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The electrochemical desalination technique is recognized as a promising solution to alleviate freshwater shortages, challenges yet persists in achieving optimal energy efficiency and cost‐effectiveness. Herein, a hybrid acid/alkali zinc air desalination battery (hAA‐ZADB) capable of concurrent desalination and high‐power density is reported. To improve cathodic efficiency and cost‐effectiveness, an electrocatalyst with dual atomic Fe–Mn sites on porous dodecahedral carbon (Mn‐Fe/p‐DC) is fabricated through a simple direct pyrolysis strategy for oxygen reduction reaction (ORR). The Mn–Fe/p‐DC‐900 electrocatalyst demonstrates exceptional electrocatalytic activity (E1/2 = 0.8 V in 0.5 m H2SO4) for ORR. This innovative hybrid acid/alkali cell design, coupled with advanced electrocatalysts, empowers the hAA‐ZADB system to achieve outstanding performance benchmarks with a high open circuit voltage of 2.22 V, an impressive power density of 375 mW cm−2, and notably elevated energy output of 106.9 kJ mol−1 even at a current density of 100 mA cm−2 during desalination. Distinguishing this work is its additional functionality, evident in a rapid salt removal rate of 3.64 mg cm−2 min−1 during desalination, achieving an impressive 88.67% removal of 0.6 M NaCl. This study highlights the promising potential of employing metallic air batteries for a self‐powered desalination technique applicable to specific scenarios. [ABSTRACT FROM AUTHOR]

In view of water eutrophication, global energy crisis and the carbon neutrality policies, the ammonia recovery from wastewater with high efficiency and low energy consumption is crucial for preserving the ecological environment and achieving sustainable development. Transmembrane electro-chemisorption (TMECS), which integrates transmembrane chemisorption with electrochemical systems to reduce the addition of chemicals and improve recovery efficiency, is a promising technology for ammonia recovery from wastewater. Accordingly, this paper first reviews the recent advances in TMECS for ammonia recovery from wastewater. In particular, the technology principles, including ammonia stripping by cathodic base, ammonia recovery by TMECS with authigenic acid and base, and ammonia recovery by membrane cathode with in situ cathodic base are elucidated. Couplings of TMECS with other electrochemical systems, including electrodialysis, flow-electrode capacitive deionization, and electrochemical precipitation, are further summarized and compared. Finally, the challenges and prospects of the TMECS technology are addressed. [ABSTRACT FROM AUTHOR]

Excessive phosphorus discharge causes water eutrophication and disturbs the homeostasis of aquatic ecosystems. Capacitive deionization (CDI) has been proven to be a more energy-efficient and environmentally friendly technology for removing phosphorus. Raw carbon (Raw C) electrodes are widely used in CDI. However, the phosphorus removal capacity of most unmodified Raw C still needs to be enhanced. Therefore, the Fe, N-co-doped carbon prepared in this study was expected to further improve the phosphorus removal performance. Herein, the optimal electrode with 5% Fe (FeNC) had an approximately 2.7 times higher adsorption capacity than Raw C. At a low concentration (5 mg P/L), FeNC exhibited a high maximum removal capacity of 4.28 mg P/g. Under reversed voltage, the phosphorus was easily desorbed by deionized water. Ion competition studies showed that coexisting ions adversely affected phosphorus adsorption onto FeNC in the order SO42- > NO3- > Cl-. Furthermore, the energy consumption of FeNC was calculated to be as low as 0.0069 kWh/g P and 0.023 kWh/m3 water under 1.2 V. More importantly, phosphorus removal by FeNC during CDI was demonstrated in simulated natural water from the Jinjiang River (Chengdu, China). This study indicated that FeNC is expected to be a potential electrode for CDI dephosphorization. [ABSTRACT FROM AUTHOR]

The reciprocating plate column is a kind of column with the plates driven by a geared motor, and it has advantages in regard to efficiency compared to traditional columns in the extraction process, however, it comes with an increase in energy consumption. A new type of reciprocating plate column driven by electro-permanent magnet technology (EPM) is proposed in this paper to obtain a better performance with lower energy consumption. The feasibility and performance of the proposed column is studied by numerical simulation and experiments with a kerosene–water system. The electro-permanent magnet chuck could provide a maximum amplitude of 12 mm in this study. Kerosene was used as the dispersed phase, and deionized water was used as the continuous phase, in a laboratory-scale 35 mm diameter reciprocating plate column driven by EPM. Hydrodynamic performance experiments were carried out with different flowrates of both phases and reciprocating frequencies. The experimental results show that the electro-permanent magnet chuck, which serves as the driving device of the reciprocating plate column, plays the role of adding energy and increasing the droplet breakage. In addition, the energy consumption of the reciprocating plate column with traditional geared motor and electro-permanent magnet chuck is calculated respectively. Compared with the traditional geared motor, the energy saving of the electro-permanent magnet chuck is as high as 98.55%. [ABSTRACT FROM AUTHOR]

Freshwater resources are limited; thus, different technologies for desalination of brackish and seawater have been developed. Capacitive deionization (CDI) is one of the most promising desalination technologies owing to its low cost, simplicity, nonmoving parts, and low energy consumption. However, its energy consumption significantly increases with desalination of high-salinity water. In this regard, a good understanding of the effects of different process parameters on CDI energy consumption is crucial for further performance improvement. Therefore, the surface response methodology (RSM) was adopted to systematically study the effects of applying voltage, Stern layer capacity, volume and concentration of feed water, and volume of micropores on energy consumption and desalination time. The results showed that the Stern layer capacity and volume of micropores reduced desalination time by approximately 25% without significant changes in energy consumption. With the design of an improved electrode (improving the micropore structure for ion adsorption), the desalination time (Cycle) was reduced and a slight reduction in energy consumption was achieved. It can be claimed that any improvement in the physical (porosity) and electrical properties of the electrodes, results in an important increase in the performance of the CDI system. [ABSTRACT FROM AUTHOR]

This study uses electrochemical technology to simultaneously remove salt and degrade organic pollutants to achieve green and efficient treatment of high-salt organic wastewater. In this study, graphene oxide (GO), which has excellent conductivity, chemical stability, and catalytic adsorption performance, was selected to prepare a composite electrode, aiming to explore its performance and evaluate its possibility of being used for the degradation of high-salt phenol wastewater treatment. The samples were characterized using SEM, FTIR, and other techniques. The electrochemical performance of the samples was analyzed using an electrochemical workstation, and their practical application performance was explored through simulated wastewater experiments. Experimental results confirmed that among the three electrodes prepared, the CFGE exhibited the lowest system energy consumption and the highest current efficiency, measuring 235.81 kWh/kgCOD and 12.66 % respectively. The HGE electrode is second only to it, with 269.39 kWh/kgCOD and 11.08 % respectively. The SCGE electrode has the worst performance, which is 344.83 kWh/kgCOD and 8.66 % respectively. The Yst of the three electrodes are 0.4083 mg/L-min, 0.3817 mg/L⋅min, and 0.29 mg/L⋅min respectively. This study provides new research ideas and solutions for the efficient treatment of high-salt organic wastewater. [ABSTRACT FROM AUTHOR]

In recent years, the evolution of lithium-ion batteries (LIB) has been propelled by the growing demand for energy storage systems that are lightweight, have high energy density, and are long-lasting. This review article examines the use of self-terminated oligomers with hyperbranched architecture (STOBA) as a key electrode additive for the superior performance of LIBs. STOBA has been found to have excellent electrochemical properties, including high specific capacity, low impedance, and good cycling stability when used as an additive in electrode materials. The article discusses the process of synthesis and characterization of STOBA materials, including their potential applications in LIBs as electrode material additives. The article also discusses current research on the optimization of STOBA materials for LIBs, including the use of different solvents, monomers, and initiators. Overall, the review concludes that STOBA materials possess huge potential as a next-generation additive for LIB safety. [ABSTRACT FROM AUTHOR]

