Search Results (293)

Phosphorus recovery from wastewater as struvite via electrochemical magnesium dosing is a promising approach to address the growing demand for fertilizers. However, its large-scale implementation is often constrained by energy requirements. To overcome this limitation, this study investigates electroless struvite precipitation from cheese whey wastewater using sacrificial magnesium anodes. Under optimal conditions, up to 90% of the phosphorus was recovered within 4–6 h. In this process, spontaneous magnesium dissolution acts as the driving force for phosphorus precipitation and is strongly influenced by the wastewater’s ionic composition. To identify conditions that favor efficient recovery, the effects of ammonium, chloride, and sulfate ions were evaluated by monitoring phosphorus removal and magnesium corrosion behavior. Sulfate ions enhanced magnesium corrosion more strongly than chloride during the initial stages, likely due to stronger coulombic interactions with Mg²⁺ at the electrode–electrolyte interface, whereas chloride ions were more effective at disrupting the passivation layer that develops over time. Based on these observations, a mechanistic interpretation of ion-specific effects on anodic corrosion is proposed. Solid-phase analyses using multiple characterization techniques confirmed struvite formation, with ammonium sulfate and ammonium chloride systems yielding the highest product purity. Overall, these findings improve the understanding of electroless struvite precipitation and highlight its potential as an energy-efficient approach for nutrient recovery. Full article

Electrolytic aluminum is one of the most energy-intensive industrial processes and offers strong potential for demand-side flexibility and renewable energy integration. However, existing studies mainly focus on operational scheduling, while comprehensive planning frameworks at the industrial-park scale remain limited. This study proposes an optimal planning framework for electrolytic aluminum that co-optimizes renewable energy investments, waste heat recovery, and green power trading while capturing the temperature safety constraints of electrolytic cells. The electrolytic aluminum process is explicitly modeled with heat exchangers to enable combined cooling–heating–power supply for nearby users. A wind power priority subscription mechanism and green certificate compliance are incorporated to enhance practical applicability and support future decarbonization requirements. Moreover, a two-stage particle swarm-deterministic optimization scheme is developed to provide a tractable solution to the inherently nonconvex mixed-integer nonlinear model. Case studies based on a real plant in Xinjiang, China, demonstrate that the proposed framework can raise the green electricity aluminum share to 60.4%, reduce annual carbon emissions by 52.0%, and significantly increase total system profit compared with the benchmark configuration, highlighting its economic and sustainability benefits for industrial park development. Full article

Low-grade Cu-Ni-PGM concentrators increasingly operate under the combined constraints of declining ore grades, variable process water quality, and the need to optimise reagent suites for sustainable production. This study examines the performance of mixed thiol collectors under controlled inorganic electrolyte conditions representative of modern concentrator water circuits. A comprehensive review of mixed-collector flotation is followed by a bench-scale experimental programme using sodium isobutyl xanthate (SIBX), sodium diethyl dithiophosphate (SEDTP), and their mixtures, tested in synthetic plant water and in CaCl₂ and NaCl solutions at fixed ionic strength. Results show that increasing the SEDTP molar fraction significantly enhances froth stability, water recovery, and solids recovery across all water types, driven by stronger surface activity and the presence of surface-active impurities. Ca²⁺ bearing process water promoted the highest Cu and Ni recoveries but also intensified gangue recoveries at high SEDTP levels, lowering concentrate grades. In contrast, SIBX-rich mixtures yielded superior selectivity, particularly in Na⁺ containing process water. Mechanistic interpretation shows that combined effects of electrical double-layer compression, mineral activation, mixed-collector adsorption, and froth stabilisation behaviour govern the observed grade–recovery trends. Overall, this study demonstrates that thiol-collector synergy is strongly water-chemistry-dependent, and that optimising collector mixtures requires coordinated control of reagent composition and process water quality. The findings provide a mechanistic basis for water-responsive reagent design in Cu-Ni-PGM flotation circuits. Full article

