Search Results (1,162)

Anaerobic digestion (AD) is widely used for organic waste stabilization and bio-energy recovery, but its performance is often constrained by process instability, slow syntrophic metabolism, and sensitivity to acidification, ammonia, organic overloading, and inhibitory contaminants. Biochar has emerged as a promising strategy to enhance AD, with benefits extending beyond increased methane yield. This review examines how biochar properties, including pore structure, surface functional groups, alkalinity, and electrical conductivity, regulate different AD stages and improve process stability. Biochar provides microbial habitats, buffers pH, adsorbs inhibitors, accelerates volatile fatty acid conversion, and facilitates interspecies electron transfer. The effects of biochar dosage, feedstock type, reactor configuration, and operational conditions on digestion performance and resource recovery are critically evaluated. Broader contributions to organic waste valorization are also discussed. Future research should prioritize tailored biochar design, standardized characterization, long-term validation in continuous reactors, techno-economic analysis, and life-cycle assessment. These efforts are essential for translating laboratory findings into reliable and sustainable applications for organic solid waste treatment and resource recovery. Full article

The development of sustainable coatings that combine reprocessability with active functionalities remains a central challenge for the composites sector. In this work, a healable, electrically conductive coating was formulated using epoxidized castor oil (ECO) as a bio-based matrix, dibutyl phosphate (DBP) as a transesterification catalyst, and short recycled carbon fibres (RCFs, 2 mm in length) as a conductive filler at loadings of 10 and 20 phr. Formulations were UV-cured via cationic photopolymerization and characterized across the full liquid-to-solid processing chain. FT-IR and photo-DSC showed that increasing RCF content progressively reduced curing rate and conversion, an effect attributed to light scattering/absorption by the fibres and restricted chain mobility, although gel content remained above 98% in all cases. DMTA showed that RCF did significantly affect the glass transition temperature but markedly increased the rubbery storage modulus and apparent crosslink density, consistent with a physical reinforcement mechanism. Stress relaxation tests confirmed the dynamic bond exchange behaviour in all formulations, with the apparent activation energy decreasing from 112 kJ/mol for the neat resin to 33–34 kJ/mol upon RCF incorporation. This significant reduction suggests that the presence of RCF facilitates the bond-exchange process, potentially through interfacial interactions between the polymer network and the fibre surface. However, the specific molecular mechanism responsible for this effect cannot be established from the present data. Electrical conductivity peaked at 10 phr RCF (3.6 × 10⁻³ S/m), enabling measurable Joule heating, while the 20 phr formulation showed reduced conductivity linked to voids and lower conversion. Thermally triggered healing at 120 °C for 6 h restored mechanical integrity, which is higher than reference values, demonstrating the coating’s capacity for repeated repair through its dynamic covalent network. Full article

Postharvest spoilage of fresh fruits demands efficient bio-based packaging films. Here, chitosan/gelatin (CG) films were incorporated with β-cyclodextrin-encapsulated clove essential oil microcapsules (β-CD@CEO MCs) at varying loadings. The results suggested that CEO encapsulation occurred within β-CD cavities and hydrogen-bond binding of MCs to the CG matrix. At 0.4% MCs, the composite film showed 60.11% higher tensile strength, excellent UV shielding, lower water vapor transmission rate, and strong antioxidant activity (DPPH 89.6%, ABTS 97.1), along with 58.21% biodegradation after 16 days of soil burial. In vitro release studies revealed a pH-responsive sustained release profile of CEO from the composite films, with faster release under acidic conditions (98.5% at pH 3.5 after 72 h) compared to neutral conditions (87.2% at pH 7.0), indicating the potential for targeted release on the weakly acidic grape surface. The film also exhibited significant antimicrobial effects against Botrytis cinerea, Penicillium gladioli, Staphylococcus aureus, and Escherichia coli. In table grape preservation, CG/MCs-0.4 film effectively delayed decay, reduced weight loss by 38.79%, maintained firmness and color, and preserved higher levels of soluble solids, titratable acidity, reducing sugars, and vitamin C compared to polyethylene packaging and untreated controls. Full article

Global population growth, climatic extremes and rising resource pressures necessitate innovative agricultural methods to boost food, feed, fibre and fuel production sustainably. Seed enhancement technologies (SETs), such as seed coating and priming, have emerged as effective strategies to improve seed viability and vigour, seedling establishment and overall crop yield. Conventional seed treatments include seed coating (film coating, encrusting, pelleting) and seed priming (hydro-, osmo-, halo- bio-, nutri-, hormonal-, chemical- and solid matrix priming). They offer advantages such as improved seed handling, uniform germination and promotion of early growth. However, they also have significant drawbacks, including on soil health and off-target pollution from synthetic polymers and pesticides, seed longevity issues from re-drying and outcomes that can vary among different crops, soils and environments. To tackle these issues, new non-traditional SETs are being investigated, including nanotechnology, novel biodegradable coatings and agrichemical-free biostimulants, such as plant growth promoting microorganisms. These innovative methods demonstrate great promise in enhancing active and crop performance while minimising environmental impacts by providing alternatives to materials derived from fossil fuels and that contribute to waste and pollution. This review critically examines both conventional and novel SETs, discusses their pros and cons and outlines strategic research and industry directions to enhance agricultural sustainability and productivity in light of global food and resource security challenges. Full article