Flow-electrode capacitive deionization (FCDI) offers an electrochemical, energy-efficient technique for water desalination. In this work, we report the study of carbon-based FCDI, which consists of one desalination chamber and one salination chamber and applies a carbon nanomaterials-based flow electrode that circulates between the cell anode and cathode, to achieve a fast, continuous desalination process. Five different carbon nanomaterials were used for preparing the flow electrode and were studied for the desalination performance, with properties including average salt removal rate (ASRR), salt removal efficiency (SRE), energy consumption (EC) and charge efficiency (CE) being quantitatively determined for comparation. Different FCDI parameters, including carbon concentration and flow rate of the flow electrode and cell voltage, were investigated to examine the influences on the desalination. Long-term operation of the carbon-based FCDI was evaluated using the optimal results found in the conditions of 1.5 M concentration, 1.5 V cell voltage, and 20 mL min−1 flow rate of electrode and water streams. The results showed an ASRR of 63.7 µg cm−2 min−1, EC of 162 kJ mol−1, and CE of 89.3%. The research findings validate a good efficiency of this new carbon-based FCDI technology in continuous water desalination and suggest its good potential for real, long-term application. [ABSTRACT FROM AUTHOR]

Solar steam generation has emerged as an environment‐friendly and promising strategy to overcome the freshwater and energy crisis. However, simultaneously attaining the satisfied evaporation rate, durability and energy utilization in a single system is challengeable, but crucial to the practical application. Herein, inspired by the carpet weaving technique and benefiting from "fiber–yarn–fabric" hierarchical structures, a 3D fabric evaporator with vertical hemp‐yarn arrays is innovatively constructed, featuring a combined structure of multiscale pores from tunable spacing between adjacent fibers or yarns, the vertically aligned architecture coated with superhydrophilic MXene‐sandwiched layer and the adjustable side height/areas. These structures work cooperatively, surprisingly achieving the integrated functions of excellent light capture, the balanced evaporation area and vapor escape space, the additional energy adsorption from the environment and the salt exchange along or between micro/macro pores. Consequently, the 3D evaporator exhibits an outstanding evaporation rate (3.95 kg m−2 h−1 under one‐sun illumination) and extremely high outdoor evaporation (47.04 kg m−2 for 8 h), accompanied with outstanding salt‐resistance (continuous 120 h in 14% brine without salt accumulation), anti‐oilfouling and anti‐bacterial (efficiency over 99.9%) performances. Finally, through rationally assembling multi‐function modules with a condenser, an all‐in‐one "desalination–thermoelectricity–irrigation" platform is built, realizing the maximum utilization of steam condensation enthalpy. [ABSTRACT FROM AUTHOR]

[Display omitted] • BiOCl/MXene composite was synthesized via a hydrothermal reaction. • The effect of MXene on the morphology of BiOCl was studied. • PDDA was used to adjust the electronegativity of the MXene surface. • PDDA modified BiOCl/MXene has high dichlorination ability and cycling stability. • Capacitive deionization (CDI) was simulated using COMSOL Multiphysics. Currently, chloride ions in industrial water limits its reuse when extending the circulating water cycle. Therefore, it is necessary to remove Cl− to ensure its effective reuse. Considering the development of new materials for efficient electrochemical chloride removal is a key issue limiting the development of capacitive deionization technology for chlorine removal. In this study, BiOCl was grown in situ on the surface of V-MXene, and then a nanoflower-like BiOCl/MXene composite was synthesized by utilizing the properties of MXene as a structure-directing agent to modulate the morphology, which exhibits superior pore structure and specific capacitance. The poly (diallyl dimethylammonium) (PDDA) modification improved the materials' specific capacitance and reduced energy consumption for dichlorination. The optimal BMP-10 exhibited superior performance for dichlorination, the maximum dichlorination capacity and rate were 161.64 mg g−1 and 2.20 mg g−1 min−1. We found that MXene has excellent properties for exfoliation and morphology modulation of layered materials. Additionally, the electrical properties have an important influence on the electrochemical removal of chloride ions. Here we successfully synthesized an efficient electrode material with unique morphological structure for CDI dichlorination and provided ideas for structure-directing agents and electrical modulation in material design for electrochemical dichlorination. [ABSTRACT FROM AUTHOR]

Boron presents challenges in desalination owing to its small size and lack of charge. While various methods, such as reverse osmosis, capacitive deionization, and electrodeionization, have been utilized to control boron, they often suffer from high levels of energy consumption and complex processes requiring pH adjustment to generate the charged form of boron. Herein, we introduce a novel approach, i.e., redox-mediated electrodialysis (redox-ED) assisted by ion-exchange resins, aimed at energy-efficient boron control without requiring pH adjustment. Our system displays a remarkable boron removal efficiency of 99% with a low energy consumption of 0.009 kWh/g (0.09 kWh/m3). These results are likely due to the dissociation of water on the surface of the ion-exchange resins, which led to a local pH gradient and reduced systemic resistance through additional ion flux. Furthermore, via techno-economic analysis, the total cost of the redox-ED for boron removal revealed a 50% reduction with the scale-up strategy of electrode stacking, compared to those of traditional EDI systems. Overall, this study demonstrates the new potential of a sustainable boron removal technology without pH adjustment through the redox-ED system assisted by ion-exchange resins, providing an attractive option applicable to the boron removal industry. [Display omitted] [ABSTRACT FROM AUTHOR]

This study focused on removing salts and nutrients (nitrogen and phosphorus) from tertiary treated urban wastewater by capacitive deionization. The performance of a pilot-scale radial capacitive deionizer subjected to varying feed flow rates during the purification stage and constant flow rates during the reject stage was evaluated. This operational strategy aimed to maximize the water recovery rates of the system, with electrical adjustments being made proportionally to the water recovery rate. Lower hydraulic loads resulted in the radial capacitive deionizer removing more ions from the sewage, albeit with higher specific energy consumption. Optimal operational conditions reduced conductivity by 92.8 %, with a specific energy consumption of 2.17 kWhm−3. Significant removals of ammonium, nitrite, nitrate, and orthophosphate ions were observed, with average specie reductions of up to 84, 91.4, 100, and 60.5 %, respectively. Higher rates of treated water recovery resulted in lower ion removal reduction and energy consumption. The limiting step of the process referred to ion desorption, requiring the correct adjustment of the time lapse, flow rate, and applied electrical voltage to ensure the efficiency of the subsequent purification stage. A loss of efficiency was observed when the process was run continuously, thus emphasizing the strategic significance of capacitor rinsing during the rejection phase across multiple subsequent treatment cycles. • Significant removals of NH 4 +, NO 2 −, NO 3 −, and PO 4 3− from the effluent were observed. • The lower the hydraulic loads, the higher the removing rates of ions from the sewage. • The best ions removals were achieved with the higher specific energy consumption. • The limiting step of the process was the ion desorption during capacitor rinsing. [ABSTRACT FROM AUTHOR]

[Display omitted] • A novel two-stage FCDI (TS-FCDI) configuration is proposed. • PANI-CC-AC freestanding electrode construction by one-pot ectropolymerization method. • Secondary ion transfer between the two types of electrodes improves the desalination performance of TS-FCDI. • Role of the two types of electrodes in deionization process was comprehensive analyzed. The desalination of seawater/wastewater utilizing flow-electrode capacitive deionization (FCDI) has received significant interest. However, challenges like the low electrical conductivity of flow electrode and excessive energy consumption have prevented the scaling up of desalination operations. To overcome these issues, this study introduces a new FCDI system termed the two-stage FCDI (TS-FCDI) system, in which desalination modules are equipped with freestanding and flow electrode. The TS-FCDI system offers a graded desalination module design that produces an average salt removal rate (ASRR) of 113 µg cm2·min−1. However, the TS-FCDI system requires substantially reduced infrastructure investment, device size, and energy expenses. Notably, the design allows for the simultaneous operation of freestanding and flow electrode and enables the transport of ions and charges in the electrode region. Experimental evidence from multiple device configurations (CDI, FCDI, and TS-FCDI) supports this claim. Notably, the TS-FCDI system shows about twice the desalination performance over FCDI, with approximately 50 h of single-cycle (SC) operation. This enhancement links the freestanding electrode with the flow electrode, enabling the device to be well-suited for practical applications. The continuous flow of electrode particles in contact with the freestanding electrode initiates secondary ion transport, merging two different types of electrodes to enhance the active space of the electrode, effectively improving ion adsorption performance. In summary, the results of this study indicate the potential of the TS-FCDI system as a suitable desalination technology for scaling up applications. [ABSTRACT FROM AUTHOR]