The growing demand for lithium-ion batteries (LIBs) is driving a rapid increase in the volume of spent cells which—as hazardous waste—must be managed effectively in accordance with circular-economy principles. Hydrometallurgical recycling allows the recovery of critical metals at far lower environmental cost than primary mining. This paper presents a method for obtaining metallic nickel from sulfate leach solutions produced by leaching the so-called “black mass” derived from shredded LIBs. Nickel electrodeposition was performed on a stainless-steel cathode with Ti/Ru-Ir anodes at 60 °C and pH 3.0–4.5. Two process variants were examined. Variant A—with a decreasing Ni²⁺ concentration (49 → 25 g L⁻¹)—achieved a current efficiency of 60–88%, but the deposits were non-uniform and prone to flaking. Variant B—in which the bath was stabilized by the continuous dissolution of Ni(OH)₂ (maintaining Ni²⁺ at 35–40 g L⁻¹) and amended with PEG-4000, H₃BO₃ and Na₂SO₄—reached higher efficiency (78–93%) and produced uniform, bright deposits up to 0.5 mm thick with a purity >90%. The results confirm that keeping the nickel concentration constant and appropriately modifying the electrolyte significantly improve both the qualitative and economic aspects of recovery, highlighting electrolysis as an efficient way to process LIB waste and close the nickel stream within the material cycle. Full article

The interaction between clay minerals and electrolyte solutions critically affects waterflooding efficiency in enhanced oil recovery (EOR). This study systematically investigated the adsorption and thermodynamic properties of montmorillonite, illite, and kaolinite in different cationic solutions (K⁺, Na⁺, Ca²⁺, Mg²⁺), integrating adsorption isotherm analysis with immersion calorimetry for the first time. Montmorillonite showed the highest adsorption capacity, with the cation affinity following K⁺ > Na⁺ > Ca²⁺ > Mg²⁺. The highest immersion enthalpy was observed in KCl solution, indicating the dominant roles of ionic radius and solvation energy. Cation adsorption induced deformation of clay lamellae and modification of Si-O and Al-OH groups. These findings suggest that optimizing injected ion composition can enhance reservoir stability and waterflood performance, providing thermodynamic insights for EOR process optimization. Full article

WO₃ nanorods were fabricated following electrochemical anodization of tungsten, under controlled hydrodynamic conditions, in electrolytes containing three distinct carboxylic acids: citric, tartaric and L-aspartic acids, to study the influence of these complexing agents on the morphology and arrangement of the oxide layers. The samples were characterized by FESEM, TEM and XRD, and electrochemical analyses (EIS and ECSA) to assess their potential as anode materials for lithium-ion batteries. This characterization showed the nanostructures anodized in the presence of tartaric acid exhibit uniform morphology and lower total charge transfer resistance associated with the nanostructured layer of WO₃ and cycling stability, resulting in more efficient electrochemical processes, better conductivity and stability, making these nanostructures promising for anodes in lithium-ion batteries. The cycling of the batteries was also conducted to understand the behavior of the nanostructures as anodes against metallic lithium. The results showed that the nanostructures analyzed in the presence of tartaric acid exhibited the best initial specific capacity, improving the capacity provided by the graphite ones. These samples also showed a good recovery after faster cycling. These findings demonstrate the effectiveness of complexing-agent-assisted anodization as a strategy for tailoring WO₃ nanostructures with enhanced electrochemical performance. Full article

The EU’s green transition hinges on secure access to critical raw materials; vanadium is pivotal for microalloyed steels and emerging long-duration energy storage (VRFBs). Methods: We combine a market and technology review with PESTEL and Porter-5+2 analyses, complemented by a value-chain assessment and a SWOT-to-CAME strategy for the EU. Results: Vanadium supply is highly concentrated (VTM-derived, largely in CN/RU/ZA), prices are volatile, and >85% of demand remains tied to steel; yet VRFBs could shift demand shares by 2030 if costs—dominated by electrolyte—are mitigated. EU weaknesses include lack of primary mining and refining capacity; strengths include research leadership, regulatory frameworks and circularity potential (slag/catalyst recovery, electrolyte reuse). Conclusions: A resilient EU strategy should prioritize circular supply, selective upstream partnerships, battery-grade refining hubs, and targeted instruments (strategic stocks, offtake/price-stabilization, LDES-ready regulation) to de-risk vanadium for grid storage and low-carbon infrastructure. This study also discusses supply chain concentration and price volatility, and outline circular-economy pathways and decarbonization policy levers relevant to the EU’s green energy transition. Full article