The development of sustainable adsorbents from industrial biowaste has become an important strategy for reducing the environmental impact of both solid waste generation and wastewater pollution. In this study, residual Saccharomyces pastorianus biomass recovered from the brewing industry was immobilized in a polymeric matrix and evaluated as a bio-composite for the removal of reactive dyes from aqueous media. Orange 16 was selected as the target molecule. Batch biosorption experiments were conducted to identify the optimum operating conditions and to determine the adsorption capacity through Langmuir isotherm analysis. The performance of the biosorbent was subsequently validated under continuous-flow conditions in a fluidized-bed reactor, where the effects of flow rate on column (3.8 and 8.5 mL/min) efficiency were investigated. Experimental breakthrough curves were analyzed using the Clark, Yan, Bohart–Adams, and Yoon–Nelson models, which adequately described the dynamic biosorption process, particularly at the lower flow rate. The best agreement was obtained at a flow rate of 3.8 mL/min, an initial dye concentration of 87 mg/L, and a biosorbent mass of 19.5 g. The developed bio-composite material exhibited efficient dye removal and stable operation, demonstrating that residual brewing biomass can be successfully transformed into a low-cost and sustainable biosorbent suitable for continuous treatment of reactive-dye-containing wastewaters. Full article

Modified atmosphere packaging (MAP) is a preservation and packaging technology used to extend the shelf life of foods and agricultural products, maintain quality stability, and ensure food safety. To systematically review and summarize the current research landscape, technical challenges, and development trends in the MAP field, this study selected 1568 publications related to MAP from the Web of Science Core Collection (WOSCC) database during 2016–2025 and conducted bibliometric and visualization analysis. The results indicate that research activity in the MAP field has remained robust over the past decade, mainly focusing on four research areas: atmosphere regulation and packaging system design; microbial ecology, safety, and spoilage control; physicochemical deterioration and quality regulation; functional packaging materials and integrated preservation technologies. Countries such as China, Italy, and Spain have demonstrated outstanding performance in terms of publication output and academic influence in the MAP field, forming a solid research foundation in the MAP of perishable foods such as fruit and vegetables, meat products, and aquatic products. Research in the MAP field has gradually shifted from the verification of application effects toward system design and mechanistic analysis. Active packaging, intelligent packaging, bio-based materials, natural functional ingredients, volatile organic compounds, microbial community succession, and quality deterioration mechanisms have gradually become research hotspots, indicating a trend toward precision, sustainability, and functionality. These findings may provide references for future research topic selection, innovative packaging system design, and the development of novel food preservation technologies in the MAP field for foods and agricultural products. Full article

Biorefineries that convert the organic fraction of municipal solid waste (OFMSW) into advanced biofuels can integrate waste management with renewable energy production. However, their environmental performance remains insufficiently characterised owing to a scarcity of life cycle assessment (LCA) studies based on real operational data. This study presents a gate-to-gate LCA of a demonstration biorefinery processing source-separated food waste into bio-oils, bioethanol, and biogas. The ReCiPe 2016 Midpoint (H) method was applied across 18 impact categories, with system expansion crediting the displacement of rapeseed oil, maize-derived ethanol, and marginal biogas-derived electricity. The net global warming potential (GWP) was 68.5 kg CO₂ eq per tonne of wet OFMSW (69% reduction from gross), placing the biorefinery 83–93% below landfilling, 63% below incineration with CHP, and above standalone anaerobic digestion systems that lack the energy-intensive drying and enzymatic hydrolysis steps of the present configuration. Bio-oil and bioethanol achieved net-negative GWP per kilogram of product (−0.89 and −0.66 kg CO₂ eq, respectively), whilst eleven of eighteen categories achieved net savings under system expansion. Enzyme production dominated the bioethanol environmental profile (37–94% across categories), whilst drying dominated bio-oil (46–93%). Monte Carlo simulation confirmed that the sign of the net impact stayed unchanged across the entire 95% confidence interval (the interval did not span zero) for 17 of 18 categories. Full article

