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Abstract: Climate change and the increase of population pose challenges to ensuring suitable water supply in water-scarce regions. This work presents a comparative analysis of the water-supply approaches adopted in Los Angeles, Southeastern Spain, and Sydney. Results show a decrease in per-capita water use in the period 2000–2020, which reflects an improvement in water conservation. Social factors in the domain of hydropolitics and economic efficiency explain the divergence of water policies adopted. The adaptation to water scarcity and growing population in three regions of developed countries located in different continents sheds light on challenges facing the achievement of water security worldwide.

Hybrid membranes combining graphene oxide (GO) and silicon dioxide (SiO 2) were successfully developed for pervaporation desalination using porous zircon tube substrates. These GO/SiO 2 membranes were carefully designed by adjusting the amount of GO and the pH levels during the dip-coating process on the zircon tube surface. The study aimed to investigate how varying amounts of GO and pH levels affect the membranes' properties and desalination performance. The results indicate that raising the pH level decreases the membranes' hydrophilicity and enhances their stability. Conversely, increasing the amount of GO increases the membranes' hydrophilicity and reduces their pore size. Higher pH levels and GO amounts resulted in better salt rejection but lower water flux. Among the tested membranes, GS-6 (0.3 % GO/SiO 2 , pH 6) achieved the highest salt rejection rate of 99.96 % at 30 °C with a 1 % NaCl feed concentration. In contrast, GS-1 (0.1 % GO/SiO 2 , pH 4) showed the highest water flux of 8.54 kg m−2 h−1 at 60 °C with the same feed concentration. Increasing the temperature led to decreased salt rejection but increased water flux. Additionally, higher feed concentrations lowered both salt rejection and water flux. [ABSTRACT FROM AUTHOR]

Chitosan nanosheets (NS) stabilized on poly (3,4-ethylenedioxythiophene): poly(styrene sulfonate) (PEDOT: PSS) was functionalized using Fe3O4 to capacitively remove chloride ions and toxic cadmium ions at optimized pH, concentration, and number of charging cycles. The synthesis procedure was investigated by Fourier transform infrared spectroscopy (FTIR), X-Ray Diffractometer (XRD), Transmission Electron Microscope (TEM), Scanning Electron Microscope – Energy Dispersive X-ray Spectroscopy (SEM-EDS), and Brunauer-Emmett-Teller (BET). The analyses confirms increase in surface area of the nanocomposite from 41 to 132 m2/g and a decrease in crystallinity from 75.3 to 66.9% after nanosheet formation. The highest sorption exchange capacity (SEC) for this work, 93% CdCO3 removal is achieved at 100 CDI cycles while 82% NaCl removal was achieved at 80 cycles. The SEC% increased with pH during Na ion deionization and decreased with pH during Cd removal. The works shows that chitosan is able to impart advanced structural properties to Fe3O4 and PEDOT and is able to reduce reverse migration of ions from electrodes to bulk solution, leading to higher SEC performance. [ABSTRACT FROM AUTHOR]

Fabrics consisting of cotton‐core/polypyrrole (PPy)‐sheath fibers (cotton/PPy fabrics) are synthesized by aqueous chemical oxidative seeded polymerization of pyrrole and are utilized as a solar evaporation device. Scanning electron microscopy studies and elemental microanalyses reveal the thickness of the PPy sheath increases from a few tens nm to ≈200 nm with an increase of pyrrole monomer concentration in the polymerization system. The temperature of cotton/PPy fabrics increases upon irradiation with artificial sunlight to ≈33–45 °C in the dry state, due to light‐to‐heat photothermal conversion by the PPy component. Thanks to the photothermal property of the fabrics, water impregnated within the cotton/PPy fabrics can evaporate efficiently under the irradiation of artificial sunlight. Light‐induced water evaporation experiment using an artificial seawater confirms that ionic concentrations drastically decreases, indicating successful desalination. [ABSTRACT FROM AUTHOR]

The cement industry is a widely used and energy-consuming sector, making it one of the largest CO 2 emitters, primarily to meet its energy demands. Therefore, this research aims to evaluate the waste heat recovery process from a cement factory to fulfill a portion of its energy requirements. In this study, four scenarios have been evaluated, including power production scenarios, hydrogen production scenarios, methanation production process evaluation scenarios, blending hydrogen with natural gas, oxy-fuel combustion scenarios, and scenarios for producing the required freshwater for the factory and the water electrolysis process. The results show that the steam Rankine cycle with the reheating process and the organic Rankine cycle with methanol working fluid with a production capacity of 24.35 MW, and a payback period of 2.4 years with levelized cost of energy being 0.005809 $/kWh, is the most favorable scenario for the power generation cycle. Also, the process of alkaline electrolysis with a hydrogen production rate of 0.1648 kg/s, and a payback period of 5.816 years, and also with the levelized cost of hydrogen being 1.001 $/kg, happened to be the most suitable hydrogen production scenario compared to other electrolysis scenarios such as PEM and SOEC. Moreover, the process of water desalination by reverse osmosis with the energy consumption of 2.7 MW of power is capable of supplying all the required water of the factory and the water electrolysis process, and it was determined as the most suitable scenario for supplying the required water. • 4E analyses of four power generation scenarios is performed for WHR in cement plants. • Comparing power generation scenarios shows RC with reheating as the most favorable. • Alkaline electrolysis emerges as the top scenario for hydrogen production. • ORC systems with reheating show energy and economic advantages despite lower power. • Reheating in steam RC yields highest power production and economic viability. [ABSTRACT FROM AUTHOR]

This research investigates a sustainable and renewable mobile energy system designed for electricity production, hydrogen generation, and seawater desalination. It targets critical energy and freshwater needs during disaster scenarios, particularly in island nations and coastal cities where infrastructure may be compromised. The system integrates advanced technologies, including wind turbines, photovoltaic panels, solar collectors, and reverse osmosis units, all mounted on a green ship. Simulations using Engineering Equation Solver software indicate that in July, the system can produce 2,201,865 MJ of electricity, 7252 kg of hydrogen, and 3456 tons of fresh and hot water. This output can power 1072 electric vehicles and 1284 hydrogen-powered vehicles while supplying cold water to 57,600 people and hot water to 5760 people. By relying on renewable energy, the system prevents approximately 43,543 kg of carbon emissions in July. The total monthly economic value is estimated at $47,241.36, demonstrating its potential as a sustainable solution for disaster response and coastal communities. [Display omitted] • Hydrogen generation of the combined hybrid renewable system. • Thermodynamic efficiencies of components and overall the system for a green ship. • The comparison of the power generation of the wind turbine, Organic Rankine Cycle, and solar cell. • The monthly carbon saving quantity of the renewable hybrid system. [ABSTRACT FROM AUTHOR]