The growing demand for rare earth elements (REEs) necessitates cheap and environmentally friendly technologies for REEs recovery. Herein, we fabricated a pyrrolic-N doped activated carbon electrode (PPyN-AC) via two facile steps of in-situ polymerization of pyrrole monomers and further carbonization. Capacitive deionization (CDI) using PPyN-AC as electrodes is the first time applied for REEs capture from aqueous solution. PPyN-AC possesses a high N doping rate (9.55 at.%) and excellent capacitance (128.98 F/g). The CDI flow-by tests shows that the electrosorption capacity of La(III) by PPyN-AC electrode was 23.66 mg/g within 25 min at optimal conditions. The rapid and efficient La(III) electrosorption performance is attributed to the pyrrole-N configuration in the carbon matrix. Beyond that, the PPyN-AC electrode could selectively capture La(III) from a quaternary-component system of La(III), Fe(III), Ca(II) and Na(I) in aqueous solution. The REE selectivity mechanism, which involves the ionic charge, hydrated radii of metal ions, and hard-soft Lewis acid-base principle, was proposed. Overall, this work demonstrates a new efficient approach for the selective recovery of REEs from aqueous solution with minimal land and energy demands. The study reported a straight route to prepare pyrrolic-N doped AC serving as capacitive deionization electrode for the recovery of REEs from wastewater. The proposed PPyN-AC electrode exhibits excellent selectivity toward La(III) in the presence of competitive ions. [Display omitted] • Capacitive deionization (CDI) system for REEs recovery is first proposed. • CDI realized 23.66 mg/g La(III) uptake within 25 min by PPyN-AC electrode. • PPyN-AC selectively electrosorbed La(III) from a mixture of La–Fe–Ca–Na. • The pyrrole-N configuration contributes in the selective capture of REEs. [ABSTRACT FROM AUTHOR]

Capacitive deionization (CDI) shows promising potential for water desalination due to its high performance, energy efficiency, and environmental friendliness. Because of their excellent conductivity, chemical stability, and high surface area, carbon derivatives are the most used capacitive deionization electrode materials. Among these carbon materials, graphene is quite attractive because of its exceptional electrical conductivity and very large surface area compared with other carbon materials. In addition to the low energy requirements of the CDI that in many scenarios outperforms reverse osmosis, further reduction in the energy can be realized through recovering some of the input energy. The recovered energy can be used to power additional CDI cells, stored in other energy storage devices such as supercapacitors, or used in any other application. This study summarizes recent progress in implementing graphene as an electrode material for CDI and the different methods used for recovering energy from CDI cells. Furthermore, the energy consumption in CDI with and without energy recovery is compared with the most common desalination technologies such as reverse osmosis, multiple-effect distillation, and multistage flash distillation. [ABSTRACT FROM AUTHOR]

Rapidly changing demand on energy storage systems makes it essential to redesign the device architecture and materials required to fabricate the devices. It is crucial to introduce capacitive behaviour in a conventional energy storage device (batteries) to improve the lifetime and power efficiency of the hole energy storage system. The charge storing nature of electrode material primarily depends on particle size, grain size, the electrode’s chemical structure, and effective diffusion lengths for electrolytes within the electrode. Here V2O5 based Li-ion battery electrode is transformed into a Li-ion pseudocapacitive electrode by structural modifications. The modified structures are achieved by optimizing reaction pressure to obtain larger, medium and smaller V2O5 particles (namely, V2O5-L, V2O5-M and V2O5-S). As a result, the plateau regions in galvanostatic chargeâ€"discharge plots and highly intense redox peaks in the CV plots of V2O5-L get flattened for V2O5-S. Also, the lucrative improvement in rate capabilities and stability for V2O5-S indicates induced pseudocapacitance in V2O5. Some devices are fabricated with the extrinsic pseudocapacitive material (V2O5-S), providing 4.36 mWh cmâˆ'3 volumetric energy density with 125 mW cmâˆ'3 volumetric power density. The device retains around 95% of its initial capacitance after 10k cycles and holds up to 63% after 25k stability cycles. [ABSTRACT FROM AUTHOR]

Electrochemical conversion of CO2 to fuels powered by renewable energy is an attractive technology for carbon emission reduction and renewable energy utilization elevation. Here, electrochemical reduction of CO2 to selectively produce CO using a homemade electrolyzer and Au nanocatalyst was investigated. Au nanoparticles were uniformly anchored on N-doped carbon to improve catalytic activity, and the C/N ratio and operating temperature were adjusted to elevate catalytic selectivity. The resulting Au catalyst exhibited a current efficiency for CO production higher than 90% in a wide full cell voltage range (1.8 ~ 3.0 V), a high mass activity of 900 A gAu -1, and a total current density of 200 mA cm-2 under 3.0 V cell voltage at room temperature. A scale-up 3 × 3 cm CO2 electrolyzer was constructed and tested at 1 A, the current efficiency for CO production reached 93% but decreased within a few hours due to the potassium carbonate precipitation phenomenon at the cathode. The important influence of an unideal ion transport pathway during electrolysis on CO2 electrolyzer performance was revealed, and its stability can be greatly improved by using deionized water instead of KOH solution. [ABSTRACT FROM AUTHOR]

[Display omitted] • A fundamental understanding of Prussian blue and its analogues for superior capacitive deionization is provided. • The advantages and challenges of Prussian blue and its analogues for capacitive deionization are explained. • The directions for future research and development are determined from a perspective of nanoarchitectonics. Capacitive deionization (CDI) offers an appealing electrochemical solution for water treatment, where electrode materials play a crucial role in ensuring the efficiency of CDI devices. The quest for novel electrode materials is driven by the need to enhance desalination capacity, cycling stability, ion selectivity, and energy efficiency, given that traditional carbon materials relying on electric double layer electrosorption principle often exhibit subpar desalination capabilities. Among the standout options, Prussian blue (Fe 4 [Fe(CN) 6 ] 3) and its analogs (PB/PBAs) have stood out in CDI systems due to their superior performance and durability as coordination polymers. Nevertheless, challenges persist in leveraging their full potential for CDI, stemming from issues like low desalination capacity, slow kinetics, poor conductivity, structural vulnerability, and limited electrochemical activity. Recent years have witnessed the emergence of innovative strategies aimed at addressing these obstacles, particularly through advancements in structural and compositional manipulation. This review seeks to consolidate the latest advancements in the nanoarchitectonics of PB/PBAs, exploring their classification, and synthesis methodologies, and delving into the fundamental principles governing their utility in CDI applications—anchored in considerations of thermodynamics, kinetics, and mechanisms. Notably, the review underscores the prevailing challenges faced by PB/PBAs in CDI deployment, prompting the discussion of proactive approaches to guide future material innovation and usage. By shedding light on the ongoing efforts to enhance PB/PBAs for CDI, this review anticipates that advancements in nanoarchitectonics will unlock fresh possibilities in the realm of high-performance CDI material design and implementation. [ABSTRACT FROM AUTHOR]

