Search Results (1,103)

Acorns (Quercus spp.) are an underutilized forest resource with recognized nutritional and bioactive potential, making them promising candidates for the development of sustainable plant-based functional foods. This study aimed to valorize acorns through the formulation of two novel acorn-based products, a plant-based beverage, and a pudding, and to assess their nutritional properties, sensory acceptability, and, for the beverage, refrigerated shelf-life stability. The beverage was optimized as a neutral-flavored milk alternative, using sodium alginate as a natural clean-label stabilizer to enhance emulsion stability and physicochemical properties. The final formulation exhibited low energy density and a lipid profile rich in monounsaturated fatty acids, contributing to its nutritional and functional value. Throughout 63 days of storage at 4 °C, sodium alginate effectively prevented phase separation and supported the retention of antioxidant capacity, as evidenced by stable ferric reducing antioxidant power (FRAP) and total phenolic content, although ABTS radical scavenging activity declined over time. No microbial growth was detected during storage, confirming the adequacy of the applied thermal treatment and aseptic filling procedures applied. The acorn-based pudding, developed by adapting a traditional egg-based recipe, functioned as a proof of concept illustrating the technological versatility of acorns across distinct plant-based matrices, exhibiting a nutritional profile comparable to commercial counterparts and high consumer acceptability. Overall, this work demonstrates the technological feasibility and versatility of incorporating acorns into plant-based food matrices, supporting their potential as sustainable ingredients for the development of innovative value-added foods and contributing to the valorization of forest resources. Full article

Biochar production from lignocellulosic waste represents a sustainable route for biomass valorization and carbon management within circular bioeconomy frameworks. In this study, biochar was produced from two abundant agricultural wastes in Türkiye—tea-brewing residues and almond husks—via controlled non-isothermal pyrolysis, and biochar yield was modeled using data-driven machine learning approaches. The effects of key process parameters, including carbonization temperature (37–850 °C covering drying/pre-pyrolysis and pyrolysis regions), residence time (1–150 min), and heating rate (10–60 °C min⁻¹), were evaluated using regression-based, ensemble, and deep learning models. Model performance was evaluated using cross-validation on training and testing datasets. The results showed that linear models exhibited limited predictive capability (R² < 0.95), while regularized and ensemble models improved performance (R² ≈ 0.97–0.99). Among all approaches, Gaussian Process Regression (GPR) achieved the highest predictive performance (R² ≈ 0.99, RMSE ≈ 0.06), indicating its superior ability to capture nonlinear relationships, particularly for limited datasets. Sensitivity and partial dependence analyses identified carbonization temperature as the dominant factor controlling biochar yield, with sharp declines observed above 600 °C. Optimal yields of 52–55% were obtained at 400–500 °C and residence times of 10–15 min, while lower heating rates enhanced yield stability. Overall, the results demonstrate that advanced machine learning models provide reliable tools for optimizing biochar production and supporting sustainable thermochemical conversion of lignocellulosic waste for energy and carbon-oriented sustainability applications. Full article

The pollution of water, including salt and fresh water, has become an emergency problem. Pollutants come from different sources and have various characteristics, starting from industry and fertilizers used in agriculture, sewage related to human living, and other sources. Diverse sources of pollution require a comprehensive approach to water purification. One possible approach may be the use of appropriate sorbents. Currently, one of the most promising materials used is zeolites. This is because they can come from various sources, including waste raw materials such as fly ash, and, therefore, allow for the use of a circular economy approach. Moreover, these materials can be modified, which enables their selective use for selected types of pollutants. Eventually, these materials become economically viable options. The main aim of this article is to present and analyze possible solutions to water pollution based on zeolite materials. For this purpose, a critical literature review was prepared. The review reveals that zeolites perform particularly well in ion-exchange-driven removal of inorganic contaminants, while their effectiveness for organic micropollutants under realistic conditions is often limited. The identified trade-offs between removal efficiency, regeneration stability, and scalability indicate that zeolites are best applied as function-specific rather than universal sorbents. From a sustainability perspective, this targeted applicability is supported by advantages, such as low material cost, long service life, and the possibility of using naturally occurring or waste-derived precursors, which, together, enable resource-efficient water treatment processes, reduced reliance on energy-intensive technologies, and the valorization of industrial byproducts within circular economy frameworks. Full article