Five clay poultices used in built heritage, stone, and wall painting conservation were examined for their potential to extract impurities from medieval lime-rich wall painting plaster. Since the most efficient extraction is achieved by capillary advection, this evaluation compared the pore size distribution of the clay poultices with that of medieval plaster. The pore size distribution was measured using the pressure plate method, a method with a long history of use in soil and building science. The present study demonstrates for the first time a successful application of this method in the evaluation of clay poultices for conservation. In addition, the retentive capacities of the five poultices were examined by measuring lateral migration and penetration depths as a function of time, using customised plaster samples and a blue dye to facilitate migration measurements. Of the five poultices, bentonite showed the least promising pore size range and was estimated to have little or no effect as a drying poultice for medieval wall painting plaster. The remaining four poultices showed promising results, although with various shortcomings that might influence the results of the intervention, as the best fit is dependent on the aim of the poulticing. For a cleaning poultice, where dirt is to be extracted solely from the surface of the plaster, attapulgite and PANGEL® S1500 seemed to be best suited due to their high retention. The pore size distribution and migration pattern of PANGEL® S9 and sepiolite indicated that they could be suitable as poultices for desalination. [ABSTRACT FROM AUTHOR]

The conventional packed bed humidifiers encounter significant drawbacks such as scale formation, spray nozzle clogging, corrosion, and relatively poor effectiveness, which adversely affect their reliability and lifespan, thereby escalating their operational and capital costs. To tackle these issues, bubble column humidifiers have been proposed. The bubble column design ensures maximum air–water interaction, enhancing component effectiveness, while obviating the need for atomizers, thereby decreasing maintenance expenses, and enhancing heat and mass transfer efficiency. Moreover, studies related to a moving streams multi-stage bubble column HDH design are lacking. Therefore, this study aims to provide a theoretical analysis of various configurations of multi-stage moving streams bubble column humidifiers, aiming to bridge the performance knowledge gap between moving stream and nonmoving stream bubble column humidifiers. A mathematical model based on heat and mass transfer was developed and validated against published data. The effect of multistaging, water inlet temperature, air inlet temperature, and inlet relative humidity on the total effectiveness, outlet humidity ratio and outlet air temperature are studied. Results reveal that multistaging is effective in boosting the maximum effectiveness of single stage bubble column humidifier from 27% and 33% to about 94% and 94%, for the parallel and series configurations, respectively. Furthermore, both series and parallel configurations show similar performance with a slightly higher performance for the series arrangement. Additionally, this study discusses the operational and maintenance differences between the parallel and series multi-stage bubble column humidifiers, with the series configuration having a more straightforward operation compared to the parallel arrangement. However, the parallel configuration requires less complicated maintenance in comparison to the series multi-stage configuration. The outcomes of this study are pivotal to understanding the optimum operating conditions of the humidifier for its possible integration with the dehumidifier. Consequently, an improved humidification dehumidification (HDH) desalination system can be attained. [ABSTRACT FROM AUTHOR]

The flake biochar electrode materials with fast ion transport function were prepared by KOH activation walnut shell used as raw material. The effects of carbonization temperature and KOH-to-biochar ratio were systematically evaluated using physicochemical characterization and electrochemical performance testing. The optimized walnut shell biochar (WSC800–2), produced at 800 °C with a KOH-to-biochar ration of 2:1, exhibited an exceptional specific surface area (2,287 m2 g−1), the highest porosity (0.824 cm3 g−1), and an excellent specific capacitance (369.51 F g−1, 10 mV s−1). Furthermore, in desalination experiments, WSC800–2 achieved a high salt adsorption capacity of 15.70 mg g−1 at 1.2 V, 500 mg l−1 NaCl solution. The electrode also exhibited outstanding cycling stability, retaining 97.0% of its performance after 10 adsorption/desorption cycles. These findings highlight the potential of walnut shell-derived biochar as an effective material for capacitive deionization and future desalination technologies. [ABSTRACT FROM AUTHOR]

The article discusses the global water crisis and the role of membrane technology, particularly reverse osmosis (RO), microfiltration (MF), and ultrafiltration (UF), in addressing water challenges by 2050. Membrane technology has evolved to provide safe, sustainable drinking water by treating unconventional water sources like seawater, brackish groundwater, and wastewater. The article highlights the advancements in RO membranes for desalination, the importance of MF and UF membranes for pathogen treatment, and the potential of other membrane technologies like electrodialysis (ED) and membrane distillation (MD) in water treatment by 2050. [Extracted from the article]

The increase in demand for water has caused attention to non-traditional methods for water supply in many places. Solar still is a simple, economical and suitable technology for providing drinking water from salt water that can be used even in remote areas. The challenge facing these technologies is to increase their performance, which is possible through three ways: environmental, design and operational parameters. This research has investigated the potential and location of Iran for the installation of solar still using environmental parameters. The three parameters of ambient temperature, solar radiation intensity and wind velocity are the most important environmental parameters affecting the performance of solar still; hence, they were used to investigate the potential of Iran to install solar still. The long-term information of the desired environmental parameters was prepared using field and telemetry methods; then, by averaging each parameter in ArcGIS software, a map was prepared for the ease of analysis and review. The results show that Iran has a high potential for using solar still in terms of environmental conditions affecting the performance of solar still and having brackish water resources and the provinces of Sistan and Baluchistan, Hormozgan, Fars, Kerman and Bushehr are the most favorable places in the country. Iran has been investigated for the installation of solar still based on three parameters. Also, the results show that the provinces of Sistan and Baluchistan (2196 kWh/m2), Fars (2148 kWh/m2), Hormozgan (2136 kWh/m2), Kerman (2116 kWh/m2), and Kohkiloyeh and Boyer-Ahmad (2098 kWh/m2), are the regions with highest potentials for installation of solar based water desalination systems in Iran. [ABSTRACT FROM AUTHOR]

Interfacial solar-driven evaporation technology shows great potential in the field of industrial seawater desalination, and the development of efficient and low-cost evaporation materials is key to achieving large-scale applications. Hydrogels are considered to be promising candidates; however, conventional hydrogel-based interfacial solar evaporators have difficulty in simultaneously meeting multiple requirements, including a high evaporation rate, salt resistance, and good mechanical properties. In this study, a Janus sponge-like hydrogel solar evaporator (CPAS) with excellent comprehensive performance was successfully constructed. The introduction of biomass agar (AG) into the polyvinyl alcohol (PVA) hydrogel backbone reduced the enthalpy of water evaporation, optimized the pore structure, and improved the mechanical properties. Meanwhile, by introducing hydrophobic fumed nano-silica aerogel (SA) and a synergistic foaming-crosslinking process, the hydrogel spontaneously formed a Janus structure with a hydrophobic surface and hydrophilic bottom properties. Based on the reduction of the evaporation enthalpy and the modulation of the pore structure, the CPAS evaporation rate reached 3.56 kg m-2 h-1 under one sun illumination. Most importantly, owing to the hydrophobic top surface and 3D-interconnected porous channels, the evaporator could work stably in high concentrations of salt-water (25 wt% NaCl), showing strong salt resistance. Efficient water evaporation, excellent salt resistance, scalable preparation processes, and low-cost raw materials make CPAS extremely promising for practical applications. [ABSTRACT FROM AUTHOR]