[Display omitted] • A review of electrochemical lithium extraction based on electrodialysis and capacitive deionization is provided. • The advantages and challenges of electrochemical lithium extraction technologies are explained. • The directions for future research and development are determined. Efficient lithium extraction and separation technologies are increasingly imperative owing to the rising demand for lithium in energy storage and electronics. However, the elevated energetic and monetary costs relative to conventional thermal and pressure separation methods, such as reverse osmosis and distillation, significantly diminish the attractiveness of this endeavor. Recently, electrochemical methods are extending into the Li+ separation and extraction technologies, including electrodialysis and capacitive deionization. This work systematically reviews recent advancements in these electrochemical extraction methods for lithium concentration. First, it systematically assesses the key evaluation parameters including extraction capacity, selectivity factor, and specific energy consumption. Moreover, advanced characterization methods crucial for comprehending the intricacies of these electrochemical technologies are outlined. Specifically, this study elucidates the extraction principles of these electrochemical methods, consolidates the current state of advancement in these extraction techniques, and juxtaposes the performance parameters of these methods. Finally, it anticipates current challenges and delineates future research directions for lithium extraction via electrodialysis and capacitive deionization techniques, thereby furnishing guidelines for lithium extraction endeavors. [ABSTRACT FROM AUTHOR]

• CEM showed a greater advantage over AEM in improving coulombic efficiency. • Low charge efficiency was mainly attributed to co-ion repulsion. • A single IEM cannot effectively suppress co-ion repulsion. • The energy consumption and the desorption efficiency need to be a trade-off. Four different configurations of capacitive deionization (CDI) were assembled to comparatively investigate the contribution of different ion exchange membranes (IEMs), including anion exchange membrane (AEM) and cation exchange membrane (CEM), to the enhancement of desalination performance. The results showed that the low charge efficiency of membrane-free biochar-based CDI system was mainly attributed to co-ion repulsion rather than Faraday reactions, and a single IEM was not effective in suppressing the co-ion repulsion effect thereby exhibiting a similar low charge efficiency. Compared with AEM, CEM was more beneficial for high coulombic efficiency by restraining the oxygen reduction reactions. In addition, the electrosorption and desorption behaviors of the biochar-based membrane capacitive deionization (MCDI) under different operating conditions were explored. The results showed that zero voltage desorption (ZVD) was unfavorable to the desorption capacity of the electrode, especially in high concentration solutions, the reverse voltage desorption (RVD) led to higher desorption efficiency but required higher energy consumption. Therefore, energy consumption and regeneration efficiency need to be a trade-off in practical applications to realize energy saving and efficient desalination. [ABSTRACT FROM AUTHOR]

• MCDI pilot unit for treatment of brackish groundwater trialled in central Australia. • Two distinct electrode discharging strategies tested over the 1.5-year trial. • Negative potential discharging facilitated electrode regeneration. • Negative potential discharging enhanced monovalent over divalent ion selectivity. • Energy and economic efficiency of MCDI comparable to BWRO and EDR systems. A long-term field trial of membrane capacitive deionization (MCDI) was conducted in a remote community in the Northern Territory of Australia, with the aim of producing safe palatable drinking water from groundwater that contains high concentrations of salt and hardness ions and other contaminants. This trial lasted for 1.5 years, which, to our knowledge, is one of the longest reported studies of pilot-scale MCDI field trials. The 8-module MCDI pilot unit reduced salt concentration to below the Australian Drinking Water Guideline value of 600 mg/L total dissolved solids (TDS) concentration with a relatively high water recovery of 71.6 ± 8.7 %. During continuous constant current operation and electrode discharging at near zero volts, a rapid performance deterioration occurred that was primarily attributed to insufficient desorption of multivalent ions from the porous carbon electrodes. Performance could be temporarily recovered using chemical cleaning and modified operating procedures however these approaches could not fundamentally resolve the issue of insufficient electrode performance regeneration. Constant current discharging of the electrodes to a negative cell cut-off voltage was hence employed to enhance the stability and overall performance of the MCDI unit during the continuous operation. An increase in selectivity of monovalent ions over divalent ions was also attained by implementing negative voltage discharging. The energy consumption of an MCDI system with a capacity of 1000 m3/day was projected to be 0.40∼0.53 kWh/m3, which is comparable to the energy consumption of electrodialysis reversal (EDR) and brackish water reverse osmosis (BWRO) systems of the same capacity. The relatively low maintenance requirements of the MCDI system rendered it the most cost-efficient water treatment technology for deployment in remote locations. The LCOW of an MCDI system with a capacity of 1000 m3/day was projected to be AU$1.059/m3 and AU$1.146/m3 under two operational modes, respectively. Further investigation of particular water-energy trade-offs amongst MCDI performance metrics is required to facilitate broader application of this promising water treatment technology. [Display omitted] [ABSTRACT FROM AUTHOR]

The efficiency of saturated Activated Carbon (AC) electrochemical regeneration was evaluated. Reactor configurations in cathodic/anodic process, applied current effect on the properties of AC and Methylene Blue MB-AC interactions and adsorption/desorption mechanisms were studied. The efficiency was measured by adsorption capacity adsorption/regeneration cycles and changes in the adsorbent characteristic were analyzed through FTIR, BET, Optical Microscopy (OM) and SEM before and after the regeneration. The energy consumption was analyzed to assess the economic feasibility. It was found that the electrochemical treatment was efficient in returning the AC adsorption capacity, maximum efficiencies of approximately 79% and 84% were reached when the Carbon Fiber Cloth-AC electrode was subjected to anodic and cathodic currents, respectively, at a current of 0.1 A. In addition, the material demonstrated good stability through adsorption-regeneration cycles by cathodic process, with the material's adsorption capacity being almost totally recovered for 8 consecutive cycles. The removal percentage around 80% was kept after the cycles, with optimal conditions when the electrode was subjected to cathodic currents, NaCI as electrolyte at a current of 0.1 A for 2 h. The characterization techniques provided results that allow to explain the higher and prolonged efficiency of the cathodic current. Furthermore, these reactor configurations achieved an electrical energy consumption of 2.3 and 2.1 kWh kg-1 of material for cathodic and anodic, respectively. These results indicate that the electrochemical is an economical and environmental suitable technique capable of restore carbon adsorbents to be reusable for several water treatment cycles. [ABSTRACT FROM AUTHOR]

Lacquer wood (LW) goes through one-step and two-step H 3 PO 4 activation process to prepare activated carbons (ACs) at different temperature, and its performance was evaluated by testing CV, EIS, GCD and cycling respect to an electrode material in supercapacitors. The performance of lacquer wood activated carbon prepared by different activation methods and temperature (300, 400, 500, 600, 700, and 800 °C) was studied, and the influence on its electrochemical properties provides valuable guidance for the high-efficient energy utilization of lacquer wood. The results showed that the AC generated via one-step activation process at 400 °C demonstrate excellent specific surface area (S BET 1609.09 m2/g) than those from two-step activation method. Besides, the biomass-derived ACs presented overall better electrochemistry characteristic than those from charcoal-derived ACs. The largest specific capacitance (354 F/g) was obtained in the ACs-based electrodes which was generated from one-step activation process (activated at 600 °C). After 10000 cycles, its capacity retention reached 95.3%, which provides a meaningful guidance into the application of energy storage supercapacitors. This study proves that the LW derived ACs are promising electrodes of the high-performance supercapacitors, which is beneficial for value-added and industrial supercapacitors application of lacquer wood ACs. [Display omitted] [ABSTRACT FROM AUTHOR]

Undesired water crossover through ion‐exchange membranes is a significant limitation in electrically driven desalination processes. The effect of mitigating water crossover is twofold: 1) The desalination degree is less reduced due to the unwanted removal of water, and 2) the brine concentration is increased due to decreased dilution by an unwanted crossover of water molecules. Hence, water crossover limits the desalination and concentration efficiency of the processes, while the energy demand to achieve a certain level of desalination or concentration increases. This effect is especially pronounced when treating high salinity solutions, which goes hand in hand with the crossover of many ions through the ion‐exchange membranes. A crosslinked coating for cation‐exchange membranes (CEMs) is presented in this work, which can significantly mitigate such undesired water crossover. The efficacy is demonstrated using the flow‐electrode capacitive deionization process applied for desalination and concentration of saline brines at feed concentrations of 60 and 120 g L−1 NaCl. With just a single coated CEM, the water crossover was reduced by up to 54%. [ABSTRACT FROM AUTHOR]

