics of tungsten(VI) oxide (WO3) photoanodes, with the aim of enhancing oxidation processes in the treatment of water. The fabrication of WO3 coatings on conductive fluorine-doped tin oxide (FTO) substrates was achieved through a wet coating process that utilized three different liquid formulations: a dispersion of finely milled WO3 particles, a fully soluble WO3 precursor (acetylated peroxo tungstic acid), and a combination of both (applying a brick-and-mortar strategy). Upon subjecting the WO3 coatings to firing at a temperature of 450 °C, it was observed that their properties exhibited marked variations. The fabricated photoanodes are examined using a range of analytical techniques, including profilometry, thermo-gravimetric analysis (TGA), X-ray diffraction (XRD), and voltammetry. The experimental data suggest that the layers generated through the combination of particulate ink and soluble precursor (referred to as the brick-and-mortar building approach) display advantageous physicochemical properties, rendering them suitable for use as photoanodes in photoelectrochemical cells. [ABSTRACT FROM AUTHOR]

Chlorine and solar disinfection are widely used disinfectants in water treatment. However, certain potential pathogens can resist these methods, posing a public health risk. One such case is Acanthamoeba, a resistant free-living amoeba that protects pathogens inside from disinfection, thus endangering the health of water users. This work is the first evaluation of the inactivation efficiency achieved by combining NaClO (Cl2) and solar radiation (SR) against two Acanthamoeba strains from different sources (freshwater and pool water) and their endosymbiont bacteria (EB). Amoebae were exposed to different Cl2 doses (0–500 mg/L), SR wavelength ranges (280–800 nm and 320–800 nm), used as gold standards, and their combinations. The EB exhibited resistance to conventional Cl2 and SR treatments, requiring up to 20 times higher disinfectant doses than those needed to inactivate their protective Acanthamoeba. The pool strain and its EB demonstrated greater resistance to all treatments compared to the freshwater strain. Treatments with Cl2 (5 mg/L)/SR280–800nm completely inactivated both Acanthamoeba and EB of the freshwater strain, reducing up to 100 times the necessary Cl2 doses, suggesting that chlorine photolysis is an attractive treatment for disinfecting freshwater and preventing waterborne diseases associated with Acanthamoebae and its EB. [ABSTRACT FROM AUTHOR]

New technologies are providing opportunities for the design of novel educational methodologies. Virtual laboratories can simulate real conditions, thus reducing the workload of teachers and students, and removing the costs associated with laboratory or pilot plant tests. The present work describes the creation of a virtual and interactive lab using the Easy JavaScript Simulation (EJsS) 6.0 tool. The solar photo‐Fenton process for the degradation of the Acetamiprid pesticide (ACTM) as a micropollutant model in wastewater was implemented in discontinuous mode in a stirred tank reactor (STR) and in continuous mode in a raceway pond reactor (RPR). The objective was to achieve a virtual tool that would allow easy, intuitive connection to different devices (laptops, tablets, and smartphones), simplifying the difficulties related to teaching technology. This contribution details the design and implementation process of the model for its use as support material for theoretical classes. The virtual tool presented in this article is an example of how the EJsS platform can be used to teach dynamics systems in chemical engineering. [ABSTRACT FROM AUTHOR]

تعتبر المياه المصاحبة للنفط من أخطر أنواع التلوث على البيئة، لأنها تحتوي على العديد من الملوثات الضارة بالبيئة وصحة الإنسان مثل (النفط، المواد الصلبة العالقة، المواد الذائبة، والعديد من الملوثات الأخرى). يتناول هذا المقال عمليات الأكسدة المتقدمة (AOPs) التي تمت دراستها لتنقية المياه المنتجة من حقل الخباز النفطي الواقع في شمال العراق - محافظة كركوك من المحتوى النفطي. نظرًا لسهولة استخدام AOPs والأداء والسعر المنخفض، فهي طريقة شائعة لتنقية هذا النوع من مياه الصرف الصحي. في هذا العمل تم استخدام عمليات التحفيز الضوئي المتجانسة (Photo-Fenton (H2O2+Fe+2+UV)،) Fenton (H2O2+Fe+2، وUltra Violet (UV) فقط) في نظام الدفعات تحت أفضل الظروف (الزمن = 120 دقيقة، الرقم الهيدروجيني = 2.5، H2O2 = 20 مل في عملية فوتو فنتون، H2O2 = 80 مل في عملية فنتون، 2 مصباح UV (قدرة كل واحد = 8 وات) في عملية فوتو فنتون، 10 مصابيح UV في عملية UV مباشرة، و Fe+2=18 مجم في عمليات فوتو فنتون وفنتون). تم في هذا البحث دراسة تأثير جرعات H2O2 وFe+2 وزمن التشعيع وقيمة الرقم الهيدروجيني وشدة الأشعة فوق البنفسجية على فعالية إزالة النفط. حققت هذه الدراسة أعلى كفاءة في الفوتو-فنتون هي 85.68%، الفنتون= 75.01%، والتحليل الضوئي فوق البنفسجي المباشر= 56.64%. ونتيجة لذلك تم التوصل إلى أن عملية الفوتو فنتون هي أفضل طريقة لإزالة النفط من المياه المصاحبة للنفط.