Rapid industrialization and ever‐increasing global population culminate in continuous upsurge in freshwater crisis worldwide. The most reliable and promising solution to this crisis is utilizing sea‐water as the freshwater source, and desalination technologies pave the way for efficient production of freshwater from sea‐water. In this regard, membrane‐based desalination method comes forth owing to its' efficient separation, operational ease, and low‐energy consumption. Metal–organic frameworks (MOFs), the most explored crystalline porous materials, show tremendous promise as membrane‐materials for desalination owing to their structural diversity, tunability, and porous voids which provide secondary water channels. Given significant advances are made in MOF‐materials for desalination in the past few years, it is crucial to systematically summarize the recent progress and development of this field. In this review, a brief overview of various saline water systems and prerequisites for desalination are first presented. Then, advanced fabrication strategies MOF‐membranes followed by the recent progress in MOF‐materials for various desalination processes such as reverse osmosis and forward osmosis are systematically summarized. Finally, the authors' perspectives on the unsolved scientific and technical challenges and opportunities for MOF‐integrated membranes toward real‐world implementation are proposed. With further systematic development, MOF‐materials promise to provide an ideal platform for next‐generation desalination technology. [ABSTRACT FROM AUTHOR]

Water desalination technology has emerged as a critical area of research, particularly with the advent of more cost-effective alternatives to conventional methods, such as reverse osmosis and thermal evaporation. Given the vital importance of water for life and the scarcity of potable water for agriculture and livestock—especially in the Kingdom of Saudi Arabia—the capacitive deionization (CDI) method for removing salt from water has been highlighted as the most economical choice compared to other techniques. CDI applies a voltage difference across two porous electrodes to extract salt ions from saline water. This study will investigate water desalination using CDI, utilizing a compact DC power source under 5 volts and a standard current of 2 amperes. We will convert waste materials like sunflower seeds, peanut shells, and rice husks into activated carbon through carbonization and chemical activation to improve its pore structure. Critical parameters for desalination, including voltage, flow rate, and total dissolved solids (TDS) concentration, have been established. The initial TDS levels are set at 2000, 1500, 1000, and 500 ppm, with flow rates of 38.2, 16.8, and 9.5 mL/min across the different voltage settings of 2.5, 2, and 1.5 volts, applicable to both direct and inverse desalination methods. The efficiency at TDS concentrations of 2000, 1500, and 1000 ppm remains between 18% and 20% for up to 8 min. Our results indicate that the desalination process operates effectively at a TDS level of 750 ppm, achieving a maximum efficiency of 45% at a flow rate of 9.5 mL/min. At voltages of 2.5 V, 2 V, and 1.5 V, efficiencies at 3 min are attained with a constant flow rate of 9.5 mL/min and a TDS of 500 ppm, with the maximum desalination efficiency reaching 56%. [ABSTRACT FROM AUTHOR]

Codium fragile (CF) contains various bioactive compounds, but its high salt content (39.8%) makes its use as a functional food challenging. Here, we aimed to optimize the desalination process and verify changes in functionality based on variations in salt and total phenolic contents. To optimize the CF immersion conditions for the lowest salt content and monitor the total phenolic content, a response surface methodology was used. The optimal immersion conditions were as follows: X1 (immersion temperature) = 42.8 °C; X2 (immersion time) = 1.0 h. An inverse correlation was noted between salt content and total phenolic content. Among the post-desalination processes, desalination with centrifugal dehydration (CD) significantly reduced salt content. CD ethanol extract (CD-E) induced the longest sleep duration in the pentobarbital-induced sleep test in ethanol extracts. Moreover, 1000 mg/kg CD-E had a significant effect on non-rapid eye movement sleep but did not affect delta activity. These findings highlight the potential of industrializing CF as a functional food through desalination and its promise as a natural aid for sleep promotion. [ABSTRACT FROM AUTHOR]

Sustainable development of islands cannot be achieved without the use of renewable energy to address energy and freshwater supply issues. Utilizing the widely distributed tidal current energy in island regions can enhance local energy and water supply security. To achieve economic and operational efficiency, it is crucial to fully account for the unique periodicity and intermittency of tidal current energy. In this study, a tidal current-powered freshwater and energy supply system is proposed. The marine current turbine adopts a direct-drive configuration and will be able to directly transfer the power of the turbine rotation to the seawater pump to improve the energy efficiency. Additionally, the system incorporates batteries for short-term energy storage, aimed at increasing the capacity factor of the electrolyzer. A simulation is conducted using measured inflow velocity data from a full 12 h tidal cycle. The results show that the turbine's average power coefficient reaches 0.434, the electrolyzer's average energy efficiency is 60.9%, the capacity factor is 70.1%, and the desalination system's average specific energy consumption is 6.175 kWh/m3. The feasibility of the system design has been validated. [ABSTRACT FROM AUTHOR]

The research focuses on desalting and regenerating wastewater using membrane capacitive deionization (MCDI) systems with Prussian blue analog and activated carbon electrodes in batch experiments. The experimental results show that the optimized operational parameters for achieving superior deionization regeneration performance in membrane capacitors comprise a voltage magnitude of −1.6 V, a desorption flow rate of 30 mL min−1, and an electrode regeneration duration of 25 min. The MCDI system achieves a desorption amount of 45.87 mg g−1, a remarkable regeneration rate of 99.23 % under the optimized operating conditions. The MCDI system demonstrates a desorption amount and regeneration rate that are 22.56 mg g−1 and 17.47 % higher, respectively, compared to the traditional capacitive deionization system. [ABSTRACT FROM AUTHOR]

Low‐temperature differential evaporation constitutes a promising direction for energy‐saving desalination. Herein, a novel Janus interfacial structure with well‐ordered micro/nanopores is developed. Fabricated Janus interfacial structure can weak the water intermolecular forces and pump water to the hydrophilic–hydrophobic junction. Within well‐ordered nanochannels, the increased curvature of the meniscus increases the ratio of thin water layers, thereby enhancing microscale heat transfer at the heated walls; in addition, the smaller nanopores limit the development of microscale vortices at the liquid–gas interface and prevent back mixing of intermediate water at the interface, which possess the nanoscale effect on intensifying the interfacial evaporation. These effects are validated by theoretical and experimental studies. Optimized Janus (20 nm)95°/25° structure exhibits evaporation fluxes up to 2.4 kg m−2 h−1 at 45 °C (feed side)/25 °C (permeate side, ambient pressure), as the theoretical evaporation enthalpy is only 30% of that for direct evaporation. The unique Janus structure simultaneously inhibits salt accumulation and achieve self‐cleaning, thereby maintaining steady performance during 480 h of continuous desalination and 50 cycles of batch operation. This work highlights a promising structural design strategy for separation materials with specific micro/nanoscopic topologies to achieve high performance thermally driven desalination applications. [ABSTRACT FROM AUTHOR]