Spent mushroom substrate (SMS), the main by-product of mushroom production, is rich in valuable compounds that could be recovered by ultrasound-assisted extraction (UAE) and exploited as fat-mimetic functional ingredients in food formulations. In this study, low-fat cookie prototypes were developed by incorporating a dietary fiber extract obtained from SMS using UAE. The extraction process was optimized following a Box–Behnken experimental design, identifying optimal conditions at a specific energy input of 200 J/mL, a particle size of 2 mm, and a solvent-to-solute ratio of 27%, yielding a dietary fiber recovery of 30.82%. The optimized SMS extract exhibited high oil-holding capacity (OHC) (1.39 g/g), emulsion stability (ES) (80%), and foaming capacity (FC) (83.55%). Four cookie formulations were evaluated, among which G1 (50% fat replacement) showed the best balance between consumer acceptability and an improved nutritional profile, characterized by higher protein (8.4 g/100 g), total dietary fiber (TDF) (7.10 g/100 g), and mineral contents. Notably, G1 cookies displayed a significant reduction in predicted glycemic index (pGI), decreasing from 83.84 in the control to 69.65. Overall, these results demonstrate that optimized SMS-derived dietary fiber is an effective functional ingredient for the development of low-fat, high-fiber, and reduced-glycemic cookies, contributing to the valorization of agro-industrial by-products within a circular economy framework. Full article

Coal gasification fine ash (CGFA) is a carbon–mineral composite solid waste whose valorization is severely hindered by poor interfacial compatibility with organic media due to its highly polar surface. Here, we report a surface alkylation strategy using haloalkanes with variable chain lengths to systematically tune the surface chemistry and thermo-oxidative behavior of CGFA. Comprehensive spectroscopic characterizations (XPS, FTIR, and ¹³C NMR) confirm successful grafting of alkyl chains, which increases aliphatic C-H content from 24.8% to 43.9% while reducing polar carboxyl groups from 7.9% to 1.6%, with the mineral framework remaining intact. Thermogravimetric analysis reveals that alkylation lowers the onset decomposition temperature from 358 °C to 295 °C and enhances the maximum mass-loss rate. Kinetic analysis shows that grafted alkyl chains act as low-energy initiation sites, reducing the initial activation energy to 95 kJ/mol, while the later-stage oxidation becomes diffusion-limited. Notably, long straight-chain alkylation achieves the best performance, whereas branched chains are less effective due to steric hindrance and pore blockage. This work establishes a clear chain-length-dependent structure–thermal response relationship, positioning alkylated CGFA as a designable precursor for functional carbon materials, intelligent char-forming agents, and tunable components for energy or responsive material systems. Full article

The oil palm production chain generates coproducts whose sustainable valorization remains a challenge. This study tested the hypothesis that partial replacement of the conventional substrate with oil palm coproducts could maintain the productive performance of Zophobas atratus larvae and generate value-added biomass. Mesocarp fiber (MF), palm oil mill effluent (POME), and palm kernel cake (PKC) were characterized in terms of physicochemical composition, carotenoids, and antioxidant capacity and examined as partial substitutes for wheat bran in six diets for Z. atratus. PKC demonstrated higher levels of protein (15.27%), carbohydrates (65.68%), neutral detergent fiber (68.35%), acid detergent fiber (37.70%), and saturated fatty acids (83.06%) and greater antioxidant capacity associated with phenolic compounds. MF showed the highest carotenoid content (138.27 mg/100 g), and POME had the highest lipid content (17.69%). Diet containing 50% PKC-supplemented wheat bran promoted higher feed conversion efficiency (78.99%), lower feed conversion ratio (0.90%), and higher larval protein content (39.14%) and maintained performance similar to that of the control. Larvae fed on 50% MF exhibited carotenoid bioaccumulation, with >190% increase compared with the control. Although the coproducts demonstrate potential as substrates, mortality restricts their technical feasibility. Their use depends on an adequate protein/energy balance and the digestibility of the fibrous fraction for strategic supplementation. Full article