To investigate interspecific variation in heat tolerance and underlying adaptation mechanisms in Rhododendron, three-year-old potted seedlings of eight taxa, representing four subgenera within the genus Rhododendron, were subjected to 40 °C high-temperature stress. Heat tolerance was comprehensively assessed using phenotypic observation, chlorophyll fluorescence imaging, microscopic examination, and physiological measurements. Results revealed that leaf damage in Rhododendron oldhamii and Rhododendron × pulchrum reached grade III, whereas Rhododendron latoucheae exhibited only grade II injury with rapid recovery. Chlorophyll fluorescence analysis showed a significant decrease in the maximum quantum efficiency of PSII (F_v/F_m) in R. liliiflorum and R. × pulchrum, followed by rapid recovery, while R. latoucheae maintained stable F_v/F_m values. Stomatal closure occurred in all taxa post-stress; stomatal characteristics of R. liliiflorum and R. simiarum remained stable, and leaf tissue structure was least affected in R. kiangsiense. R. × pulchrum demonstrated the most pronounced structural recovery. Physiologically, R. oldhamii exhibited the greatest increases in electrolyte leakage (EL) and malondialdehyde (MDA) content. R. simiarum accumulated the highest proline content under stress, while R. latoucheae showed the most significant proline reduction during recovery. By integrating multiple indicators through principal component analysis (PCA) and a membership function, and assigning weights based on variance contribution, the heat tolerance was comprehensively evaluated and ranked as follows: R. latoucheae > R. simiarum > R. oldhamii > R. ovatum > R. fortunei > R. liliiflorum > R. kiangsiense > R. × pulchrum. These findings demonstrate significant differences in heat tolerance among Rhododendron taxa at the subgenus level, with the subgenus Azaleastrum generally possessing stronger short-term heat tolerance compared to the subgenus Tsutsusi. This study provides a theoretical basis for heat-tolerant cultivar breeding and landscape application of Rhododendron. Full article

Background and Clinical Significanc: Congenital duodenal diaphragm (CDD) is a rare congenital condition causing partial or complete obstruction of the duodenum, most frequently located in the second part of the duodenum. It is a rare but important cause of intestinal obstruction in infants and young children. Clinically, it often presents with persistent vomiting and failure to thrive. Diagnosis can be made through abdominal X-ray showing the characteristic “double bubble” sign, upper gastrointestinal (GI) series, or gastroscopy. Case Presentation: A 17-month-old female infant with known psychomotor retardation was admitted for evaluation of inadequate weight gain and intermittent postprandial vomiting, both present since birth. Laboratory investigations, including metabolic and electrolyte panels, were within normal limits. Given the persistent clinical symptoms, an upper gastrointestinal series was performed to assess for possible anatomical abnormalities. Imaging revealed a significant delay in the passage of contrast into the second portion of the duodenum, with marked prestenotic dilatation. Subsequent gastroscopy identified a duodenal diaphragm nearly occluding the duodenal lumen at the same site, impeding the passage of the endoscope. Associated findings included gastritis and the presence of food debris in the stomach and proximal duodenum, indicating impaired gastric emptying. The patient underwent successful surgical management via duodenotomy with resection of the septum. Postoperative recovery was uneventful. Conclusions: In infants or young children with persistent postprandial vomiting and inadequate weight gain, anatomical causes such as duodenal diaphragm/web should be considered in the differential diagnosis. Once identified, treatment should be initiated promptly, either endoscopically or surgically, depending on the severity and anatomical characteristics of the obstruction. Full article