Water scarcity is a major issue in cities situated at the Caspian regions of Kazakhstan. To overcome this issue, two compression heat pump-assisted solar thermal desalination configurations are proposed in this research. A numerical model using the TRNSYS simulation package was developed to predict the energy performance of the proposed systems and was validated with experimental results available in the open literature. The influence of ambient parameters and water depth in the basin of a solar still and insulation thickness was analyzed. The performance of proposed configurations is compared with conventional solar still. The errors noticed at 2 and 10 cm depths are 23.6% and 12.1%, respectively. The simulation results confirmed that the heat pump-assisted regenerative solar still configuration has a 91.1%, 73.0%, 61.6% and 82.6% improved productivity during winter, spring, summer and autumn climates, respectively. The results confirmed that significant improvement in freshwater production was observed with heat regeneration compared to the configuration without heat regeneration. The maximum freshwater production with heat regeneration reached 18.0 kg m−2 day−1 in summer and 9.0 kg m−2 day−1 in winter. The optimal water depth in the basin is observed to be in the range between 0.5 and 2.0 cm, while the insulation thickness is between 5.0 and 7.0 cm. The results confirmed that the proposed configuration satisfies the water requirements in Kazakhstan. [ABSTRACT FROM AUTHOR]

The development of absorber materials with strong light absorption properties and low-cost fabrication processes is highly significant for the application of photothermal conversion technology. In this work, a mixed powder consisting of NaCl, polypropylene (PP), and scale-like carbon flakes was ultrasonically pressed into sheets, and the NaCl was then removed by salt dissolution to obtain porous carbon polypropylene composite sheets (P-CPCS). This process is simple, green, and suitable for the low-cost, large-area fabrication of P-CPCS. P-CPCS has a well-distributed porous structure containing internal and external connected water paths. Under the dual effects of the carbon flakes and porous structure, P-CPCS shows excellent photothermal conversion performance in a broad wavelength range. P-CPCS-40 achieves a high temperature of 128 °C and a rapid heating rate of 12.4 °C/s under laser irradiation (808 nm wavelength, 1.2 W/cm2 power). When utilized for solar steam generation under 1 sun irradiation, P-CPCS-40 achieves 98.2% evaporation efficiency and a 1.81 kg m−2 h−1 evaporation rate. This performance means that P-CPCS-40 outperforms most other previously reported absorbers in terms of evaporation efficiency. The combination of carbon flakes, which provide a photothermal effect, and a porous polymer structure, which provides light-capturing properties, opens up a new strategy for desalination, sewage treatment, and other related fields. [ABSTRACT FROM AUTHOR]

Graphene nanoplatelets with high thermal diffusivity are being researched for their ability to improve the thermal characteristics of adsorbents. Similarly, ionic liquids with hydrophilic properties have shown promising sorption and thermal attributes. In this study, novel composite adsorbents are developed, comprising few-layered graphene nanoplatelets and specific ionic liquids (ethyl-methylimidazolium methanesulfonate (EMIMCH3SO3) and ethyl-methylimidazolium chloride (EMIMCl)), along with polyvinyl alcohol binder. The composites, known as GP-CL-30-CP and GP-CH3SO3-30-CP, each contain 30% ionic liquid content. The aim is to capitalise on the superior thermal properties of graphene nanoplatelets and the stability and solvation characteristics of ionic liquids to enhance water and cooling production in adsorption-based cooling and desalination processes, addressing challenges in the water–energy nexus. The findings revealed an improvement in the thermal diffusivity of the composites by 167%, which is 76 times higher than the baseline silica gel. There was an increase in water uptake from 0.3534 kg/kg for silica gel to 0.9648 kg/kg for the composites, representing a 174% enhancement in water sorption, and hence more freshwater water production. [ABSTRACT FROM AUTHOR]

The paper presents a novel control algorithm for a standalone Photovoltaic Reverse-Osmosis (PV-RO) system without a battery. It highlights the importance of tracking the maximum power tracking points in the photovoltaic panels. The development of new methods has become more urgent than before. The PV-RO system combines solar energy and reverse osmosis technology to provide reliable and sustainable access to clean drinking water in remote areas. Traditional PV-RO systems often require energy storage solutions such as batteries to maintain a constant water supply during periods of low solar irradiation. However, the integration of batteries adds complexity, cost, and environmental impact to the system. The paper presents the development of different MPPT techniques, which are better than traditional techniques (more accurate and faster). The paper also provides a comparison with the studied methods (P&O and Incremental Conductance) and the proposed one. [ABSTRACT FROM AUTHOR]

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The perfect combination of renewable energy and desalination technologies is the key to meeting water demands in a cost-effective, efficient and environmentally friendly way. The desalination technique by humidification-dehumidification is non-conventional approach suitable for areas with low infrastructure (such as rural and decentralized regions) since it does not require permanent maintenance. In this study, this technology is implemented by using solar energy as a source of thermal power. A seawater desalination unit is considered, which consists of a chamber with two evaporators (humidifiers), a wetted porous material made of a corrugated cellulose cardboard and a condenser (dehumidifier). The evaporation system is tested with dry bulb temperature and relative air humidity data. The results of numerical simulations indicate that higher inlet air velocities (from 0.75 to 3 m/s) lead to a decrease in the ΔT, ΔRH, and effectiveness. With the air remaining within the evaporator for 30 cm, the temperature differential increases to 5.7°C, accompanied by a 39% rise in relative humidity contrast. These changes result in a significant enhancement in humidification efficiency, achieving a remarkable efficiency level of 78%. However, a wettability value of 630 m2/m3 leads to a smaller reduction of these parameters. Increasing the pad thickness, particularly to 0.3 m, improves performance by boosting ΔT, ΔRH, and effectiveness, especially for pads with a wettability of 630 m2/m3, for which superior performances are predicted by the numerical tests. [ABSTRACT FROM AUTHOR]

Sulfonated poly(oxy‐1,4‐phenylene‐oxy‐1,4‐phenylenecarbonyl‐1,4‐phenylene) also known as SPEEK is a chemically robust cation conductor with good solution processability. A thin film (approx. 0.7 μm) coated asymmetrically over a 10 μm diameter microhole in a Teflon substrate film (5 μm thickness) produces ionic diode effects in aqueous electrolyte media even at high ionic strengths up to 2 M NaCl. The enhancement in the ionic diode performance under high salt conditions is tentatively attributed to a (partial) switch from a concentration polarisation effect (dominant for high diode currents) to interfacial polarisation (dominant at low current; proposed for molecularly rigid ionomers). Ionic strength effects on the diode performance seem relatively low further indicative of a mechanism for the diode effect caused by interfacial polarisation without significant concentration polarisation. Preliminary comparison of diode phenomena in aqueous HCl, LiCl, NaCl, and MgCl2 reveals cation specific effects due to interaction with the polymer. [ABSTRACT FROM AUTHOR]