Electrochemical advanced oxidation processes (EAOPs), based on the in situ generation of the powerful oxidant, hydroxyl radical (.OH), have been developed for effective destruction of recalcitrant organic pollutants. Electrode materials used both as anode and cathode constitute one of the key parameters affecting the process efficiency. The electro‐Fenton (EF) process is one of the most powerful EAOPs in water/wastewater treatment. Inversely to other EAOPs, in the EF process,.OH can be generated both in the bulk solution (from reagents formed at the cathode) and on anode surface. Therefore, the role of anode/cathode couple is of great importance for this process. This study focuses on the comparative performance of ten electrodes (5 anodes, 5 cathodes) through more than fifty combinations during removal of the antibiotic p‐aminosalicylic acid (p‐ASA), taken as target pollutant. The following parameters were chosen for performance assessment: oxidative degradation kinetics, the time needed for complete destruction of p‐ASA, mineralization rate, mineralization current efficiency and energy consumption. The results obtained highlight the following sequence for the performance of anodes: BDD > PbO2 > Ti4O7 > Pt≈DSA, and that of cathodes: carbon sponge ≥ carbon felt > graphite > stainless steel≈titanium. [ABSTRACT FROM AUTHOR]

Reverse Osmosis (RO) is one of the most advanced and effective membrane separation treatments in desalination. Forward Osmosis (FO) is also one type of membrane separation that can spontaneously draw the water from the RO concentrated water. However, the regeneration of draw solution requires much energy in the FO system. A Fertilizer-Drawn Forward Osmosis (FDFO) process is thus selected to reduce the energy consumption for the draw solution, where the fertilizer solution was used as the draw solution. The RO concentrated water is continuously concentrated, while the fertilizer draw solution is continuously diluted in the process of FDFO. The diluted fertilizer draw solution can widely be expected for the agricultural irrigation without regeneration. In this study, the influence factors of the forward water and reverse salt flux in the FO process were determined under the different type, concentration, and temperature of draw solution, as well as the concentration of feed solution. KCl, KNO3, NaNO3, NH4HCO3, (NH4)2SO4, and NH4Cl were selected as the draw solutions for the single factor comparison tests of FDFO. The results show that the forward water fluxes and reverse salt fluxes differed greatly with different kinds of draw solutions. The forward water fluxes of draw solutions were ranked in the order of KCl > NH4Cl > NaNO3 > NH4HCO3 > (NH4) 2SO4 > KNO3. The reverse salt flux was NaNO3 > NH4HCO3 > KNO3 > KCl > NH4Cl > (NH4)2SO4. The forward water flux of KCl and NH4Cl was the largest, while the reverse salt flux was smaller. Therefore, KCl and NH4Cl were more suitable for a single fertilizer draw solution. A FO test was carried out under the different concentration and temperature of KCl draw solution. The results showed that the forward water flux of KCl draw solution at 2 mol/L was 3.56 times than that of 0.5 mol/L, and the forward water flux of KCl draw solution at 55℃ was about twice than that of 25℃. Therefore, the forward water flux increased significantly, with the increase of the concentration and temperature of draw solution. However, there was no increase in the forward water flux and the reverse salt flux, when the concentration of draw solution increased exponentially. Additionally, the increased multiple of forward water and reverse salt flux was less than the draw solution concentration. Another FO test was also carried out under the various concentration and temperature of NaNO3 draw solution. The results showed that the reverse salt flux increased by 2.94 times, when the concentration of NaNO3 draw solution increased from 0.5 to 2 mol/L, while, the reverse salt flux increased by 1.64 times, when the temperature of NaNO3 draw solution increased from 25 to 55℃. Therefore, the reverse salt flux increased, with the increase of the concentration and temperature of draw solution. Furthermore, the temperature increased exponentially, so did the forward water flux. Since the RO concentrated and deionized water were selected as the feed solution in the FO experiment, it was found that the higher concentration of feed solution, but the smaller forward water flux. [ABSTRACT FROM AUTHOR]

With the development of industry, the large-scale consumption of fossil energy has brought serious environmental pollution. Therefore, the development of renewable clean energy to replace traditional fossil fuels has become the focus of research. In this study, nickel hydroxide (Ni(OH)2) composite was prepared by a simple hydrothermal method. Transmission electron microscope (TEM), scanning electron microscope (SEM) and X-ray diffraction (XRD) were used to characterize its morphology and structure. The results proved the successful preparation of the Ni(OH)2 composite and show that the prepared composite has a three-dimensional flower-like structure. In addition, the electrochemical performance of the prepared Ni(OH)2 composite was investigated under the three-electrode system. The three-dimensional flower-like structure of the composite can make the electrode and electrolyte fully contact, providing a rapid transfer path for ions and electrons to improve the electrochemical performance of the electrode material. This work provides new ideas for the preparation of self-assembled nickel-based materials and the wide application in electrocatalyst. [ABSTRACT FROM AUTHOR]

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The innovative design of collector is a top priority to drive the advancement of flow electrode capacitive deionization (FCDI) technology. Currently, the majority of FCDI research has concentrated on the implementation and modification of carbon-based flow electrode materials, while ignoring the effect of the current collector in FCDI. In this study, a 3D-FCDI configuration with porous titanium foam as the collector is designed, and rectorite (Rec) is used as the flow electrode in 3D-FCDI. Thanks to the porous structure of the 3D current collector, the collision opportunities of electrons with the Rec particles are increased and the long-distance migration of electrons in the conventional graphite collector is overcome, thus improving the system conductivity. The Rec exhibits good electrode dispersion, desalination rate, and energy consumption at low cost. In addition, the ASAR of Rec can be achieved by adjusting the electrode concentration (5 wt%), electrode flow rate (25 mL min−1) and operating voltage (1.8 V) to 11.43 μg cm−2 min−1. This study demonstrates the capability of 3D-FCDI configuration to advance the creation and implementation of FCDI. [Display omitted] • A 3D-FCDI configuration with porous titanium foam as the current collector is designed. • Collision opportunities of electrons and 3D-FCDI conductivity are increased. • Rectorite exhibits good desalination rate, and energy consumption at low cost. • 3D-FCDI is very conducive to the industrial application of FCDI technology. [ABSTRACT FROM AUTHOR]

Remarkable progress has been achieved to enhance the performance of electrochemical desalination technologies. Desalination batteries are promising due to their ability to simultaneously desalinate water and generate energy. A typical desalination battery consists of rechargeable high-capacity Na- and Cl-storage electrodes that remove ions during charging and release them during discharging. This technology works at low voltages and does not require chemicals, high-pressure pumps, or thermal heaters. Despite the existence of studies focusing on desalination batteries, a notable research gap persists regarding the assessment of performance characteristics, comparison of the various desalination battery designs, evaluation of energy consumption, and the exploration of the potential and limitations of desalination batteries. This highlights the need for a comprehensive review to address these key aspects. The goal of this work was to address these points by shedding light on the fundamentals, principles, and main findings related to desalination batteries to-date. Four main types of desalination batteries are surveyed: membrane-free, rocking chair, redox flow, and metal-air. Emphasis is given on energy considerations, as the energy consumption of desalination technologies has been a significant challenge for decades. Finally, research directions for further desalination battery developments are discussed related to both challenges and opportunities in the field. [Display omitted] • A critical review of desalination batteries • Comparative advantages of battery-based desalination over capacitive deionization • Comprehensive investigation of different desalination battery types • Energy consumption analysis in desalination batteries • Comparison of desalination batteries with state-of-the-art desalination technologies [ABSTRACT FROM AUTHOR]