The atypical proliferation of Sargassum (Sargassum spp.) in the tropical Atlantic and the Caribbean Sea over the past decade has triggered an unprecedented environmental and socioeconomic crisis along the Mexican coastline. Continuous beaching events of this macroalga on the Riviera Maya have caused coastal ecosystem degradation, severe impacts on the tourism sector, toxic gas emissions during decomposition, and high cleanup costs. To address this challenge, the valorization of Sargassum as a raw material for synthesizing functional materials represents a sustainable management strategy. In this study, a superabsorbent hydrogel was developed from Sargassum biomass (collected in Cancún, Quintana Roo, in 2025) using an innovative process that bypasses the conventional cellulose isolation step. The biomass was subjected to high-energy milling (15 and 30 min) to prepare Sargassum powder, which was subsequently carboxymethylated using monochloroacetic acid. This modified biomass was then crosslinked with citric acid, a process evaluated at three different citric acid/carboxymethylated Sargassum mass ratios. The hydrogel synthesized with the lowest crosslinking agent ratio achieved a maximum water absorption capacity of 1160 wt%, a value that exceeds the typical absorption capacities of 700–900% for biopolymer hydrogels. Successful material formation was confirmed by Fourier transform infrared spectroscopy (FTIR), which revealed the characteristic functional groups of CMC and the ester bonds formed during crosslinking. Additionally, scanning electron microscopy (SEM) analysis showed a well-defined porous structure with pore sizes ranging from 8.5 to 19.5 µm, which is essential for its high absorption performance. This study demonstrates the feasibility of producing high performance hydrogels from Sargassum through a simplified, cost-effective, and environmentally friendly process. These findings open a promising avenue for the integrated management of this problematic biomass, transforming it into value-added materials with potential applications in agriculture, hygiene, and environmental remediation. Full article

Avocados produced in Colombia’s Caribbean region represent a biomass with high potential for valorization beyond fresh consumption, particularly when their fractions are exploited as sources of value-added compounds. This study proposes a dual-production system integrating oil extraction from the pulp and biochar generation from the seed under a process approach aimed at maximizing raw material utilization. The process performance was evaluated through the application of the Extended Water–Energy–Product (E-WEP) methodology, which allows for a comprehensive assessment of water, energy, and material consumption, as well as product generation efficiency, based on computer simulation results. The findings indicate an overall process yield of 14.20%, limited by the high raw material demand, although a high oil recovery efficiency of 83.95% was achieved. Water consumption reached 17.84 m³/t, with 99.25% converted into wastewater, highlighting the need for improved water management strategies. The process exhibited an energy demand of 3613.19 MJ/h, predominantly covered by natural gas consumption, which led to an energy intensity of 23,192.65 MJ/t. Furthermore, the obtained NER and EUI values of 0.53 and 2.84, respectively, suggest that the system does not operate under energy self-sufficiency conditions. Nevertheless, the resulting products still present considerable potential for energy recovery and subsequent valorization processes. Full article

Hybrid hydrogen energy storage systems are increasingly considered for renewable integration in rural and weak-grid contexts, yet much of the literature remains simulation-based, site-specific, or insufficiently explicit about control and operational performance. This paper examines a hybrid hydro–PV–battery–hydrogen system operated at the Agkistron Living Lab in Northern Greece and assesses the role of layered storage in renewable surplus valorization and resilience-oriented operation. This study combines a system architecture description, a supervisory energy management strategy based on Hybrid Automata, and analysis of field data under both grid-connected and intentional off-grid conditions. The installation integrates hydropower, photovoltaics, battery storage, alkaline electrolysis, hydrogen storage, and PEMFCs. The results show that during on-grid operation, the EMS prioritizes battery charging and then hydrogen production, enabling high renewable utilization and low curtailment while preparing reserves for outages. During a 48 h intentional islanding event, the battery and hydrogen pathway operated sequentially, achieving an autonomy index of 82%, compared with 36% for the battery-only benchmark. Although the hydrogen pathway showed lower round-trip efficiency than battery-only storage, it substantially extended off-grid autonomy and continuity of supply. The findings support hybrid battery–hydrogen storage as a transferable operating concept for rural systems where renewable surplus and resilience requirements coexist. Full article