Freshwater resources have faced serious threats in recent decades, primarily due to rapid population growth and climate change. Seawater desalination has emerged as an essential process to ensure a sustainable supply of freshwater to meet the global demand for freshwater. However, this approach has some shortcomings, such as the disposal of brines containing high levels of contaminants creating environmental problems, and the energy-intensive nature of desalination, primarily powered by fossil fuels, which contribute to greenhouse gas emissions. Consequently, as a solution, the zero liquid discharge approach has been identified by the body of research to be one of the viable methods to solve these problems. Over 90% of freshwater and reusable salts could be recovered through this approach. Adopting renewable energy-powered systems could make zero-liquid discharge desalination plants operate in an entirely environmentally friendly and sustainable manner. This review explores the integration of renewable energy-powered systems for the optimisation of seawater desalination treatment processes for zero-waste and improved productivity. The review also examines technologies and strategies that improve the efficiency and sustainability of desalination systems. By analysing recent research, we provide insights into the advancements, challenges, and prospects for optimizing renewable energy-powered seawater desalination processes aimed at achieving zero waste. [ABSTRACT FROM AUTHOR]

Seawater desalination is increasing due to the global water crisis, and velocity caps are widely used at intake entrances to protect marine life and facilitate the required flow. Despite various investigations of seawater intake, a lack of precise research on the discharge coefficient of these structures is evident. The discharge characteristics of seawater intake are investigated both analytically and experimentally. Results show that the circle velocity caps have higher capacity than square ones, about 2% to 3.5%. Also, the Froude number of approach flow and the area of the velocity caps are the two parameters with the greatest impact on discharge coefficients. However, the height of caps and the number of separator blades have the least effect. Furthermore, some equations of discharge coefficients are developed based on machine-learning techniques with appropriate accuracy. Additionally, the Taguchi method, evaluated as an economical approach, significantly reduces the number of tests while the accuracy of results decreases. [ABSTRACT FROM AUTHOR]

In this study, the effect of using a hybrid solar thermal-activated adsorption desalination system for brackish water is evaluated under the climatic conditions of the Brazilian semiarid region. The proposed theoretical model utilizes climatic data from the meteorological station in Campina Grande, PB, and adsorptive kinetics data of Fuji Davison RD 260 silica gel to predict the performance indices of the specific daily water production (SDWP), specific cooling power (SCP), and coefficient of performance (COP) performance coefficients over a characteristic day. The SDWP value of 6.26 m3/ton, SCP ranging from 50 to 300 W/kg, and an average COP of 0.5 were obtained, considering variations in global horizontal irradiance in the ACDS system and transient ambient temperature. It was observed that both the production of desalinated water and the refrigeration effect increase with the rise in daily solar irradiance. The variation in the number of solar collectors used in the system and their optimality, as well as the variation in the salinity index of the feed source, impacted the evaluated performance coefficients. [ABSTRACT FROM AUTHOR]

The effect of carbonization temperature on thin-film carbon membranes prepared by carbonization of sorbitol and intended for pervaporation desalination was investigated. Thermal properties, functional groups, phase structures, and surface morphology of the prepared carbon and membrane materials were studied by thermogravimetric analysis (TGA), Fourier-transform infrared spectroscopy, x-ray diffraction and scanning electron microscope, respectively, while the membrane performance was evaluated in the pervaporation process. At 400 °C, the TGA revealed a drastic decrease in the sorbitol mass, which correlated with the loss of hydroxyl groups, leaving C–C and C=C groups as carbon materials. Regardless of the applied carbonization temperature, all carbon materials have an amorphous phase; carbonization temperature affects the surface morphology of the carbon membrane, both surface contours and layer thickness, which is directly proportional to desalination performance. The membrane performance was investigated using 1 wt.%, 3.5%, and 7% NaCl solutions at different feed temperatures. Higher carbonization temperatures produce membranes with superior separation performance. The sorbitol-derived carbon membrane carbonized at 350 °C with a concentration of 3.5% and feed solution temperature of 60 °C yielded the best desalination performance, where salt rejection was > 99.9% and water flux was 17.35 kg m−2 h−1. The carbon membrane exhibited excellent salt rejection, close to 100%. It can maintain the separation performance for up to 100 working hours, indicating that the carbon membrane from the sorbitol precursor has the potential to be utilized as a long-term pervaporating membrane. [ABSTRACT FROM AUTHOR]

In this paper, a method is proposed for the complex treatment of technical waste water containing essential concentrations of organomineral impurities including 1 g/dm3 of copper ions. Plasma treatment decreases the chemical oxygen demand of a solution by 17 times, the content of salts by 34%, and the copper and iron concentration by 20%. Electrodialysis decreases the total salt content from 3 to 0.2 g/dm3 and brings the copper and iron content to 8 and 3 mg/dm3, respectively. The destruction of organic substances contained in the water under plasma treatment results in a carbon-containing precipitate studied by physicochemical methods to determine structural and sorption characteristics. The FTIR spectrum of the carbon-containing precipitate indicates the presence of hydrophilic groups and a great amount of uncompensated active sites and free radicals, which can be used in sorption processes. The prospects of using the carbon-containing precipitate as a filler for the desalination chambers of an electrodializer under electrical field application is shown. [ABSTRACT FROM AUTHOR]

Highlights: Steel tip arrays were used as current collectors to replace planar conductors. Optimal flow and electric fields reduced barriers for electron and ion transport. Desalination performance of flow-electrode capacitive deionization is enhanced by the tip-array current collectors. Low-electrode capacitive deionization (FCDI) is an emerging desalination technology with great potential for removal and/or recycling ions from a range of waters. However, it still suffers from inefficient charge transfer and ion transport kinetics due to weak turbulence and low electric intensity in flow electrodes, both restricted by the current collectors. Herein, a new tip-array current collector (designated as T-CC) was developed to replace the conventional planar current collectors, which intensifies both the charge transfer and ion transport significantly. The effects of tip arrays on flow and electric fields were studied by both computational simulations and electrochemical impedance spectroscopy, which revealed the reduction of ion transport barrier, charge transport barrier and internal resistance. With the voltage increased from 1.0 to 1.5 and 2.0 V, the T-CC-based FCDI system (T-FCDI) exhibited average salt removal rates (ASRR) of 0.18, 0.50, and 0.89 μmol cm−2 min−1, respectively, which are 1.82, 2.65, and 2.48 folds higher than that of the conventional serpentine current collectors, and 1.48, 1.67, and 1.49 folds higher than that of the planar current collectors. Meanwhile, with the solid content in flow electrodes increased from 1 to 5 wt%, the ASRR for T-FCDI increased from 0.29 to 0.50 μmol cm−2 min−1, which are 1.70 and 1.67 folds higher than that of the planar current collectors. Additionally, a salt removal efficiency of 99.89% was achieved with T-FCDI and the charge efficiency remained above 95% after 24 h of operation, thus showing its superior long-term stability. [ABSTRACT FROM AUTHOR]