The wastewater containing both Cr（Ⅵ） and dyes is frequently produced in the industrial manufacturing processes including printing and dyeing，tanning，etc. Based on the concept of “treating waste with waste”，the feasibility of simultaneous removal of Rhodamine B（RhB） and Cr（Ⅵ） by activating sulfite with Cr（Ⅵ）（Cr（Ⅵ）/S（Ⅳ） system） was investigated. The active species in the reaction system were identified，and the effects of initial concentrations of Na2SO3 and Cr（Ⅵ），the initial pH and the amount of dissolved oxygen on the degradation of RhB and Cr（Ⅵ） were investigated. The results showed that，at the initial pH was 3，95.1% of RhB and 87.4% of Cr（Ⅵ） was removed within 60 min by 1.00 mmol/L Na2SO3 and 0.15 mmol/L Cr（Ⅵ）. The dissolved oxygen was involved in the conversion of sulfur-oxygen free radicals in the reaction process，and played a key role in the degradation of RhB and the reduction of Cr（Ⅵ）. The finding of EPR detection and quenching experiments demonstrated that，SO4·-，SO5·-，·OH and 1O2 cooperatively engaged in the reaction process of Cr（Ⅵ）/S（Ⅳ） system，in which SO4·-is the main active species. Meanwhile，the contribution of 1O2 formed from SO4·-should not be ignored. In addition，the possible degradation pathway of RhB was proposed according to the results of ultraviolet full-wavelength scanning and GC/MS.

Advanced oxidation processes are emerging technologies for the decomposition of organic pollutants in various types of water by harnessing solar energy. The purpose of this study is to examine the physicochemical characteristics of tungsten(VI) oxide (WO3) photoanodes, with the aim of enhancing oxidation processes in the treatment of water. The fabrication of WO3 coatings on conductive fluorine-doped tin oxide (FTO) substrates was achieved through a wet coating process that utilized three different liquid formulations: a dispersion of finely milled WO3 particles, a fully soluble WO3 precursor (acetylated peroxo tungstic acid), and a combination of both (applying a brick-and-mortar strategy). Upon subjecting the WO3 coatings to firing at a temperature of 450 °C, it was observed that their properties exhibited marked variations. The fabricated photoanodes are examined using a range of analytical techniques, including profilometry, thermo-gravimetric analysis (TGA), X-ray diffraction (XRD), and voltammetry. The experimental data suggest that the layers generated through the combination of particulate ink and soluble precursor (referred to as the brick-and-mortar building approach) display advantageous physicochemical properties, rendering them suitable for use as photoanodes in photoelectrochemical cells.

Nanofiltration (NF) has been used as the default sulfate removal process in platforms to treat seawater for water flooding. Seawater is generally pretreated by chlorination and cartridge filters to reduce fouling of the membranes; however, this pretreatment is insufficient to provide water quality high enough to maintain the productivity of the NF membranes. In this study, the performances of two different pretreatment routes were evaluated. Microfiltration (MF) was evaluated as a replacement for cartridge filters, and the advanced oxidation process UV/H2O2 was evaluated as an additional stage of pretreatment upstream of the cartridge filters. The permeability of the NF membranes after 12 h of seawater sulfate removal in a bench system was 4.4 L·h−1·m−2·bar−1 when the UV/H2O2 process was adopted as the pretreatment and 2.9 L·h−1·m−2·bar−1 when the MF process was adopted, compared to 1.6 L·h−1·m−2·bar−1 achieved for the pretreatment with the cartridge filter alone. These results indicate that NF membrane fouling was significantly higher when seawater was pretreated only by the cartridge filter in comparison to both proposed pretreatments. An economic analysis showed that both systems are economically viable and can potentially reduce the operational costs of the NF sulfate removal process on platforms. HIGHLIGHTS Comprehensive analysis of cartridge filters, microfiltration, and advanced oxidation process UV/H2O2 pretreatments for seawater desalination by nanofiltration, the last which has not been well stated in the literature.; UV/H2O2 impact on reducing seawater fouling in membranes.; Economic analysis showing the impact on operational costs of the pretreatments on the nanofiltration sulfate removal process in offshore platforms.;