• A concentrated real pharmaceutical wastewater was treated successfully with TOC removal at 87 %. • The system requires no chemical inputs other than catalytic amount of iron. • The system remained stable through 10 treatment cycles. • The regeneration of activated carbon was confirmed using various characterization methods. This study proposes a sustainable approach for hard-to-treat wastewater using sintered activated carbon (SAC) both as an adsorption filter and as an electrode, allowing its simultaneous electrochemical regeneration. SAC improves the activated carbon (AC) particle contact and thus the conductivity, while maintaining optimal liquid flow. The process removed 87 % of total organic carbon (TOC) from real high-load (initial TOC of 1625 mg/L) pharmaceutical wastewater (PWW), generated during the manufacturing of azithromycin, in 5 h, without external input of chemicals other than catalytic amounts of Fe(II). Kinetic modelling indicated that adsorption was the dominant process, while concomitant electrochemical degradation of complex organics first converted them to short-chain acids, followed by their full mineralization. In-situ electrochemical regeneration of SAC, taking place at the same time as the treatment, is a key feature of our process, enhancing its performance and ensuring its stable operation over time, while eliminating cleaning downtimes altogether. The energy consumption of this innovative process was remarkably low at 8.0×10−3 kWh g TOC −1. This study highlights the potential of SAC for treating hard-to-treat effluents by concurrent adsorption and mineralization of organics. [Display omitted] [ABSTRACT FROM AUTHOR]

[Display omitted] • The EDI device demonstrated excellent removal efficiency for high-concentration nutrient ions. • The ion migration in EDI device is mainly through the resin phase. • Adsorption and desorption rate of the resin are not the limiting conditions of ion migration in EDI. • The rate of ion migration is intricately influenced by the concentration of nutrient ions present on the resin. In this work, a constructed five-compartment electrodeionization (EDI) device was used to treat simulated wastewater with ammonium and phosphate ions. The voltage and influent concentration in the EDI system were examined. Meanwhile, the ion migration characteristics in the EDI were studied. Results showed that at optimal conditions, operating at 15 V, with an ammonia nitrogen concentration of 1500 mg/L, and a phosphate concentration of 300 mg/L, the removal rates of ammonia nitrogen and phosphate were 98.50 % and 73.85 %, respectively. The energy consumption of ammonia and phosphorus was 1.347 kWh/mol and 43.629 kWh/mol. The ion migration characteristic experiments revealed that adsorption and desorption rates of the resin do not impose limitations on ion migration in EDI; the ion migration in EDI device is mainly through the resin phase and the rate of ion migration is intricately influenced by the concentration of nutrient ions present on the resin. [ABSTRACT FROM AUTHOR]

• Natural organic mater and major ions challenge AOPs efficiency in realistic waters. • Electrodialysis (ED) enables to separate interfering substances from micropollutants. • Combining ED pretreatment and AOP enhances micropollutants degradation. • Addition of ED pretreatment reduced overall energy demand of VUV-AOP treatment. Advanced oxidation processes (AOPs) augment traditional water treatment methods, enhancing the removal of persistent contaminants. Efficiency of AOPs that utilize UV radiation for oxidants generation (e.g., ·OH) is reduced in water matrices that contain substants that may act as inner UV filters and/or scavengers for the generated radicals. Among such interfering compounds are major inorganic ions and dissolved organic matter that are naturally present in realistic waters. Thus, to improve AOPs efficiency it is desirable to separate the target pollutants from these natural species before treatment. Here the potential of electrodialysis as such pretreatment was investigated. The impact of this pretreatment on photo-oxidation of the pharmaceutical carbamazepine (CBZ) under VUV (λ<200 nm) irradiation, which yields ·OH generation via water homolysis, was tested in different water matrices. The obtained results indicate that in all tested solutions: Deionized water, groundwater, surface water, and treated wastewater, the addition of electrodialysis pretreatment successfully separated the target micropollutant CBZ from the major natural ions and to some extend the NOM, resulting faster degradation rates of CBZ and its transformation products in the following VUV-based AOP. Energy cost calculations indicated that addition of this pretreatment step reduces the overall energy demand of the system (i.e., energy consumption for the electrodialysis step was smaller than the energy gained by reducing the required VUV irradiation dose). [Display omitted] [ABSTRACT FROM AUTHOR]

The requirement for materials possessing both high strength and low density has garnered significant attention from industries and researchers in recent times. Among these materials, aluminum 6061 (Al6061) exhibits the desired properties. However, due to its diverse machining capabilities, powder-mixed electric discharge machining (PMEDM) has emerged as a viable option for cutting such materials. This method has been criticized for its high energy consumption and limited cutting efficiency. Furthermore, conventional dielectric (kerosene) employed in EDM has drastic environmental and operator's health concerns. To address the abovementioned issues, deionized water has been employed in this study which enhances the reusability of resources and minimizes the cost of the dielectric. Herein, to make the process sustainable, and to keep the environment free from hazardous fumes, generated during the machining process, deionized water has been used. In addition to that, to uplift the machining responses, alumina (Al 2 O 3) nano-powder has been engaged. To conduct the study, response surface methodology (RSM) was employed. This investigation aimed to analyze the impact on the material removal rate (MRR), surface roughness (SR), and specific energy consumption (SEC) by using microscopy analysis, scanning electron microscopy (SEM), 3D surfaces profilometry, energy dispersive x-ray (EDX) analysis and after that, the machining responses are modelled using the artificial neural networks (ANN) technique. It was observed that by utilizing non-dominated sorting genetic algorithms (NSGA-II) an improvement of 87.42 % in MRR, 3.4 % better surface finish and 0.7 % better SEC have been obtained. Notably, CO 2 emissions were found to be 94.27 % lower by using the deionized water as dielectric compared to those produced by kerosene oil. [ABSTRACT FROM AUTHOR]

Recirculation of hydrothermal carbonization (HTC) process water (PW) has been revealed as an effective strategy to promote the recovery of lost dissolved organics in the spent solvent. However, the role of operating parameters such as temperature, time and solid load during recirculation needs to be clarified and better investigated in order to achieve a successful PW valorization. In this paper, the effects of different reaction conditions during HTC with PW recirculation were studied by using orange peel waste as feedstock. The results showed that strong synergistic interactions occurred between the biomass and the recycled solvent, leading to a hydrochar mass yield increase between 0.5 and 11 wt% on a dry basis (d.b.), according to the reaction conditions. PW recirculation, especially at low conversion severity and solid load, increased hydrochar carbon content while drastically reduced the oxygen fraction. The reason was probably related to promoted dehydration and decarboxylation. As result, carbon and energy yields were respectively increased by 26.1 % and 27.0 %, on average. The energy balance outcomes showed that the energy recovery rose up to 8 times by recycling PW compared to phases with deionized water as HTC solvent. [Display omitted] • Hydrochar recovery enhancement is obtained by solvent recirculation. • Intense synergistic effects in hydrochar formation occur at low temperatures. • Dehydration and decarboxylation are promoted by solvent recycling. • Hydrochar carbon retention is increased by 6.2 % after recirculation at 180 °C. • Process water recirculation improves the conversion energy efficiency. [ABSTRACT FROM AUTHOR]

[Display omitted] • Mn dopant-reinforced NaTi 2 (PO 4) 3 possesses superior structural stability and conductivity. • The optimal NT 1.5 M 0.5 P exhibits ultrahigh salt removal capacity of 128.5 mg/g and cycle stability. • The ultrahigh durability is rooted from the solid-solution reaction induced by Mn-ions pillar. • NT 1.5 M 0.5 P||NaFeHCF rocking-chair desalination battery owns stable, rapid and low energy consumption desalination. Battery deionization (BDI) technique has attracted great attention as a potential candidate to tackle the freshwater crisis, but its application is plagued by the lack of electrode materials with large desalination capacity and excellent durability. Herein, Mn dopant-reinforced NaTi 2 (PO 4) 3 (NT 2–x M x P) composites with significantly enhanced structural stability and electronic/ionic conductivity were fabricated toward seawater desalination. Especially, the NT 1.5 M 0.5 P exhibits excellent desalination performance, affording a salt removal capacity (SRC) of 128.5 mg/g with a salt removal rate (SRR) of 18.4 mg g−1 min−1 and almost no capacity attenuation after 500 cycles. Furthermore, the NT 1.5 M 0.5 P further possesses favorable technical feasibility in different aqueous media, including desalination at various NaCl concentrations, temperature, solution pH, and natural seawater. Mechanism studies reveal that the NT 1.5 M 0.5 P undergoes a solid-solution reaction based on the reversible electrochemical reaction of the Ti4+/Ti3+ redox pair during the desalination/salination process. A rocking-chair desalination battery consisting of NT 1.5 M 0.5 P and NaFeHCF demonstrates a favorable desalination ability (average SRC of 49.4 mg/g and SRR of 1.73 mg g−1 min−1), outstanding cycling stability (92 % of capacity retention in 100 cycles), low energy consumption (0.288 kWh/kg-NaCl) and high average charging efficiency (86.9 %). This work sheds light on the rational design of advanced NASICON-type electrodes for seawater desalination with remarkable desalination capacity and long serving life. [ABSTRACT FROM AUTHOR]