Efficient 2D membranes play a critical role in water purification and desalination. However, most 2D membranes, such as graphene oxide (GO) membranes, tend to swell or disintegrate in liquid, making precise ionic sieving a tough challenge. Herein, the fabrication of the polyoxometalate clusters (PW12) intercalated reduced graphene oxide (rGO) membrane (rGO‐PW12) is reported through a polyoxometalate‐assisted in situ photoreduction strategy. The intercalated PW12 result in the interlayer spacing in the sub‐nanometer scale and induce a nanoconfinement effect to repel the ions in various salt solutions. The permeation rate of rGO‐PW12 membranes are about two orders of magnitude lower than those through the GO membrane. The confinement of nanochannels also generate the excellent non‐swelling stability of rGO‐PW12 membranes in aqueous solutions up to 400 h. Moreover, when applied in forward osmosis, the rGO‐PW12 membranes with a thickness of 90 nm not only exhibit a high‐water permeance of up to 0.11790 L m−2 h−1 bar−1 and high NaCl rejection (98.3%), but also reveal an ultrahigh water/salt selectivity of 4740. Such significantly improved ion‐exclusion ability and high‐water flux benefit from the multi‐interactions and nanoconfinement effect between PW12 and rGO nanosheets, which afford a well‐interlinked lamellar structure via hydrogen bonding and van der Waals interactions. [ABSTRACT FROM AUTHOR]

Porous hydrogels have been developed to be highly efficient interfacial solar vapor generation materials for obtaining affordable freshwater supplies. However, realizing hydrogel materials with portability, adequate water supply, and durable mechanical properties remains challenging. Herein, a scalable and portable hydrogel with 3D‐shaped recovery, highly efficient water transport, and robust mechanical stability is reported, which is prepared by foaming polyvinyl alcohol (PVA) and modification of phosphotungstic acid (PTA). Due to the interconnected porous structure and highly permeable polymer network, the PVA/PTA‐PH hydrogel has good repetitive compressibility and rapid shape recovery when in contact with water. Combined with light‐absorbing nanoparticles, the PVA/PTA‐PH hydrogel presents an impressive solar evaporation rate of 3.876 kg m−2 h−1 and a photothermal conversion efficiency of ≈94% under 1‐sun irradiation. With 3D‐shape recovery and highly efficient water transport, the compressed hydrogel can be quickly unfolded without human intervention and restored to five times the original size for the working state. The good portability, excellent seawater desalination performance, and simple preparation process are anticipated to make the PVA‐/PTA‐PH hydrogel a promising material to continuously and conveniently produce pure water from seawater. [ABSTRACT FROM AUTHOR]

This study investigated the adaptability of Dunaliella salina to different salinity levels, with an emphasis on growth, pigment concentration, and desalination potential. It was found that among the 21 salinity levels, Salinity 75 produced consistently favorable results in cell count (13.08 × 103 ± 1.41 × 103 cells/mL), dry biomass (2.46 ± 0.06 g/L), pigment content (chlorophyll a = 97,500,000 ± 100,000 pg/L, chlorophyll b = 123,600,000 ± 300,000 pg/L), and desalination (9.32 ± 0.47 reduction). Therefore, Salinity 75 was selected for the final trial (scale-up), which revealed unanticipatedly high cell counts (58.96 × 103 ± 535.22 cells/mL), with the dry biomass weight being statistically different (higher) than expected (4.21 ± 0.02 g/L) (p < 0.0001), most likely due to the high cell count and energy reserve storage for high-salinity adaption in the form of bio-compounds. Pigment growth continued (chlorophyll a = 95,400,000 ± 2,200,000 pg/L, chlorophyll b = 128,100,000 ± 5,100,000 pg/L), indicating pigment production under salt stress. Notably, desalination did not occur in this stage, possibly due to the necessity for a bigger initial inoculate, prolonged exposure or bioaccumulation becoming the prevailing mechanism over desalination. Nevertheless, the trial highlights D. salina's strong adaptation to various salinity levels. This suggests a promising future in halophyte research, particularly in understanding the mechanisms that prevent salt accumulation in cells and how to overcome this barrier. Additionally, these results suggest that microalgae could be a viable resource in saline-rich environments unsuitable for conventional agriculture, promoting industrial adaptation to adverse conditions. [ABSTRACT FROM AUTHOR]

Nuclear power is typically deployed as a baseload generator. Increased penetration of variable renewables motivates combining nuclear and renewable technologies into Integrated Energy Systems (IES) to improve dispatchability, component synergies and, through cogeneration, address multiple markets. However, combining multiple energy resources heavily depends on the proper selection of each system's location and design limitations. In this paper, co-siting options for IES that couple nuclear and concentrating solar power (CSP) with thermal desalination are investigated. A comprehensive siting analysis is performed that utilizes global information survey data to determine possible co-siting options for nuclear and solar thermal generation in the United States. Viable co-siting options are distributed across the Southwestern U.S., with the greatest concentration of siting options in the southern Great Plains, although siting with higher solar direct normal irradiance is possible in other states such as Arizona and New Mexico. Brackish water desalination is also attractive across the southwest U.S. due to high water stress, but for brackish water desalination reverse osmosis (an electricity driven process) is most cost- and energy-efficient, which does not require co-siting with the thermal generator. The most attractive state for nuclear and thermal desalination (which is more attractive when using seawater) is Texas, although other areas may become attractive as water stress increases over the coming decades. Co-siting of all CSP and thermal desalination is challenging as attractive CSP sites are not coastal. [ABSTRACT FROM AUTHOR]

Graphene oxide (GO) membranes have good separation performance, but their low water flux and poor stability need further improvement. For this reason, this paper employs a hydrothermal method to prepare reduced graphene oxide (RGO), and utilizes silicon dioxide (SiO2) to intercalate RGO, and then prepares RGO/SiO2 composite membranes by vacuum filtration. The results show that SiO2 intercalation further improves the water flux without loss of rejection and stability. When SiO2 (0. 05 mg/mL) is 3 mL, the pure water flux of the RGO/SiO2 composite membrane is as high as 21. 1 L/(m²·h·bar) which is about 6 times of that of the pure GO membrane, and the retention rate of Na2SO4 is about 83. 7%. The order of rejection for different salts was R(Na2SO4) > R(MgSO4) > R(NaCl) > R(MgCl2). Therefore, the RGO/SiO2 composite membrane has a certain potential for application in desalination. [ABSTRACT FROM AUTHOR]

The majority of the water on Earth roughly 97% is contaminated or salty, only 3% is fresh water, and only 1% of pure water is easily available for human use. In rural areas and remote locations suffering from pure drinking water scarcity.Water purification techniques are generally dependent on electricity, which relies on coal and gas plants, these poses a risk to the environment and society. Solar desalination is being recognized as the most practical way to deal with the scarcity of pure drinking water in all aspects of sustainable development. This paper describes the creation of a single slope solar still (SSSS) using opaque and crystal‐clear toughened glass with a thickness of 6 mm as a cover and also another setup of a single slope phase change material (PCM)‐based solar still (MSSSS). In this paper, a flat plate solar collector coupled with water heater is used to enhance the productivity of still. In this study, an experimental model has been developed to experimentally analyze exercise productivity performance of SSSS and MSSSS of MMIT Kushinagar, India on April 10, 2023 to April 15, 2023. Combination of stearic acid, lauric acid, and paraffin wax combined with CuO (nanoadditive) is used to enhance the solar still productivity. Also, basin temperature for different PCM's such as paraffin wax, lauric acid, and stearic acid are compared. Different combinations of PCM's and nanoadditives are compared to find the better productivity. It is observed that maximum output is obtained at 3:00 p.m. afternoon on experimental setup. Paraffin wax, stearic acid, and lauric acid still increases productivity by 38.8%, 20.3%, and 30.5%, respectively, when compared to simple solar still. On experimentation of various combinations, it is found that the use of PCM paraffin wax and nanoadditives CuO gives 55% better productivity compared to other combinations. This innovative system is suitable and ideal for desalinating water in isolated and rural locations with low traffic and limited demand. [ABSTRACT FROM AUTHOR]

