This study aims to develop proton exchange membranes that can be effectively utilized in energy systems like fuel cells, batteries, etc. These systems play an important role in developing green energy solutions for the sustainable environment. This research mainly focuses on fabricating various proton exchange membranes using different polymers and nanomaterials. The aim was to fabricate proton exchange membranes that can be used in energy systems such as fuel cells. Incorporating SPEEK and metal organic framework has enhanced the membranes water uptake and ion exchange capacity. The functionalized polymers showed higher proton conductivity when incorporated in different matrices. In contrast, the membranes showed lesser conductivity when added together in the same matrix. The PES/SPEEK/MIL-100(Fe) have achieved highest proton conductivity of 6.324 × 10–5 S/cm respectively, due to the presence of sulfonic acid group and the proton conductive nature of MIL-100(Fe). The chemical stability of membranes has reduced upon addition of SPEEK and MIL-100(Fe). Overall, PES/SPEEK/MIL-100(Fe) demonstrates significant potential to enhance proton exchange membrane performance.

The unique properties of metal–organic frameworks (MOFs), such as their high surface area, adjustable pore structure, and diverse chemical function, have led them to be a new class of crystalline porous materials. Due to these properties, MOFs have a wide range of uses in the energy and environmental fields, including gas storage and separation, carbon capture, catalysis, sensing, energy storage, wastewater treatment, and the remediation of pollutants. This article presents a review of MOFs structural properties, synthesis methods, classification schemas, and characterisation techniques. It will consider MOFs environmental applications, including: CO2 capture, dye adsorption, heavy metal removal and the filtration of particulate matter, as well as MOFs' energy applications, specifically: gas storage, electrocatalysis, photovoltaics, and energy conversion systems. The review also cover recent advances in MOF design and functionality through newly developed computational modelling tools and modification techniques, as well as provide an analysis of the practical issues facing MOFs related to their scalability, stability, and implementation, while summarising future research needs

Among the most energy and cost-efficient flue gas after-treatment technologies is the catalytic oxidation of harmful emissions including carbon monoxide and organic gaseous compounds (OGC). The present work aims to shed light on the transition of lab-scale research under ideal conditions toward realistic experiments focusing on the catalytic oxidation of carbon monoxide (CO), as the simplest pollutant via Pt-Pd monolithic catalyst. The catalytic testing demonstrated that the conversion curves could be divided into three major, almost linear parts (A, B and C) and two transition parts, with part B being much steeper, implying that a minor change in flue gas temperature causes a significant change in CO conversion rate. Part B is considered as a measure of the catalytic activity considering that the steeper the increase the better the catalytic performance as it approaches the full conversion. The comparison of the conversion curves of the artificial and realistic flue gas experiments demonstrated a shift towards higher temperatures (30 - 40 degrees C) in part B, indicating that in the realistic flue gas, there are inhibiting factors such as water vapour and/or CO2, especially at lower temperatures (<200 degrees C) where the adsorption process of these species is favoured.

This study evaluates the suitability of defined solid recovered fuel (SRF) both as a standalone feedstock and as a wood-blended fuel. The experiments were conducted using an air-blown autothermal gasification reactor equipped with a circular grate, with atmospheric air serving as the oxidizing agent. The results indicate that both fuel configurations are suitable for gasification, resulting in a stable process and production of methane-rich producer gas production with high CH4 content of 14-15%vol.. The LCA analysis determines the pelletisation process and evaluates its benefit within a transportation framework, which reduces environmental impacts for transport distances exceeding approximately 200 km due to improved energy density. This research study highlights an experimentally evaluated alternative to waste-to-energy processes, where material valorisation is of the essence for converting high-calorific waste fractions into gaseous energy carriers and solid carbon-rich residues. Equilibrium-based modeling was additionally applied to provide a theoretical reference for syngas composition during air-blown gasification and was compared with experimental results. Moreover, waste management of non-recyclable, high-calorific waste fractions can be partially solved through this approach, as was found in this study. These findings support the role of SRF gasification as a complementary waste valorisation route for non-recyclable, high-LHV waste streams.