The urgent need for bio-based functional materials has driven a shift away from fossil-fuel-sourced materials toward renewable lignocellulosic biomass (LCB). This comprehensive review explores the advancements in LCB carbonization between 2020 and 2026, marking a shift from traditional, low-yield combustion processes toward highly selective and sustainable thermochemical conversion pathways. The primary objective of this review is to evaluate the integration of green pretreatment strategies, conversion technologies, and efficient valorization of the aqueous effluents and by-products. The goal of green pretreatment is to overcome the inherent recalcitrance of LCB without the use of harsh chemicals and reaction conditions, specifically highlighting the effectiveness of deep eutectic solvents (DESs) and ionic liquids (ILs). The review also evaluates the emerging conversion technologies, including hydrothermal carbonization (HTC), microwave-assisted pyrolysis (MAP), and the synergistic co-pyrolysis of LCB with synthetic polymeric wastes. Another novel concept in preparing hard carbon and other related materials is the “lignin-first” biorefinery strategy, which facilitates the subsequent production of high-value aromatic monomers, platform chemicals, and biofuels. The engineered carbon materials are increasingly utilized well beyond their traditional use as solid fuels. The products have been proven to be excellent for use in high-performance energy conversion and storage, serving as renewable bio-based electrode materials for supercapacitors and carbon electrodes in next-generation batteries. Full article

Electrochemical treatment can provide contaminant destruction, phase separation, ionic polishing, and resource recovery; however, performance cannot be judged by removal efficiency alone. This structured critical review compares electro-oxidation (EO), electrocoagulation (EC), electro-Fenton (EF), electrodialysis (ED), electrodeionization (EDI), capacitive deionization (CDI), flow-electrode CDI (FCDI), and bioelectrochemical systems (BES) in municipal wastewater, industrial effluents, sludge-related applications, and treatment side-streams. Searches of Scopus, Web of Science Core Collection, and PubMed were updated to 22 July 2026, and the evidence was assessed according to treatment function, wastewater realism, operating mode, durability, residual fate, energy and cost boundaries, resource recovery, and life cycle implications. Recent advances include porous flow-through anodes, oxygen-efficient cathodes, selective ion separation materials, and pilot BES configurations. However, scale-up remains constrained by electrode aging, by-products, sludge and concentrate management, oxygen transfer, fouling, competing ions, internal resistance, biological instability, and incomplete long-term economic and environmental evidence. The quantitative results show that the energy, cost, and carbon outcomes depend strongly on the treatment function and system boundary. The evidence for sludge and biosolids is less mature than that for liquid wastewater. Therefore, electrochemical technologies are best positioned as function-specific units within hybrid treatment trains rather than as universal replacements for conventional treatments. Full article

Food waste (FW) valorization through resource recovery is central to circular economy strategies that reduce environmental burden while generating sustainable, bio-based chemicals. This work investigated the effect of anaerobic sludge inoculum and the process control parameters of temperature (35 °C and 55 °C), pH value (4–10), and total solids content (2.5%, 5%, 7.5% and 10%) on the recovery of volatile fatty acids (VFAs)—chemicals used in bioplastics and bioenergy production—during acidogenic fermentation of food waste in batch reactors. While FW is well studied for biogas production, its potential for VFA recovery, a strategy that adds economic value to waste streams and supports the circular bioeconomy, remains comparatively underexplored. Mesophilic conditions favored fermentation over thermophilic conditions, and pH was the most influential factor affecting VFA accumulation, although temperature, inoculum presence, and total solids content also had statistically significant, large effects. Basic pH values provided maximum VFA yields from 2% to 25%, roughly double the acidic pH yields, while the highest solids content (10%) minimized VFA production at both temperatures. The highest yield (25%) occurred at T = 35 °C, pH 9, and TS = 5%, without sludge, while the highest yield under thermophilic conditions (T = 55 °C) reached 22.4% at TS = 2.5% and pH 9. By systematically evaluating these parameters together, this study offers a more comprehensive understanding of FW acidogenic fermentation than prior single-parameter works, guiding bioprocess design for sustainable waste management and resource efficiency. Full article

Hydrothermal liquefaction (HTL) of lignocellulosic biomass produces multiple product fractions, including solid residue (SR), heavy bio-oil (HBO), aqueous phase (AP), and light bio-oil (LBO). This study mainly applied principal component analysis (PCA) and regression modeling to predict AP solution weight, LBO weight and fuel characteristics, and HTL wastewater biodegradability, as well as to improve prediction accuracy for SR and HBO under various operating conditions (temperature: 250–350 °C, residence time: 5–60 min, and the combined solid loading of three batches: 15–45 g). A complementary relationship between SR and AP weights found in PCA enabled the estimation of AP weight based on predicted SR values in a regression analysis. A modified partition coefficient was introduced to link LBO weight with the carbon content of AP and was predicted, enabling accurate LBO yield estimation. Although LBO fuel characteristics could not be modeled reliably, those of SR and HBO were predicted with improved accuracy over prior kinetic models. The concentration of catechol in HTL wastewater (HTL-WW) was also modeled from operating conditions and linked to half-maximal inhibitory concentration (IC₅₀) of R. jostii and A. niger as a biodegradability index. This work demonstrates the feasibility of predicting underrepresented HTL outputs using statistical approaches. Full article