Water scarcity is a serious threat to the survival and development of mankind. Interfacial solar steam generation (ISSG) can alleviate the global freshwater shortage by converting sustainable solar power into thermal energy for desalination. ISSG possesses many advantages such as high photothermal efficiency, robust durability, and environmental friendliness. However, conventional evaporators suffered from huge heat losses in the evaporation process due to the lack of efficient thermal management. Herein, hydrophilic Tencel yarn is applied to fabricate a three-dimensional double-layer fabric evaporator (DLE) with efficient multi-stage thermal management. DLE enables multiple solar absorptions, promotes cold evaporation, and optimizes thermal management. The airflow was utilized after structure engineering for enhanced energy evaporation efficiency. The evaporation rate can reach 2.86 kg·m−2·h−1 under 1 sun (1 kW·m−2), and 6.26 kg·m−2·h−1 at a wind speed of 3 m·s−1. After a long duration of outdoor operation, the average daily evaporation rate remains stable at over 8.9 kg·m−2, and the removal rate of metal ions in seawater reaches 99%. Overall, DLE with efficient and durable three-dimensional multi-stage thermal management exhibits excellent practicality for solar desalination. [ABSTRACT FROM AUTHOR]

The present study endeavours to substantially contribute towards alleviating the global water scarcity problem. The task entailed designing a computational model of a renewable energy-based evaporator. Using ANSYS Fluent, the CFD simulations of a three-dimensional conventional continuous single slope, single basin solar still were carried out in summer at 23.79°N, 86.43°E coordinates. With the optimized inclination condensation angle of 29° and water depth at 1 cm, the solar still recorded the highest hourly drinking water, about 1.5 kg m-2, at 11:00 h. The continuous production resulted in a water collection rate of 8.6 kg m-2 day-1, encompassing the production of all previous models. Additionally, compared with the literature correlation for solar still simulated mass, the Power model calculation was the closest, with a 12.4% variation. Furthermore, the study showcases that CFD is an economical, efficient, and easily diagnosable technique for designing solar stills. [ABSTRACT FROM AUTHOR]

This paper examines the viability of introducing solar thermal desalination technology as a means to supplement existing water production methods in the Republic of South Africa (RSA). The study provides an overview of the current state of desalination technology in the country. A key aspect of this study involves comparing the RSA with the Middle East and North Africa (MENA) region, using publicly available studies and reports. The focus of this comparison is to highlight the potential implementation of large-scale solar desalination in the RSA by evaluating the respective resources and environmental data that directly impact the input and output of a thermal desalination system. The study comparatively analyzes the environmental conditions and seawater salinity of the RSA and the MENA region. The RSA receives a higher solar irradiation range of 4.5–6.5 kWh/m2, whereas the MENA region experiences a range of 3.5–5.5 kWh/m2. Additionally, the salinity of the RSA's seawater ranges between 35 and 35.5 parts per thousand, which is lower than the MENA region's range of 36–40 parts per thousand. The study also reviews and proposes the adoption of an emerging thermal desalination method that has been successfully tested in the MENA region and other countries, based on its performance. [ABSTRACT FROM AUTHOR]

Along with the rapid development of society, freshwater shortages have become a global concern. Although existing desalination technologies have alleviated this pressure to some extent, their long-term environmental impact and energy consumption are still questionable. Therefore, it is necessary to find a new effective way for seawater desalination with cleaner energy. Solar-driven interfacial water evaporation technology has the advantages of environmental protection, energy saving, high evaporation efficiency, low cost, and strong sustainability, and is considered one of the most effective technologies to relieve water resource stress. This review summarized the recent advances in carbon-based interfacial photothermal converters focused on the preparation methods of 2D and 3D photothermal absorbers, the potential ways to enhance the efficiency of photothermal conversion. Finally, this paper proposed the challenges and future trends of interfacial photothermal converters. [ABSTRACT FROM AUTHOR]

In this work, the performance of a Reverse Osmosis (RO) process using different types of reverse osmosis (RO) and nanofiltration (NF) membranes is evaluated for brackish water desalination for producing irrigation-grade water. The proposed desalination system is a single-stage system, where three types of RO and two NF membranes were examined. The different desalination systems were simulated using ROSA72 software. In order to validate the theoretical model, the results obtained from the simulation were compared to those obtained from the experiment conducted in this work. The El-Moghra aquifer of Egypt is considered the test bed due to a considerable amount of data being available for this aquifer. The El-Moghra aquifer has 79 wells, and the available water data, when checked against several quality parameters, show that none of the investigated wells are suitable for direct irrigation without treatment due to problems of salinity, the sodium adsorption ratio, and low water quality according to the irrigation water quality index values. The obtained results show that nanofiltration membranes exhibited superior energy efficiency compared to reverse osmosis membranes. However, what sets the nanofiltration membranes apart is their ability to elevate water quality in 89.9% of the total investigated wells to an acceptable level for agricultural purposes. This underscores the nanofiltration membranes as a highly effective alternative to reverse osmosis membranes, demonstrating the capability to produce water suitable for irrigation while concurrently reducing operational costs due to the lower energy consumption in nanofiltration-based systems. [ABSTRACT FROM AUTHOR]

Environmental context: This manuscript focuses on the introduction of the conventional and modified Solvay processes. The Solvay process is used to produce sodium carbonate and sodium bicarbonate, while also providing brine management and CO2 capture. Optimal values must be used for reactant contents, temperature, salinity of the brine and stirring rate to enhance efficiency. The Solvay process is used to produce sodium carbonate and sodium bicarbonate. Simultaneous brine management and CO2 capture occur by the Solvay process. In this review, the Solvay process based on different solutions (i.e. NH3, KOH, CaO, Ca(OH)2 and alcohol amines) is reviewed. The most efficient processes considering CO2 uptake and Na+/Cl− removal are introduced. The Solvay process benefits from increasing NH3 content, salinity, stirring rate, decreasing temperature and using inert mixing particles in the reactor. Adding NH4HCO3, extra KOH in subsequent stages and brine pretreatment are recommended. The results show that a Ca(OH)2-based Solvay process, an NH3-based process running in contactor and reactor, and a 2-amino-2-methylpropanol-based Solvay process obtain the highest CO2 capture efficiencies of 99, 98 and 80% respectively. Environmental context. This manuscript focuses on the introduction of the conventional and modified Solvay processes. The Solvay process is used to produce sodium carbonate and sodium bicarbonate, while also providing brine management and CO2 capture. Optimal values must be used for reactant contents, temperature, salinity of the brine and stirring rate to enhance efficiency. (Image of the schematic diagram reproduced from with permission.) [ABSTRACT FROM AUTHOR]