Gram-positive bacteria are essential for the structural stability and functionality of biofilms in microbial electrochemical systems (MESs). This study evaluated the effects of lysozyme-induced disruption of Gram-positive bacteria on the microbial electrolysis cell (MEC) performance and biofilm composition. Lysozyme treatment reduced biofilm thickness by 37.7% and biomass by 80% due to the peptidoglycan hydrolysis and increased cell lysis, leading to higher proportions of dead cells in both the anode (18.02 to 57.7%) and the cathode (21.9 to 55.2%) biofilms. However, the metabolic capacity of anodic microorganisms (59 to 360 Coulomb produced by 1010 microorganisms) was enhanced due to enhanced cell permeability and a looser biofilm structure that facilitated electron transfer. Conversely, the cathodic performance of the electron recovery efficiency decreased (from 81.97 to 70.92%), and the H2 and CH4 productions were reduced by 43 and 11%, respectively. This was attributed to the loss of key Gram-positive species and weakened microbial network connectivity. Network analysis revealed enhanced modularity at the anode with stabilized performance, whereas the cathode network was sparse and had impaired microbial interactions. These findings have accentuated the dual roles of Gram-positive bacteria in maintaining biofilm stability and microbial interactions, influencing discrete anode and cathode processes.

Methane production rate has been a major obstacle hindering the widespread adoption of anaerobic digestion (AD) process. This study investigated the synergistic effects of magnetite and an external magnetic field on anaerobic sludge, with a focus on methane production, volatile fatty acids (VFAs), and microbial community structure. The group treated with both magnetite and a magnetic field (DM) exhibited the highest methane yield (69.16 ± 5.56 mL/g biomass), nearly double that of the blank control group (BC, 37.50 ± 1.59 mL/g biomass), along with the shortest lag phase in kinetic modeling (0.96 ± 0.13 d vs 1.52 ± 0.13 d by BC), indicating a faster microbial response. DM treatment also resulted in more rapid VFAs consumption, especially of acetic acid and propionic acid, suggesting enhanced metabolic activity and substrate conversion efficiency. The dominant genera in all the groups were Enterococcus, Proteiniphilum, Acetomicrobium, and Candidatus Caldatribacterium. Diversity analysis, simper analysis, and network attribute difference analyses have all indicated that the overall microbial community structure in the bulk sludge remained stable, and magnetite had influenced microbial activity on its surface. These research findings have demonstrated that magnetite and magnetic fields synergistically enhanced AD efficiency by stimulating microbial activity without altering the microbial community structure. These outcomes have provided valuable insights for developing bioaugmentation strategies for enhanced biogas production.

Contaminated wastewater is produced as an inevitable by-product in many industrial applications. This paper thoroughly investigates the toxicity and environmental burden of wastewater from the Fischer-Tropsch catalytic synthesis process. This significant by-product was analysed through the means of root growth inhibition of Sinapis alba, acute lethal effects on Eisenia andrei, chromatography on organic compounds, and determination of the content of metals. Two samples based on Co and CoMnK fixed bed catalytic synthesis using a standard range of parameters (250-280 degrees C; 1.5 MPa; 1145 h-1) were prepared. The results showed a severe toxicological effect in all investigated means. Significant Co, Mn, and K occurrences were detected in wastewater in amounts of 0.40-0.57, 0.83, and 0.13 mg & sdot;l-1, respectively. The root growth inhibition test proved that only 9.85 % solution is necessary to reach a 50 % growth inhibition in the case of Co synthesis. CoMnK synthesis presented slightly less toxic results-11.75 % solution for 50 % growth inhibition. Similarly, Wastewater Co with lethal concentration LC50 87.74 % was more toxic to earthworms than Wastewater CoMnK with LC50 95.99 %. The level of toxicity of this widely produced substance was surprisingly high. Rising environmental protection activity is expected to prove problematic for the current or future industrial applications, and a need to adopt treatment processes discussed in this study or upgrade the existing ones might be of the essence. The issue of wastewater toxicity and its environmental impact are discussed and evaluated hereby.

