Integrated biotechnological strategies combining Dark Fermentation (DF) and Anaerobic Digestion (AD) are gaining attention for sustainable waste management and energy recovery. This study focuses on the valorization of Construction and Demolition Waste (CDW), particularly the asbestos-containing fraction (ACW). The objectives areas follows: (i) the denaturation of chrysotile fibers via bioleaching using volatile fatty acids (VFAs) produced through DF, (ii) the conversion of DF supernatants into biomethane through AD, and (iii) the reuse of residual biomass to enhance process circularity.

DF involves several metabolic pathways, including acetate, butyrate, lactate, ethanol, and propionate fermentation (Sekoai et al., 2021), with acetate and butyrate dominating under mesophilic and thermophilic conditions. The fermentation is influenced by operational parameters such as pH, temperature, and food-to-microorganism (F/M) ratio (Pandey et al., 2022). DF at 35 °C led to the accumulation of 6.3 g/L butyric acid and 1.9 g/L lactic acid, while at 55 °C, lactic acid increased to 4.6 g/L. Other by-products such as ethanol and formic acid ranged from 0.5–1.5 g/L.

To stabilize the VFA-rich effluents, a second-stage AD process was carried out on three DF supernatants (S1, S2, S3) and their mixture (Smix, 1:1:1). Net methane yields ranged from 186 mL (S1) to 341 mL (S3). AD of Smix produced 259 mL CH₄ and 103 mL CO₂, with a methane yield of 0.38 L CH₄ g⁻¹ COD (Yeshanew et al., 2016). The complete process generated 4.9 L bio-H₂ and 19.7 L bio-CH₄ from 1.5 L of DF effluent (COD: 33.7 g/L).

Residual sludge (10.1 g TSS; 67.3% VSS) could be reused as inoculum, although periodic removal is required due to silica accumulation.

This integrated DF–AD system represents a sustainable route for converting hazardous ACW into valuable bioenergy, contributing to circular economy goals and EU environmental directives.

Experimental design is utilized to detect the effect of parameters on the process of hydrogen production. Thanks to experimental design methods, time and money consumption can be decreased. In addition to that, decreasing hazardous solvent and chemical consumption is crucial to the green chemistry approach. Regarding the synthesis of MOFs, solvents like methanol and expensive chemicals like imidazole salt are needed. In addition to that, after MOF synthesis, there are many more steps, like collecting crystals and drying them. Analysis of covariance (ANCOVA) is one of the experimental design tools. ANCOVA is formed from the fusion of two statistical methods, which are analysis of variance (ANOVA) and regression analysis. For this analysis, it is necessary to select one independent variable as a factor. At this time, other independent variables are called covariates. ANCOVA can be applied in various fields like medicine, agriculture, biology, and engineering. For the reaction producing H₂ from NaBH₄ hydrolysis, the researchers used response surface methodology (RSM) and ANOVA. To the best of the authors' knowledge, there is scarce research about the optimization of H₂ production from the NaBH4 hydrolysis reaction with ANCOVA. This study aimed to determine the effect of several parameters (catalyst amount, time, reactant amount) on hydrogen yield from NaBH₄ hydrolysis on several MOFs used in the literature.

Achieving climate change mitigation requires precise assessment of agricultural greenhouse gas (GHG) emissions. Although animal husbandry, soil management, and manure systems primarily address emissions generated directly on farms, hidden or unaccounted emissions remain largely unregulated. Agricultural and rural operations produce significant carbon emissions through indirect activities beyond farm boundaries. This review investigates major sources of greenhouse gas emissions linked to agricultural activities. Agricultural input production and transportation emissions, post-harvest storage and distribution losses, rural development infrastructure emissions, degraded land microbiological activity, and poorly managed or abandoned facilities fall under this category This study examines scientific and administrative challenges to evaluating these emissions. The major challenges include inadequate monitoring systems, unclear accountability, and dispersed rural emission sources. New technological tools, such as satellite-based carbon tracking, remote sensing of soil carbon changes, and machine learning techniques for emission detection will improve monitoring and measurement effectiveness. Mitigation approaches involve implementing full-chain life cycle assessments (LCAs), adapting sustainability frameworks to cover farm and post-farm stages, and developing policy tools that encourage emission management across the agricultural supply chain. Agriculture's environmental impact can be more precisely assessed by including these overlooked sources in greenhouse gas inventories. Adopting holistic approaches helps in crafting effective climate policies, enhancing sustainability certification systems, and empowering farmers, researchers, and policymakers to actively contribute to emission reduction. This study concludes that agricultural and rural greenhouse gas emissions evaluation studies should incorporate cross-disciplinary research methods and scalable technologies.