Clean water supply in low-income countries can be improved by utilizing affordable renewable energy-powered desalination technologies. In this research work, viability of community scale solar desalination plant (at least 3.0 m3/d capacity) capable of addressing the daily fresh water demands of hundred families in twenty three coastal locations of Somalia has been investigated through year-round simulations. The required desalination plant size and investment is heavily dependent on solar radiation potential of the site. The potable water production cost ranges between 8.66 to 9.48 USD/m3, and is lower than the nonreliable conventional water supply cost in eighteen Somalia coastal locations. Moreover, the desalination plant can sooth at least 2.5 to 13.6-kilo tons of CO2 emission, 6.0 to 33.3-tons of SO2 emission and, 2.30 to 12.6-tons of NOX emission during its 5.0 to 25.0 years operation period. The sustainability index and finance payback time of community scale solar desalination plant is about 1.08, and 4.0 to 13.0 years, respectively. The economics and environmental foot print results indicate feasibility and potential application of community scale solar desalination plant in water starved Somalia coastal locations. [ABSTRACT FROM AUTHOR]

Considering the serious water crisis in the world and the use of saltwater resources of the seas and oceans as available water resources, desalination technology for these waters is to be raised in all societies of the world. Due to the protection and increasing efficiency of desalination methods, the design of a suitable pretreatment method for desalination of salt water has made the process more economic. The methodology used in this research for the analysis of technological schemes includes two groups of technological and economic indicators: (A) water quality data and (B) economic characteristics of the processes. The study is based on a set of experimental projections of water quality data after pretreatments, such as turbidity and the SDI15 (silt density index) index. These data were received from several full-scale systems and full-scale plants. These plants are (1) conventional pretreatment, (2) MF (microfilter) pretreatment, and (3) UF (ultrafilter) pretreatment method. The average SDI15 index of filtrate during the study time provided by the UF and MF systems was 1.5 and 2.9, respectively. The daily decay of permeability by UF and MF systems was 0.86% and 0.45%, respectively. The total cost of the produced water (including investment and O&M) for the conventional treatment full-scale plant, the pretreatment based on the MF membrane, and the UF membrane were obtained at approximately 0.42, 0.46, and 0.55euro/m3 of produced water. Membrane-based pretreatment is a competitive technological alternative to conventional methods. [ABSTRACT FROM AUTHOR]

Polyelectrolytes with strong acidic functionality are among the prime sources for water desalination techniques. Poly 2‐acrylamido‐2‐methylpropanesulfonic acid (PAMPS) is one such polymer showing polyelectrolyte characteristics because of highly acidic SO3H group (pKa < 2) and film‐forming characteristics of flexible polymeric chains. Halloysite nanotubes functionalized with polyelectrolytes can be considered for water purification, as halloysite was reported to be efficient in removing dissolved metal salts. These polyelectrolytes can be introduced as a blend with other components, or they can be synthesized via in situ to form flexible membranes. Polymer nano‐filtration membranes with controlled crosslinking were designed as a function of halloysite and AMPS composition using in situ free radical polymerization with other polymers such as polyvinylidene fluoride and polyvinylpyrrolidone to strengthen the polymer matrix. The synthesized membranes were characterized using FTIR, SEM, EDS, TGA, and DTG techniques. Equilibrium water content, contact angle, water flux, salt rejection efficiency, and antifouling studies are also carried out for these membranes in water purification. [ABSTRACT FROM AUTHOR]

Abstract Chitosan nanosheets (NS) stabilized on poly (3,4-ethylenedioxythiophene): poly(styrene sulfonate) (PEDOT: PSS) was functionalized using Fe3O4 to capacitively remove chloride ions and toxic cadmium ions at optimized pH, concentration, and number of charging cycles. The synthesis procedure was investigated by Fourier transform infrared spectroscopy (FTIR), X-Ray Diffractometer (XRD), Transmission Electron Microscope (TEM), Scanning Electron Microscope – Energy Dispersive X-ray Spectroscopy (SEM-EDS), and Brunauer-Emmett-Teller (BET). The analyses confirms increase in surface area of the nanocomposite from 41 to 132 m2/g and a decrease in crystallinity from 75.3 to 66.9% after nanosheet formation. The highest sorption exchange capacity (SEC) for this work, 93% CdCO3 removal is achieved at 100 CDI cycles while 82% NaCl removal was achieved at 80 cycles. The SEC% increased with pH during Na ion deionization and decreased with pH during Cd removal. The works shows that chitosan is able to impart advanced structural properties to Fe3O4 and PEDOT and is able to reduce reverse migration of ions from electrodes to bulk solution, leading to higher SEC performance.

This study investigated the potential impact of discharged water from the Bousfer desalination plant in Algeria on the marine environment, with a focus on sea urchins that we found overpopulated in the brine discharge area. To assess the presence of heavy metals, which can pose significant ecological and health risks, water samples were collected from the discharge area and analyzed using atomic absorption spectrometry (AAS). The targeted metals included iron, copper, zinc, nickel, and chromium. The results indicated extremely low concentrations of these metals, with values ranging from ≤0.001 to ≤0.01 mg/L. This research is the first of its kind at the Bousfer desalination plant and this site was chosen because this station is scheduled to be replaced by a much larger plant. This study suggests that the levels of heavy metals detected in discharged waters are insufficient to pose a direct threat to sea urchins or humans who consume them. However, given the potential for long-term and cumulative effects, further in-depth studies are needed to assess the overall environmental impact of discharged waters on marine ecosystems, including benthic fauna.

Water contaminants are prevalent in various sources and this poses high risks to the environment as well as human health thereby increasing the need for an efficient sustainable water management. Zeolites are a special type of crystalline aluminosilicate minerals that possess rich frameworks of interconnecting channels and cages. They have exceptionally high cation exchange capacities and has drawn much attention as suitable adsorbent material for the elimination of different types of pollutants in water systems. Besides the use in water purification, zeolites are also used environmentally as filters of toxicants and as sources of nutrition to crops. Zeolites have multiple functions in commercial and environmental processes because of their structural and chemical characteristics. They can act as requisite catalysts, adsorbents, and ion exchangers due to the broad applicability in commercial and environmental processes across industries. This review aims at examining the use of zeolites in different water purification processes with the view of explaining the nature/extent of adsorption properties and ion exchange of the material. The effectiveness of various kinds of zeolites, such as clinoptilolite, chabazite, etc is presented with special reference to the removal of heavy metals, ammonia, organic contaminants, and operation of desalination. Furthermore, the review provides an account of the limitations and comparison with other technologies.