Palladium (Pd) is recognized as a promising electrocatalyst for electrocatalytic hydrodehalogenation (ECH). However, the agglomeration-prone nature of Pd nanoparticles diminishes active site accessibility, significantly compromises their atomic utilization efficiency, thereby limiting ECH performance. To overcome this issue, a nickel (Ni)-catalyzed graphitized cyanobacterial biochar (GCBNi) has been developed through catalyst screening and process optimization. The incorporation of Ni enhanced the ordering of carbon arrangement in the biochar, endowing GCBNi with a highly graphitized structure, superior electrical conductivity, and substantial surface area. Pd nanoparticles were supported on GCBNi to fabricate the Pd@GCBNi catalyst. The Pd@GCBNi/CC electrode exhibited well-dispersed Pd nanoparticles, where GCBNi modulated the Pd(0)/Pd(II) ratio and promoted the exposure of Pd(111) crystallographic planes. This structural modification increased accessible active sites, facilitated reactive atomic hydrogen (H*) generation, and improved both adsorption of florfenicol (FLO) and desorption of intermediate products. The Pd@GCBNi/CC electrode demonstrated exceptional FLO removal efficiency (99.6 %+/- 0.4 %) with an apparent rate constant (kobs) of 1.01 +/- 0.08 h-1. Remarkable stability was maintained through ten consecutive operational cycles, with superior ECH performance towards various halogenated organic pollutants containing different halogen substituents. This research provides novel insights into cyanobacterial resource utilization and establishes an effective support modulation strategy for developing highperformance ECH catalysts.

Triclosan (TCS) is extensively detected in wastewater and waste-activated sludge (WAS). The occurrence and fate of TCS in anaerobic digestion have been well revealed, but the change in TCS during WAS pretreatment needs to be clarified. Thermal hydrolysis pretreatment has been proven to be efficient for both WAS hydrolysis and TCS removal, with a removal efficiency of 54.0% and a retention time of 90 min at 170 °C. Alkaline pretreatment remarkably changed the TCS distribution between the sludge and liquid, and the solid–liquid distribution coefficient decreased by three orders of magnitude as the pH increased to 13. Neither alkaline pretreatment nor thermal–alkaline pretreatment resulted in the obvious removal of TCS. UP demonstrated limited efficiency in the hydrolysis of WAS, as well as the migration and removal of TCS. Thus, this study demonstrated that pretreatment methods and operational parameters significantly influence the migration and removal of TCS. It also provides a valuable reference for future studies on the migration and degradation behavior of TCS during anaerobic digestion and lays a foundation for the development of WAS treatment engineering capable of efficiently removing TCS.

The efficient elimination of emerging contaminants (ECs) and residual total nitrogen (TN) from secondary effluents has emerged as a critical challenge for sustainable development goals. In this study, an innovative and intimately coupled photocatalysis and biodegradation (ICPB) system was designed and operated to eliminate the model EC, ciprofloxacin (CIP), along with TN from secondary wastewater. By employing a conductive carbon paper as a carrier and positioning the photocatalyst and biofilm on opposite sides, this configuration effectively mitigated the interference between photocatalytic and biological processes. Under a hydraulic retention time of 6 h and a visible light irradiation intensity of 70 mW/cm2, the removal efficiencies for CIP and TN were recorded as 85.1 % f 0.2 % and 50.2 % f 0.1 %, respectively. It was evident that the photoelectrons derived from the CIP photocatalytic degradation process facilitated denitrification, as the carbon-to-nitrogen (C/N) ratio was lowered to 2.59. Compared with the inoculum and dark conditions, microorganisms capable of extracellular electron transfer and autotrophic denitrification were significantly enriched. Functional prediction analysis revealed that the gene expression associated with denitrification and electron transfer was upregulated. Additionally, the ICPB system demonstrated efficacy in treating actual secondary effluent, and the presence of natural organic matter in the secondary effluent further enhanced the simultaneous removal of CIP and TN to 91.7 % f 0.0 % and 80.6 % f 0.2 %, respectively, at a C/N ratio of 2.44. These findings provide an efficient and low-carbon technological alternative for the effective removal of high-risk EC and residual TN from secondary effluents.