In this study, a rough-surfaced LiFePO₄ (RS-LFP) cathode material with a well-defined porous architecture was successfully synthesized via a scalable, template-assisted spray drying method. The resulting RS-LFP exhibited a high specific surface area of 41.2 m² g⁻¹, significantly enhancing electrode–electrolyte contact. This tailored microstructure, combined with an in-situ-formed carbon network, reduced the charge-transfer resistance and facilitated efficient ion/electron transport. Consequently, the RS-LFP demonstrated outstanding electrochemical performance, including a high initial capacity of ~140 mAh g⁻¹ at 0.2 C, excellent cycling stability with over 95% capacity retention after 30 cycles, and superior rate capability. The RS-LFP also exhibited a remarkable capacity recovery of ~99% when the current returned to 0.2 C. These findings highlight that engineering porous architectures through template-assisted spray drying is a promising and scalable strategy for developing high-performance phosphate-based cathodes for advanced energy storage applications. Full article

A low-cost screen-printed carbon electrode (SPCE) was used to determine gallic acid (GA) in banana wine (BW). Cyclic voltammetry (CV) showed GA oxidation in Phosphate-Buffered Saline (PBS, pH 7.0) with 10% ethanol was diffusion-controlled, forming a quinone species. This supporting electrolyte was applied for calibration using the identified CV and differential-pulsed voltammetry (DPV) peaks, whose low potentials ensured good selectivity and stability. Linearity was obtained between 0.25–5.00 μM GA, suitable for BW analysis. BW was filtered, diluted (1:20) in electrolyte, and analysed via the standard addition method. GA concentrations were 7.369 μM (CV) and 7.570 μM (DPV), with no significant differences. Further validation of the voltammetric procedure using fortified BW confirmed its reliability, with excellent recoveries of 94.41% (CV) and 99.33% (DPV). The SPCE-based voltammetric approach offers a simple, accurate, and low-cost method for GA determination in BW, combining good sensitivity, selectivity, and reproducibility. Full article

This study aimed to develop and apply a novel zeolite-modified electrode (ZME), integrating Cu-exchanged zeolite Y (Cu-ZY) with a conductive carbon matrix composed of multi-walled carbon nanotubes (MWCNTs), for the sensitive and selective voltammetric determination of agomelatine (AGO), an important antidepressant, the accurate determination of which in pharmaceutical and biological samples is critical for therapeutic monitoring and quality control. Drop-casting the Cu-ZY/MWCNTs composite onto the surface of a glassy carbon electrode (GCE) resulted in the formation of a unique sensing platform, which exhibited a significantly improved electrochemical response for the oxidation of AGO. The enhanced activity of Cu-ZY/MWCNTs-GCE, attributed to the synergistic combination of Cu-ZY and MWCNTs, was confirmed by morphological, textural, and voltammetric analyses. Differential pulse voltammetry (DPV) was utilized for the quantitative determination of AGO, with optimization performed on instrumental parameters, supporting electrolyte pH, and preconcentration time (t_acc). Using the Britton–Robinson buffer (BRB) solution at pH 3.0, the Cu-ZY/MWCNTs-GCE exhibited a linear response to AGO concentrations ranging from 8.2 × 10⁻⁹–9.6 × 10⁻⁷ mol L⁻¹ (0.002–0.23 mg L⁻¹), achieving a detection limit (LOD) of 4.3 × 10⁻⁹ mol L⁻¹ (1.04 µg L⁻¹) with a preconcentration time of 60 s. The successful determination of AGO in pharmaceutical formulations, wastewater, and biological fluids, with recoveries ranging from 98.0 to 113.0%, demonstrates the effectiveness and practical applicability of the Cu-ZY/MWCNT-GCE-based voltammetric method for agomelatine analysis in complex matrices. Full article