The evolution of wastewater treatment technologies is increasingly oriented toward hybrid solutions that combine treatment efficiency, economic sustainability, and operational simplicity. In this context, this study proposes an innovative approach based on an integrated bioreactor called eSFDMBR (electro Self-Forming Dynamic Membrane Bioreactor), which combines self-forming dynamic membranes (SFDMs) with electrochemical processes.

The system treats real wastewater of civil origin with variable loads. At its core is a membrane made of a highly porous fibrous support, on which a filtering layer forms naturally through particle deposition. Internal electrodes generate redox reactions that enhance pollutant removal, inhibit biofilm formation, and limit fouling.

Results showed performance superior to traditional MBR (Membrane Bioreactor) systems. The removal efficiencies obtained in this innovative system were higher by more than four percentage points for COD (Chemical Oxygen Demand) removal, by approximately forty percentage points for NH₄-N (Ammonium Nitrogen) removal, and by more than fifty percentage points for PO₄-P (Orthophosphate) removal.
The system maintained stability despite variations in load and temperature, demonstrating remarkable operational resilience.

Fouling control, one of the main limitations of MBRs, was effectively addressed through electrochemical action, which significantly reduced the presence of EPSs (Extracellular Polymeric Substances) and SMPs (Soluble Microbial Products). This ensured stable transmembrane pressure and reduced the need for cleaning interventions.

From an economic and management perspective, the use of low-cost membrane materials, combined with the process efficiency, leads to lower costs compared to conventional membrane systems. Moreover, the reactor’s simple design and operational flexibility make it suitable for decentralized contexts.

In summary, the eSFDMBR represents a promising solution for more sustainable and efficient wastewater treatment.

Scarcity of water is still the most critical issue facing the world today. It is further compounded by high population growth, pollution, and climate change. Traditional means of desalination are effective but tend to be energy-intensive, resource-expensive, and environmentally demanding. This research explores a novel, environmentally friendly method of seawater desalination in the creation of low-cost biofilters made from crop waste. Banana plant stems and orange peels were transformed into powdered and activated carbon forms and blended into polyurethane foam matrices to achieve bioadsorptive filters. The materials were examined through pH analysis, granulometry, ash content, zeta potential, and FTIR spectroscopy to identify their physicochemical properties. Experimental tests yielded impressive improvements in adsorption capacity, with orange-peel-filter-activated samples recording a 31.5% particle size reduction and up to 72% removal of copper (Cu²⁺) and 68% removal of cadmium (Cd²⁺) under optimized conditions. A portable appliance, the "Magique Cup," was also introduced in this study, which can be applied in homes for water treatment using filters. Regeneration tests also indicated that up to 85% of the original adsorption capacity could be recovered through acid or heat treatment. The findings show the potential of biodegradable, waste-derived biofilters to provide successful alternatives to traditional desalination processes. Scaling of the technology, long-term filter stability, and field-operating performance should be tackled in subsequent research.

Thermoelectrics enable the direct conversion of heat into electricity and vice versa without any moving parts. This technology is particularly valuable for recovering waste heat from engines, industrial systems, or even body heat, helping to improve overall energy efficiency. CuGaTe₂ is a promising chalcopyrite compound for thermoelectric energy conversion. In this work, we investigate the effect of biaxial strain—both compressive and tensile—on its thermoelectric properties using density functional theory (DFT) implemented in Wien2K code combined with the semi-classical Boltzmann transport formalism. Biaxial deformation on the plane was simulated by modulating the c/a ratio while keeping the volume constant. We optimized structural parameters and electronic properties. After, we studied the thermoelectics parameters as a function of carrier concentration (p and n), and through these parameters we modelised a thermoelectric module and calculated its conversion efficiency as a function of the type and intensity of strain applied. Our first-principles calculations reveal a significant improvement in thermoelectric performance under moderate compressive strain of 4%, with noticeable enhancements in the figure of merit ZT (from 0.63 to 0.91), and the calculated conversion efficiency (from 4.7 % to 6.5% for a temperature difference of 75°C) . These findings highlight the potential of strain engineering as a viable strategy to optimize the electronic transport properties of CuGaTe₂ and similar chalcopyrite materials for high-efficiency thermoelectric applications.

Thermal comfort in urban environments is increasingly being addressed through smart, energy-efficient strategies, especially as cities adapt to rising temperatures and sustainability mandates. This study presents a systematic review of recent research on energy-saving methods for improving outdoor and semi-outdoor thermal comfort in smart cities. Articles were sourced from Scopus and Web of Science (2020–2025), and analyzed based on applied methods, effectiveness, and geographic distribution.
The reviewed literature highlights five main categories of strategies: (1) passive interventions (e.g., vegetation, phase change materials, reflective coatings), (2) smart materials (e.g., thermochromic windows and bioinspired textiles), (3) AI-driven HVAC and thermal control systems, (4) sensor-based human-centric feedback loops, and (5) integrated energy management systems (EMS) including residential energy hubs. China and the USA lead in research output, with significant contributions from Spain, India, and the Netherlands.
Reported effectiveness varies by method and context: passive solutions reduced MRT by 2–5°C and surface temperatures by up to 20°C; AI-based controls achieved HVAC energy savings of 20–30%; and thermochromic coatings lowered cooling demands by 10–25%. Despite technological advances, relatively few studies incorporate human thermal perception data or prioritize equity in thermal comfort distribution.
This review identifies key innovation trends and proposes a classification framework for energy-efficient thermal strategies in smart urban contexts. Future research should emphasize user-centered metrics, interdisciplinary integration, and implementation across varying climate zones, especially in vulnerable regions