This research study investigates sodium acetate trihydrate as a metastable supercooled liquid phase change material for long-term heat energy storage and is an efficient evaluation of various sodium acetate trihydrate-towater ratios and heat exchanger geometries to enhance storage efficiency. Experimental modules with spiral and toroid squiggle heat exchangers were developed to assess energy retention during liquefaction, sensible heat discharge, and latent heat discharge phases. Experimental outcomes indicate that the toroid squiggle design extends latent heat discharge duration by up to 35 min compared to the spiral exchanger, reaching a maximum of 29 min. The optimal sodium acetate trihydrate-to-water ratio was 92 %, balancing high theoretical latent heat capacity (93.6 Wh) and low theoretical to real latent heat capacity ratio with phase stability. The toroid squiggle exchanger with the mentioned accumulation substance demonstrated better heat transfer, maintaining energy output above 100 W for 11 min and above 50 W for 35 min, while the spiral design showed lower values, retaining above 100 W for only 7 min and above 50 W for 26 min. Furthermore, specific heat capacity measurements showed that sodium acetate trihydrate-to-water 92:8 ratio (SAT 92) exhibited specific heat values of 2.1 kJ/kg & sdot;K in the solid phase and 5.0 kJ/kg & sdot;K in the liquid phase, confirming its strong thermal storage potential with minimal phase instability. The conclusions have highlighted the importance of optimizing heat exchanger geometry and sodium acetate trihydrate composition for sustainable energy storage and these significant insights will contribute to improving seasonal heat accumulation technologies, particularly in synergy with renewable energy systems.

The process of gasification is well-known; however, to this day, the applications of such facilities, especially off-grid small-scale units for direct electricity and char production, are scarce. In this study, an off-grid fixed bed downdraft gasification unit is studied from the gaseous/solid product character perspective. This unit represents a possible solution for the emerging call for sustainable decentralised energy sources. Softwood chips were utilised in this study, and their conversion into synthetic gas (direct electricity supply) and solid biochar was observed and analysed. The results show promising values of synthetic gas for potential utilisation in different applications outside the direct combustion process, such as microbial syngas fermentation, with a lower heating value equal to 6.31 MJ·m-3. It appears that during the steam activation process of biochar, both high-quality off-gas of more than 70%vol. H2 (excluding N2) and activated carbon of a specific surface area of 565.87 m2·g-1 can be collected. Further investigations have revealed specific degradation of chemical bonds and material morphology changes during steam gasification. The microporous structure and high specific surface area of the material make it an attractive material for further development as an adsorbent in sorption cooling devices. Therefore, the waste generated within the gasification process is minimised, and the potential of the obtained products will be valued in favour of the sustainability of the remote locations.

Background: Pirimicarb, a commercially used insecticide, contains carbamate, which affects the nervous system of insects and living organisms, thus inhibiting their growth and increasing the production of crops. However, it has an impact on the ecosystem of groundwater by permeating the soil profile. Methods: The g-C3N4, Bi2WO6 & g-C3N4/Bi2WO6 nanocomposites were synthesized by hydrothermal method and grafted on the PVDF membranes via in-situ polymerization. The pirimicarb wastewater of different pH 5,7 & 9 was synthetically prepared, and the performance of the membrane was tested to study the reduction and photodegradation of as-prepared pirimicarb wastewater. Significant: The surface energy had increased from 88.65 to 145.1 mJ/m(2), g-C3N4/ Bi2WO6 nanocomposites on the PVDF membranes. The water contact angle of the membrane ranges from 57.9 degrees to 37.7 degrees, indicating that the membranes have higher hydrophilic characteristics. The water permanence is in the decreasing order of M1 (PAA/PVDF)> M6 (0.5wt% g-C3N4/Bi2WO6/PAA/PVDF)> M3 (1wt% Bi2WO6/PAA/PVDF)> M7 (1wt% g-C3N4/Bi2WO6/PAA/PVDF)> M4 (0.5wt% g-C3N4/PAA/PVDF)> M2 (0.5wt% Bi2WO6/PAA/PVDF)> M5 (1wt% g-C3N4/PAA/PVDF)> Neat (PVDF). The photodegradation studies stated that upon adding nanocomposites such as g-C3N4/Bi2WO6, the membranes undergo degradation of 80% at pH 5, which is higher than the PVDF/PAA (M1) membrane.