The functional valorization of waste fabrics, particularly their conversion into flexible low-cost, high-performance electrodes, holds significant promise for resource sustainability and the development of advanced energy technologies. Here, a NiB/Cu/polyester fabric (PF) composite electrode was fabricated via two-step electroless plating on waste PF and was demonstrated as a bifunctional electrocatalyst for methanol oxidation (MOR) and urea oxidation (UOR). The morphology, crystal structure, surface chemical state, and wettability of the electrodes were characterized using SEM, TEM, XRD, XPS, and contact angle measurements. The Cu interlayer critically enhanced interfacial wettability, intrinsic catalytic activity and stability. At 0.8 V, the NiB/Cu/PF electrode delivered average current densities of 312 mA·cm⁻² for MOR and 288 mA·cm⁻² for UOR, outperforming NiB/PF by 27.9% and 9.1%, respectively. After 2000 accelerated degradation cycles with electrolyte renewal, MOR and UOR activities were retained at 91.6% and 105.0%, respectively. Remarkably, the Cu interlayer conferred exceptional mechanical–electrochemical robustness: following 100 sequential bending and twisting deformations, current density retention ranged from 84.6% to 96.7% across multiple test configurations. The Cu interlayer acted as a flexible stress buffer during mechanical deformation, effectively improving the adhesion between the coating and the substrate. Full article

This study presents an integrated catalytic system enabling the quantitative production of 2,5-diethoxymethylfuran from HMF through a hybrid sequence that combines Ru-PNP-catalyzed hydrogenation with heterogeneous acid-catalyzed etherification in ethanol. The approach provides complete selectivity under mild conditions and demonstrates the compatibility of homogeneous hydrogenation catalysts with solid acid co-catalysts in a single process environment. In addition, we report the first example of homogeneously catalyzed hydrogenative valorization of HMF employing a co-catalytic, potentially recyclable acid additive. This strategy expands the scope of HMF upgrading pathways and highlights the potential of hybrid catalytic systems for the efficient synthesis of stable, energy-dense furan derivatives relevant to biofuel and biobased chemical applications. Full article

The integration of catalytic methane decomposition (CMD) with CO₂ gasification (Reverse Boudouard Reaction) offers a promising chemical looping route for carbon-negative hydrogen and syngas production. This work systematically investigates the gasification reactivity of six carbon morphologies, CNTs, CNFs, activated carbon, graphite, graphene, and CMD-derived carbon, with and without Ni addition. First, activity tests and characterization (XRD, XPS, Raman) revealed that CMD-derived carbon outperformed all other benchmarks due to its highly amorphous nature (sp³/sp² = 0.98), which provides a high density of reactive sites. Second, kinetic analysis showed that the incorporation of 5 wt% Ni on CMD carbon reduced the activation energy (E_a) from 435.3 kJ mol⁻¹ to 114.6 kJ/mol, the lowest among all samples. This 74% reduction confirms that structural defects in CMD carbon act as anchoring sites for Ni, facilitating a strong metal–support interaction (MSI) that promotes CO₂ activation. Third, an investigation into structural synergy revealed that higher Ni loadings (>5 wt%) increased the activation energy (up to 171.2 kJ mol⁻¹). This trend is attributed to Ni agglomeration and weakened MSI, which reduces the active catalytic interface. These findings demonstrate that the efficiency of CO₂ valorization is highly sensitive to carbon morphology, providing a clear optimization strategy for integrated chemical looping methane-to-syngas energy cycles. Full article