The ever-growing global consumption of coffee generates millions of tons of spent coffee grounds (SCGs) annually, posing a significant waste disposal problem. While some SCGs find use in composting or biogas production, a large portion remains underutilized. This study introduces a novel circular waste-to-energy pathway to tackle this challenge. Our proposed technology employs a cascading valorization approach, utilizing non-catalytic supercritical transesterification of pyrolytic oil derived from SCGs for liquid hydrocarbon production. The process begins with pyrolysis, which converts SCGs into pyrolytic oil. This oil is then upgraded via supercritical transesterification with methanol. Experiments were conducted using a 1:6 oil-to-methanol ratio at precisely controlled conditions of 239.4°C and 1200 psi for 20 minutes. This optimized process yielded an impressive 96% of valuable liquid hydrocarbons. The resulting product exhibited highly favorable characteristics, including a density of 755.7 kg/m³, a viscosity of 0.7297 mm²/s, and a high heating value (HHV) of 48.86 MJ/kg. These properties are remarkably comparable to conventional biofuels and standard fossil fuels, demonstrating the product's potential as a viable energy source. These compelling results unequivocally demonstrate that non-catalytic supercritical transesterification effectively upgrades SCG-derived pyrolytic oil into valuable liquid hydrocarbons. This innovative approach offers a sustainable solution for SCG waste management, significantly contributes to a circular bioeconomy, and presents a promising alternative for renewable fuel production, thereby potentially reducing global reliance on fossil fuels.

The widespread disposal of pharmaceutical wastes, particularly diclofenac (DCF), poses a significant threat to aquatic ecosystems. The current degradation methods, including biological treatments and standalone advanced oxidation processes, often prove insufficient, leaving residual DCF concentrations. This study proposes a novel solution using a rapidly synthesized graphene oxide/hydroxyapatite (GO/HAp) nanocomposite via wet-chemical precipitation to enhance DCF degradation through synergistic sonophotocatalysis. The synthesized nanocomposite’s structure was confirmed using FTIR, XRD, and SEM analyses, revealing the successful formation of a hexagonal HAp phase on GO sheets. Optimization of the sonophotocatalytic parameters revealed that pH and loading significantly influenced degradation, while time had a less pronounced effect. The optimal conditions (a pH pf 4, 45 mg GO/HAp, 30 min) achieved a remarkable 93.86% DCF degradation, significantly outperforming standalone photocatalysis (72.76%) and sonolysis (63.76%). This enhanced performance is attributed to the synergistic effect of sonophotocatalysis, which increases the active surface area and radical generation, coupled with the high surface area and adsorption capacity of the GO/HAp nanocomposite. This research demonstrates that rapid wet-chemical synthesis of the GO/HAp nanocomposite, coupled with an optimized sonophotocatalytic process, offers a potent, accelerated, and efficient method for degrading DCF, paving the way for improved pharmaceutical wastewater treatment. Ultimately, this research provides a foundation for developing effective water treatment solutions to combat pharmaceutical contaminants.

The increase in global energy demand has led to a rise in interest in the use of heavy oil. However, the widespread use of petroleum hydrocarbons has resulted in considerable environmental issues. In this study, we aimed to observe the biodegradability of the heavy oil using microbial consortia derived from contaminated soil and water. We investigated the biodegradability of heavy oil under aerobic and anaerobic conditions over three weeks, and the residual percentage of heavy oil was estimated using gas chromatography analysis. Under aerobic conditions, soil microbial communities demonstrated a higher biodegradation rate of heavy oil than water microbiota. On the other hand, in anaerobic conditions, soil and water samples showed reduced biodegradation rates, and some major hydrocarbon peaks persisted, suggesting the presence of recalcitrant fractions such as PAHs (polycyclic aromatic hydrocarbons). However, this study also examined initial bacterial counts (colony-forming units, CFU) to assess its effect on the biodegradability of heavy oil. Although we did not observe a statistically significant correlation between initial CFU/ml and heavy oil biodegradation, we observed high levels of heavy oil biodegradation when the initial CFU/ml was high. In conclusion, this study is significant in the context of the potential to observe the degradability of heavy oil in natural environments under aerobic and anaerobic conditions, as well as the influence of microbial communities.