This study addresses the durability and performance challenges in Proton Exchange Membrane Fuel Cell (PEMFC) technology, primarily focusing on optimal humidity management. Acknowledging that, beyond technical aspects, the broader commercialization of PEMFCs is critically influenced by factors such as the cost and availability of hydrogen, this research aims to provide a comprehensive solution to enhance PEMFC applicability. Utilizing Nafion (NR-212), reverse osmosis (RO), and pervaporation (PV) membranes, the study optimizes five key performance metrics: pressure drop (∆P), dew point approach temperature (DPAT), water recovery ratio (WRR), Water Flux (J), and coefficient of performance (COP). These optimizations are conducted considering variables like temperature, humidity, flowrate, and membrane material. A deep neural network (DNN) model, incorporating Bayesian surrogacy with Gaussian process, gradient boost regression trees, and random forest, is developed using experimental data. With a correlation coefficient of 0.986, the model demonstrates high accuracy in predicting performance metrics, subsequently guiding genetic algorithms for effective PEMFC humidity control. The results show significant improvements in all metrics, with optimal values achieved for NR-212, RO, and PV membranes. This study thus presents a novel, practical deep learning approach, considering both technological advancements and external economic factors, for enhancing PEMFC operations.

Cellulose acetate (CA) mixed-matrix membranes incorporating polyvinylpyrrolidone (PVP), bentonite (B or Ben), graphene oxide (GO), and titanium dioxide (TiO2) were prepared by the phase inversion separation technique for oil/water separation. An investigation was performed where the mixed-matrix membrane was tested for the separation performance of hydrophilic and hydrophobic surface properties. An ultrafiltration experiment at the laboratory scale was used to test dead-end ultrafiltration models developed for the treatment performances of oily wastewater under dynamic full-scale operating conditions. Artificial oily wastewater solutions were prepared from hexane, toluene, and engine oil with Tween80 emulsions for oil removal treatment using composite membranes. The impacts of material hydrophilicity, weight loss, permeability, and pore size were investigated, and it was found that the oil retention of membranes with larger pore sizes enabled much more sophisticated water flux. The CA-GO-, CA-B-, and CA-TiO2-incorporated membranes achieved pure water flux (PWF) values of 45.19, 53.41, and 100.25 L/m2h, respectively. The performance of CA-TiO2 in oil/water emulsion rejection was assessed, and the rejection of engine oil/water, toluene/water, and hexane/water mixtures was determined to be 95.21%, 90.33%, and 92.4%, respectively. The CA-based mixed-matrix membrane portrayed better antifouling properties due to enhanced hydrophilicity and water molecules. The CA-TiO2-incorporated membrane possessed the potential to provide high separation efficiency for oily wastewater treatment. This study demonstrates the potential of fine-tuning membrane performances through material hybridization to achieve efficient wastewater treatment.

The effects of Constant current-Constant voltage charging and combined sinusoidal waveform charging methods on the internal structure of LiFePO4 battery have been discussed in detail in this study. Experimental results clearly indicated that after 600 cycles, the battery that utilized the charging method had retained about 94% of state of health. In the electrochemical impedance analysis and cyclic voltammetry tests, the portion of the SEI film impedance was increased about 0.08 mΩ. In the micro structured view, no significant SEI film formation was observed on the surface of the negative electrode that used the battery in the present charging method. Finally, in the analysis of the SEI film composition, it was found that the Li2CO3 and Li2O content in the Li element was only about 15.97% and 4.42% in the battery employing this charging method, and the battery component contents in the CC-CV charging method were 27.2% and 6.69% respectively.