The Colombian Caribbean is a strategic area for avocado production, not only because of its favorable climatic conditions, but also because of the availability of varieties with a high content of compounds of industrial interest. The Creole-Antillean avocado grown in Montes de María represents a significant source of raw material with potential for processing, both because of the lipid fraction of its pulp and the chemical composition of its seed. However, the use of this resource has been limited by low technology incorporation and poor coordination of agro-industrial chains that would allow its valorization beyond fresh consumption. In view of this situation, the design of a plant for the simultaneous production of oil and biochar is proposed, with the aim of migrating from a linear model to a comprehensive biomass valorization scheme. The study analyzes the performance of the process from a thermodynamic perspective, applying an exergy analysis that allows for the evaluation of the quality of the energy used and the quantification of irreversibilities at each stage. The results indicate that the highest exergy destruction occurs during seed washing (12.37%), oil extraction and centrifugation (19.71%), distillation and condensation (20.64%), and pyrolysis with by-product separation (28.72%). Although the seed washing stage showed high exergy efficiency (99.81%) when integrated into biochar production, stage 12 recorded a significant loss of 2438.52 MJ/h, associated with the non-use of the volatile gases generated in pyrolysis. Overall, the exergy efficiency of the system reached 30.07%, reflecting the high thermodynamic demands involved in transforming the seed into a high-value product such as biochar. This type of assessment not only identifies critical points of exergy destruction, but also establishes technical bases for optimizing energy consumption, reducing losses, and moving towards a more efficient and sustainable process. Full article

The pulping and paper-making (P&P) industry is one of the world’s largest manufacturing sectors, yet it is plagued by high water/energy consumption and massive discharge of highly polluted wastewater. The effluents from pulping, bleaching and papermaking processes are characterized by high chemical oxygen demand (COD), intense color, toxic adsorbable organohalides (AOX) and abundant refractory lignin, which pose significant threats to aquatic ecology and human health. Although conventional physical, chemical and biological treatments have been widely applied, they are constrained by insufficient degradation efficiency toward recalcitrant organics, high cost and potential secondary pollution. In recent years, electrocatalytic technologies including electrocatalytic oxidation, electroreduction and their integrated processes, have demonstrated superior efficacy in specific scenarios of P&P wastewater treatment, such as lignin degradation, toxic side-streams treatment, pretreatment for enhancing biodegradability, and polishing steps in integrated treatment systems, which are not universally applicable solutions for P&P wastewater remediation. Meanwhile, biomass fuel cells typified by direct biomass fuel cells (DBFC) and microbial fuel cells (MFC) provide promising pathways for synchronous pollutant removal, energy production and resource recovery. Representative studies have reported COD removal efficiencies of 60–100% for electrochemical and advanced oxidation processes, while integrated electro-Fenton–biological treatment increased the BOD/COD ratio from 0.34 to 0.52 and achieved an overall COD removal of 94%. It should be noted that these advanced electrochemical technologies are still confronted with challenges in industrial scale-up, high energy and electrode material costs, and stable continuous operation. This review systematically elaborates on the physicochemical properties, generation mechanisms and environmental impacts of P&P wastewater, comprehensively summarizes the mainstream treatment technologies including physicochemical, biological, electrochemical and integrated processes, and analyzes their reaction mechanisms, efficiencies and applicable conditions. Particular emphasis is placed on electrocatalytic treatment and bio-electrochemical valorization strategies. This review is anticipated to provide a valuable reference for the efficient and targeted treatment as well as sustainable utilization of P&P wastewater, thereby supporting the green and low-carbon development of the P&P industry. Full article

Lignocellulosic wastes are low-carbon, renewable and sustainable feedstocks for replacing fossil fuels in the production of energy and chemical products. However, the bioconversion of lignocellulose into biofuels or biochemicals is costly. To address the high cost, this study extracted essential oil (EO) from ginger stalks and leaves (GSL) as an antioxidant to valorize the bioconversion process of GSL. The Box–Behnken design was used to optimize EO extraction, and the maximum EO yield of 2.99% was obtained under the optimal condition of KOH infiltration for 26 h, extraction for 3 h, and an n-hexane-to-GSL ratio of 8 (v/w). With 95% n-hexane recovery and no generation of waste liquid during the extraction process, fugitive emissions and solvent waste were reduced, enhancing sustainability. The EO’s antioxidant activity exceeded that of commercial ginger EO. The combined process of KOH infiltration and n-hexane extraction induced physicochemical changes in GSL and improved its enzymatic hydrolysis efficiency from 2.70% to 69.09%. According to the economic assessment, the bioconversion of GSL into bioethanol would benefit from the EO product, with the on-site production cost of cellulase being no more than 0.98 USD/kg. This study presents a feasible and sustainable case for lignocellulosic biorefining. Full article