Membrane capacitive deionization (MCDI) is a unique electrochemical separations platform that allows for energy recovery during electrode regeneration. Similar to other electrochemical separation technologies producing deionized water (e.g. electrodialysis), ohmic resistances in the spacer channel significantly hampers the performance and energy efficiency of the process. This work devised a series of ionomer coated nylon mesh nets to address spacer channel resistances in MCDI. Under constant current operation, the ionomer coated nylon meshes displayed a 300 mV lower cell voltage rise during deionization while sustaining the same deionization rate. Furthermore, energy recovery was improved by 1.4x to 5.5x depending on the saline feed concentration. The lower cell voltage rise during deionization combined with the greater energy recovery with ionomer coated meshes resulted in energy normalized adsorbed salt (ENAS) values that were 2x to 3x greater. Addressing the spacer channel resistances in MCDI allowed for 8% to 19% increase in current density without the cell voltage exceeding 1.6 V—the upper bound set for mitigating parasitic reactions. Operating at higher current density leads to smaller MCDI units for a given deionization requirement and has implications for reducing the capital costs of the MCDI unit. [ABSTRACT FROM AUTHOR]

The capacitive deionization of water (CDW) was investigated with the purpose to obtain pure water. To this end, mosaic cation–anion-exchange membranes and activated carbon electrodes were used. The mosaic membranes contained cation- and anion-exchange components embedded in a synthetic-fiber-based matrix. The means of preparation for the pressed mosaic membranes included pressing the cation- and anion-exchange membranes into each other. Another method was via the subsequent formation of cation- and anion-exchange bands in the fibrous matrix (in a banded membrane). The activated carbon electrodes and mosaic membranes possessed sufficient specific ion surface conductivities even in clean water. The specific energy consumption was 31.9 and 111.7 W mol–1 for the CDW devices containing banded and pressed membranes, respectively. Therefore, the banded membrane was preferable for obtaining pure drinking water. It was found that the CDW with the banded mosaic membrane exhibited the best performance at a voltage of 2 V and a solution flow rate of 15 cm3/min. [ABSTRACT FROM AUTHOR]

To survive, organizations should inevitably work based on sustainability principles in an ever-increasing changes of markets. Appropriate flexibility and responsiveness are particularly important when considering sustainability issue and market changes in clustering problem. One of the uses of clustering can be allocation of resources and equipment for providing the highest level of customer service which has been a matter of concern for decision makers in distributive companies. Capacitive clustering is a common method for solving allocation and distribution problems. However, traditional clustering models ignore sustainability criteria in defining clusters' capacity. The objective of this study, therefore, is to propose a novel method for optimizing resource allocation for customers given the sustainability criteria. Capacitive clustering is a technique that has a widespread application in data mining. This approach has been used for equipment distribution, sales targeting, market segmentation, etc. One prevalent clustering method is growing neural gas network (GNGN) technique. GNGN is a neural network with uncontrolled learning. In this paper, for the first time, we utilize GNGN to cluster customers given sustainability criteria. Here, the clusters' centers are determined and allocated with regard to capacity constraints of the clusters. The obtained results in general can be regarded as an optimized sustainable distribution system in which the number of trucks, distribution routes as well as fuel consumptions and environmental pollutions are minimized. We can also refer to reductions in urban traffic, maintenance costs, staff costs, and decreases in the fatigue of drivers and distributers due to the proximity of supermarkets. An illustrative case study is done to indicate the applicability and remarkable contributions of the suggested clustering approach. [ABSTRACT FROM AUTHOR]

An emerging class of electrochemical systems utilize redox-active chemicals as input to simultaneously desalinate water and produce electricity within a single cell. This contrasts with traditional desalination technologies, such as reverse osmosis, electrodialysis and capacitive deionization, which consume net electricity during desalination. The underlying reason is that traditional desalination technologies perform solely a separation process, while such chemical-energy driven systems perform a combined process consisting of a spontaneous chemical reaction and a separation. Thermodynamic energy efficiency (TEE) of traditional technologies is defined as the ratio of the minimum energy to drive the separation process reversibly to the energy needed to perform the separation in practice. However, such a definition is not appropriate for systems which co-generate electricity and desalinated water. We propose that for these latter systems, TEE should be defined as the device electricity output divided by the maximum available energy. We develop a theoretical framework predicting the maximum available energy yielded by a combined redox reaction-desalination process. We utilize our framework to explore various input redox chemistries, and predict a maximum energy output of up to ∼25.74 kWh per m3 of desalinated seawater. We further introduce and experimentally characterize a desalination fuel cell driven by a hydrogen-oxygen redox couple, and apply our model to provide a first-time quantification of its TEE. [ABSTRACT FROM AUTHOR]

In this paper, the effects of using carbon-based nanofillers/water nanofluids as a coolant fluid in a photovoltaic thermal system from both energy and exergy viewpoints are experimentally presented. The considered nanoparticles including MWCNTs, SWCNTs, and GNPs are dispersed in deionized water as the base fluid by 0.05 mass%. The experiments are carried out on certain days in August and September at Ferdowsi University of Mashhad, Mashhad, Iran. In order to investigate the consistency of the results, an uncertainty of the experiments is examined. The various mass flow rates are investigated in all cases, and as a result, an optimum mass flow rate of 50 kg h−1 based on first and second laws of thermodynamics is selected. According to the results, employing GNP/water, SWCNT/water, and MWCNT/water increase the total average overall energy efficiency by 19.3%, 15.24%, and 9.46% in comparison with pure water, respectively. Additionally, GNP/water, SWCNT/water, and MWCNT/water reduce the total average entropy generation of the module by 2.88%, 1.23%, and 0.82% compared to the pure water, respectively. It has been found that implementation of GNP/water nanofluid leads to more improvement in the module performance among other coolant fluids. [ABSTRACT FROM AUTHOR]

A low consumption and facile method was employed to prepare hollow nickel–cobalt-layered double hydroxide (NiCo-LDH) nanoflakes grown in situ on nickel foam in deionized water at room temperature. By using MOFs (Metal–organic frameworks) as the precursor and then adjusting the Ni2+ ion exchange reaction time, the surface morphology and electrochemical performance of NiCo-LDH electrode materials can be greatly optimized. NiCo-LDH nanoflakes with a thickness of 150 nm as electrode material have a high specific capacity of 2148 F/g at the current density of 1 A/g and possess cycling stability of 82% capacity retention after 1000 cycles. This study provides a prominent approach for fabricating hollow nanomaterials with three-dimensional structures, and its excellent electrochemical performances make it a promising candidate for low energy consumption and high-performance energy storage devices. [ABSTRACT FROM AUTHOR]

Aniline was synthesized from nitrobenzene through photo‐induced reduction in microreactors under UV irradiation. Nitrobenzene solution and the nanofluid prepared by a TiO2 nanocatalyst, PEG‐400, and deionized water were mixed in a capillary microreactor. The effects of catalyst composition, residence time, and substrate concentration on the reaction performance were systematically investigated. The conversion of nitrobenzene and the yield of aniline reached high values under optimized conditions. The excellent reusability of the photocatalyst was realized for four runs. A mechanism was proposed for this photocatalytic reduction process based on reaction kinetics. Both photo‐induced electrons and •CO2− could reduce nitrobenzene to aniline. The photonic efficiency in the microreactor was still much higher than that obtained in batch reactors, which was mainly attributed to the much larger effective radiation area of the microreactor. [ABSTRACT FROM AUTHOR]