BackgroundLithium-ion batteries are globally prominent and extensively employed alternative energy sources with decisive applications. In depth understanding of influences of various charging and discharging cycles on electrode materials and life span of these batteries is critical as cycle-life and safety of lithium-ion batteries are closely related crystallinity of electrode materials. This study is a detailed investigation endeavor in observing the degree of damage to electrode materials under multiple charging and discharging cycles.Methodology: A constant current-sinusoidal reflex charging method (CC-Sinusoidal) was implemented to charge commercial cathode Lithium cobalt oxide (LiCoO2) electrodes and anode graphite electrodes in comparison to the conventional charging method of constant current-constant voltage (CC-CV). After 100, 300, and 500 cycles of charging and discharging, EIS, SEM, XRD, and Raman spectroscopies were used to compare the degree of electrode damage caused by different charging methods.Significant outcomesThe structure of positive LiCoO2 electrode of the battery was observed to be stable, with no significant change in both the charging methods after 500 cycles. The use of CC-CV charging method had caused severe damages to graphite electrode with generation of solid electrolyte interface (SEI) films. The CC-Sinusoidal charging method had maintained the electrode material in a relatively ideal state.

Although current EU regulations, such as EU Directive 2015/1189 on the eco-design of solid fuel boilers and Directive 2015/1188, in accordance with the Machinery Directive 2006/42/EC, require manufacturers to meet specific emission requirements for CE marking, the routine and regular onsite testing of household heating appliances is still not mandatory in many EU countries. This research endeavour addressed this gap by evaluating the effectiveness of the Bacharach method as a rapid and cost-effective tool for assessing flue gas quality, particularly in terms of particulate matter mass concentration. This study also compared the results of the Bacharach method with those obtained from two commercially available portable analysers. The research outcomes demonstrate that the Bacharach method, in combination with an innovative evaluation approach, offers a viable solution, enabling the swift and economical assessment of flue gas quality with the primary objective of determining the boiler class according to the limits specified by standard EN 303-5 under operating conditions. The modified Bacharach method for measuring TSP in solid fuel-fired boilers provides qualitatively similar results to the commercially used SM500 and STM225 instruments. The modified Bacharach methodology was primarily developed for comparison to the boiler class 3 limit (i.e., 125 and 150 mg/m3). The study revealed that the modified Bacharach method, when applied to biomass-based boilers, exhibited higher accuracies in the case of classification into classes 3 and 4, whereas fossil fuel-based boilers demonstrated higher accuracy in the case of class 5 limits.

The possibilities of pistachio shell biochar production on laboratory-scale gasification and pyrolysis devices have been described by several previous studies. Nevertheless, the broader results of the pistachio shell co-gasification process on pilot-scale units have not yet been properly investigated or reported, especially regarding the detailed description of the biochar acquired during the routine operation. The biochar was analysed using several analytical techniques, such as ultimate and proximate analysis (62%wt of C), acid–base properties analysis (pH 9.52), Fourier-transform infrared spectroscopy (the presence of –OH bonds and identification of cellulose, hemicellulose and lignin), Raman spectroscopy (no determination of Id/Ig ratio due to high fluorescence), and nitrogen physisorption (specific surface 50.895 m2·g−1). X-ray fluorescence analysis exhibited the composition of the main compounds in the biochar ash (32.5%wt of Cl and 40.02%wt of Na2O). From the energy generation point of view, the lower heating value of the producer gas achieved 6.53 MJ·m−3 during the co-gasification. The relatively high lower heating value of the producer gas was mainly due to the significant volume fractions of CO (6.5%vol.), CH4 (14.2%vol.), and H2 (4.8 %vol.), while hot gas efficiency accomplished 89.6%.