Background/Objectives: Colonoscopy, a common outpatient procedure requiring bowel preparation, can lead to dehydration and electrolyte disturbances. Sedation, while improving patient comfort, may exacerbate these effects and contribute to orthostatic hypotension (OH) and postural orthostatic tachycardia syndrome (POTS). This study aimed to determine the prevalence of OH and POTS following sedated colonoscopy and to identify associated risk factors. Methods: This prospective observational study included 76 adult patients (ASA I–III) who underwent colonoscopy with fentanyl–propofol sedation between August and November 2024. Blood pressure, heart rate, and orthostatic intolerance (OI) symptoms were assessed before and after mobilization. OH was defined as a systolic blood pressure decrease ≥20 mmHg or diastolic decrease ≥10 mmHg upon standing. POTS was defined as a heart rate increase ≥30 bpm or an absolute heart rate ≥ 120 bpm. Statistical analyses were performed using SPSS 29.0. Results: Post-procedural OH and/or POTS occurred in 18 patients (23.7%), and 14 patients (18.4%) reported OI symptoms such as dizziness, nausea, or blurred vision. Symptomatic patients were significantly younger than asymptomatic patients (42.7 ± 15.4 vs. 54 ± 13.9 years, p = 0.009), and symptoms were more frequent among females (p = 0.046). Preoperative diastolic blood pressure was significantly higher in patients who developed OH (p = 0.022), while other hemodynamic and demographic variables showed no significant associations. Conclusions: Orthostatic hypotension and postural tachycardia are relatively common after sedated colonoscopy. Younger age and female sex were identified as independent risk factors for OI symptoms, suggesting a possible role of autonomic variability. Routine post-procedure monitoring and assisted mobilization before discharge may improve patient safety and recovery outcomes. Full article

This work investigates the role of preload pressure in governing the electro-chemo-mechanical (ECM) behavior of lithium iron phosphate (LFP)/graphite pouch cells during calendar aging. Cells aged at 60 °C under different preload levels were systematically evaluated through in situ monitoring of force evolution and capacity retention. To interpret these behaviors, a coupled model was developed that integrates solid electrolyte interphase (SEI)-induced electrode expansion, viscoelastic relaxation, and stiffness evolution, and it was validated against multi-rate discharge experiments, showing excellent agreement with measured voltage and force responses. The results reveal that higher preload amplifies internal pressure fluctuations, prolongs viscoelastic relaxation, and delays irreversible force recovery, while the overall capacity fade remains largely unaffected. A slight mitigation in capacity loss is observed at high preload, primarily due to suppressed SEI growth resulting from reduced electrode porosity and a decrease in active surface area available for interfacial reactions. Fitting parameters for stiffness correction, relaxation amplitude, and relaxation time exhibited systematic preload dependence. By decoupling irreversible and relaxation forces, the framework enables quantitative analysis of aging-induced pressure accumulation. Overall, this study underscores the critical role of mechanical constraints in long-term battery degradation and demonstrates the predictive capability of the proposed ECM model for guiding preload design in practical modules. Full article

The article describes oxygen gasification installation for waste biomass in waste-to-fuel technology, in which the final product is liquid methanol (the reference case). A comprehensive techno-economic model integrates oxygen-based gasification of wet sludge with three waste-heat recovery technologies—expander, Stirling engine, and organic Rankine cycle—and directs the recovered electrical power to a PEM electrolyzer for additional hydrogen production. The model captures full material flows, thermodynamic efficiencies, CO₂ balances, and an economic analysis over a 20-year horizon. A comparison of the use of an expander, Stirling engines, and ORC modules to power the electrolytic hydrogen generation installation was proposed. The produced hydrogen is an additional substrate for the methanol reactor, which will consequently increase the methanol yield from the entire installation and reduce the specific CO₂ emissions. Oxygen from the electrolysis process can be used in the gasifier, which will reduce the energy consumption of the Air Separation Unit, and thus increase the efficiency of the entire gasification system. In addition to the technical evaluation, an economic analysis was carried out to assess the profitability of the proposed concepts, showing that process integration can significantly improve both energy performance and economic feasibility of methanol production in waste-to-fuel systems. Results show that proposed modifications have the potential to increase overall efficiency from 75.498% (reference scenario) to even 82.545% (best scenario), while specific emissions of carbon dioxide drop from 1.746 kg CO₂/kg CH₃OH (reference scenario) to 1.468 kg CO₂/kg CH₃OH (best scenario), with an increase in methanol yield of about 9.4% (from 0.255 kg CH₃OH/kg Bio in reference scenario to 0.279 in best scenario). Full article