Faradaic deionization (FDI) has been proposed as an effective solution to the desalination. However, developing a cathode material that possesses high desalination efficiency, lower energy consumption and good stability remains a significant challenge. Herein, we prepared urchin-like AlV 3 O 9 (AlVO) microsphere with different crystal structure using hydrothermal process followed calcination as cathode material for capacitive deionization. Among them, lamellar AlVO-350 with interlayer crystalline waters of the hydroxide group exhibit a desalination capacity of 92.97 mg g−1 and notably a better cycling stability due to the synergistic effect of coordinated water charge shielding and hydrogen bonds stabilities on layered structure. On the other hand, the AlVO-550,which has a higher ratio of V5+/V4+, provided a desalination capacity of 101.70 mg g−1. It achieves a charging efficiency of 88.6% and an energy consumption of 0.329 kWh kg−1, which attributed to the high proportion of V5+ in VO slabs, facilitating Na+ intercalated reactions. This work opens up pavement for designing more advanced electrode materials for FDI. • Urchins-like aluminum vanadate microspheres were synthesized by combining hydrothermal with subsequent calcination method. • Aluminum vanadate electrode with crystalline waters and higher ratio of V5+/V4+ exhibits enhanced desalination properties. • The ex-situ XRD and XPS show that the reversible Na+ intercalation mechanism of aluminum vanadate electrode. [ABSTRACT FROM AUTHOR]

The capacitive deionization (CDI) technology for the removal of U(VI) has been the focus of attention because of its superiorities in operation cost, energy consumption, and environmental friendliness. In this report, electrode materials based on sulfonic acid‑decorated FeOOH were applied to CDI and flow electrode capacitive deionization (FCDI) for the first time. The sulfonic acid‑decorated FeOOH nanorods presented a high electrosorption capability of U(VI) in the CDI system (709.4 mg g−1 at 1.2 V and pH = 4.0, based on Langmuir model), which may result from the coordinative surfaces as well as the mesoporous structures of FeOOH. The thermodynamic and kinetic behaviors of the electrosorption process can be well-fitted using the Freundlich and pseudo-second-order model. The effective electrosorption in the presence of Na+ competitive ions and recycling of adsorbents in the CDI system further demonstrated the potential application of sulfonic acid‑decorated FeOOH nanorods for the electrosorptive removal of U(VI) from radioactive wastewater. The electrosorption mechanism was determined to be a combined process that is composed of diffusion of the uranyl ions into the EDL and adsorption onto the surface of FeOOH via the coordination interaction from Fe-OH and sulfonic acid groups (-SO 3 H). Further, continuous FCDI batch experiments in low concentration of feed water (60 mg L− 1 U) show that removal efficiency of U remained over 99% in 10 times continuous cycles, endowing it more possibilities for capacitive deionization from research to practical application. [Display omitted] • Sulfonic acid‑decorated FeOOH were firstly applied to CDI and FCDI. • This sulfonic acid‑decorated FeOOH affords remarkable performance for capture of U (VI). • Adsorption mechanism is mainly the synergistic effect of coordinative surfaces as well as the mesoporous structures. [ABSTRACT FROM AUTHOR]

[Display omitted] • Bph and hBN improve the ability of RGO sponges to store electrical charge. • Consistent high removal of contaminants in continuous and intermittent current. • Shorter OFF cycles were more effective in producing oxidizing species. • Energy consumption was reduced 2-fold using intermittent current. • Ions in the wastewater impacted positively the Bph and hBN-RGO anode performance. Borophene (Bph) and hexagonal boron nitride (hBN)-modified graphene sponge anode coupled to N-doped graphene sponge cathode were applied for electrochemical degradation of persistent organic contaminants using intermittent current. Three different ON-OFF pulse cycles were tested using low-conductivity supporting electrolyte in flow-through mode. Functionalization of the reduced graphene oxide (RGO) with Bph and hBN improved the ability of the double layer to store electrical charge, thus maintaining the generation of H 2 O 2 , O 3 , and ·OH even during the OFF cycles. Both anodes tested showed enhanced contaminant removal during shorter OFF periods (e.g. 52.5 s/52.s and 75 s/30 s ON/OFF), due to the improved retention of anode charge during the shorter OFF stages. Electrochemical removal of the target contaminants required 24 kWh m−3 in continuous current mode for both hBN-RGO and Bph-RGO anodes at 231 A/m−2, which was lowered to 11.7 and 13.5 kWh m−3 respectively, using ON-OFF pulse cycles. Electrochemical degradation pathways were elucidated in both systems using carbamazepine as a representative persistent contaminant. Flow-through reactors with both Bph- and hBN-RGO anodes removed ≥60 % of the target contaminants in a single pass using continuous current, whereas intermittent current led to somewhat decreased removal efficiencies (43–58 %) due to the scavenging effect of the wastewater matrix. Thus, halving the current ON time led to less than 20 % decrease in the removal efficiencies due to the capacitive properties of RGO. Given that switching to intermittent current decreased the energy consumption from 9.3 kWh m−3 to 4.4 kWh m−3 (Bph-RGO anode) and from 6.9 kWh m−3 to 3.6 kWh m−3 (hBN-RGO anode), higher removal of the target contaminants can be achieved by coupling sequential reactors in the intermittent current mode. [ABSTRACT FROM AUTHOR]

• A comprehensive review of electro-driven technologies for phosphorus enrichment was provided. • Enrichment rate and energy consumption were important indicators for phosphorus enrichment. • Phosphorus enrichment promoted p recovery efficiency and vivianite formation. • Prospect and directions of electro-driven technologies for phosphorus enrichment and recovery were presented. The recovery of phosphorus from wastewater is a critical step in addressing the scarcity of phosphorus resources. Electro-driven technologies for phosphorus enrichment have gathered significant attention due to their inherent advantages, such as mild operating conditions, absence of secondary pollution, and potential integration with other technologies. This study presents a comprehensive review of recent advancements in the field of phosphorus enrichment, with a specific focus on capacitive deionization and electrodialysis technologies. It highlights the underlying principles and effectiveness of electro-driven techniques for phosphorus enrichment while systematically comparing energy consumption, enrichment rate, and concentration factor among different technologies. Furthermore, the study provides a thorough analysis of the capacity of various technologies to selectively enrich phosphorus and proposes several methods and strategies to enhance selectivity. These insights offer valuable guidance for advancing the future development of electrochemical techniques with enhanced efficiency and effectiveness in phosphorus enrichment from wastewater. [ABSTRACT FROM AUTHOR]

• Membrane capacitive deionization (MCDI) can be used to separate permanently charged organic cations or anions such as ionic liquids that can differ greatly in polarity and size. • The separation efficiency depends on the symmetry of mobility of the respective anion and cation. • Supports the suitability of MCDI for pollutant removal from (waste)water. Persistent and mobile organic chemicals are a growing concern for the management of water resources. Here, we propose membrane capacitive deionization (MCDI) for effective separation and selective recovery of these chemicals. Using a simple MCDI process, with activated-carbon-cloth electrodes, we experimentally demonstrate the feasibility of MCDI for adsorbing permanently charged ionic liquids (ILs) and ionogenic chemicals (IOCs) such as perfluorooctanoic acid (PFOA) and diclofenac. The total salt adsorption capacity (SAC) of ILs and IOCs is between 5.12 and 8.83 µmol/g and is strongly dependent on the symmetry of cation and anion mobilities, as represented by their diffusion coefficients. The system has a low energy consumption of 0.031 kWh/m3, with a productivity of 83.33 L/h/m2. As an example of pharmaceuticals in wastewater we examined diclofenac solution and show a total SAC of 3.03 µmol/g. These results demonstrate the potential of this deionization process for the cleanup of industrial or medical wastewater. [ABSTRACT FROM AUTHOR]