This study provides the main performance estimates for new concepts, using flexible gasification operation modes, adaptable to prevailing market conditions, for the production of bio-synthetic natural gas (bio-SNG) and biochar from biogenic residues and waste, such as bark, straw, and Solid Recovered Fuel (SRF). Dedicated integrated process models were developed in Aspen Plus based on and validated against data from experimental campaigns in a gasification and gas cleaning pilot plant. Simulation runs show that the proposed concepts convert biomass to bio-SNG 10% more efficiently than the reference case, mainly due to the considerably reduced oxygen demand at the Autothermal Reformer (ATR) enabled by the improved catalyst. The co-production mode schemes showed promising results in terms of overall plant efficiency, at 76.5–78.2%, and total carbon utilisation, at 41–55.3%. The hybrid cases require an electrolyser with a power capacity almost 70% of the biomass thermal input to the gasifier, resulting in a total electricity consumption of up to 0.769 kWhe/kWh of biofuel. In return, they achieve over 50% utilisation of the carbon contained in the feedstock for biofuel production and a 70.1–76.5% total plant energy efficiency. Efficient biofuel and biochar production unlock negative emission potential, further strengthening the value of these flexible concepts. Full article

This study aimed to investigate the effects of thermo-mechanical treatment and solid-state fermentation (SSF) on the structural, physicochemical, and techno-functional characteristics of wheat bran (WB), with a particular emphasis on specific isolated protein fractions, starch, and dietary fibre. WB was subjected to extrusion at different temperatures (90, 115, and 130 °C) and screw speeds (16 and 25 rpm), followed by a 24-h SSF with Liquorilactobacillus uvarum. Changes in chemical composition, hydration properties (water absorption, solubility, swelling capacity), temperature-dependent (30–80 °C) extract viscosity, as well as protein extraction yields and in vitro protein digestibility of isolated protein fractions were systematically evaluated. Extrusion reduced insoluble dietary fibre (IDF) content by 15.7–33.9%, while increasing soluble dietary fibre (SDF) content by 59.1–94.2%, and SSF with L. uvarum additionally increased the SDF fraction by 6.5–7.9%. Regarding technological properties, extrusion increased WB water solubility (WS) up to 14.6%, and 24-h fermentation further enhanced WS, reaching up to 16.3%. Extrusion increased the degree of starch gelatinisation up to 49.1%, whereas fermentation reduced it to 40.7% and decreased the WB extract viscosity by 18.3–24.6%. Furthermore, 24-h SSF enhanced the in vitro digestibility of globulin, gliadin, and glutenin fractions from initial values of 71.3–78.8%, 70.6–75.2%, and 70.2–73.0% to 82.0–85.6%, 83.3–88.6%, and 79.4–89.0%, respectively. The observed thermo-induced thickening and enhanced digestibility suggest that modified wheat bran has potential as a functional bio-ingredient for future application in novel food formulations. Full article

Agro-industrial residues from livestock and sugarcane production—particularly abundant in regions such as Veracruz, Mexico, where both agro-industries co-occur in high density—constitute underutilized carbon and nitrogen streams with high potential for biotransformation within circular bioeconomy frameworks. This study aimed to evaluate whether inoculation with Lactobacillus delbrueckii subsp. bulgaricus SP96 at increasing levels (5, 10, and 15% v/v) achieves simultaneous stabilization, carbohydrate-to-lactic-acid conversion, and nutritional enrichment of a thermally pretreated bovine manure (BM)–agro-sugarcane waste (ASCW) mixture, and to describe the underlying growth kinetics using the Gompertz model. Thermal pretreatment reduced Salmonella spp. and fecal coliforms to levels compliant with NOM-004-SEMARNAT-2002 Class B biosolid standards, yielding a substrate with suitable fermentability (14.56 gL⁻¹ carbohydrates, 0.44% total nitrogen, pH 6.52, and 90.43% volatile solids). Fermentation at 37 °C and 120 rpm for 72 h followed Gompertz kinetics (R² = 0.92–0.97). The 15% inoculum achieved the highest conversion efficiency and product yield (lactic acid and carbohydrate consumption), whereas the 10% inoculum represented the most balanced operating condition (best kinetic fit, R² = 0.97). However, differences in lactic acid concentration among treatments were not statistically significant (p > 0.05). The resulting biomass showed high organic matter (93.45%), increased crude protein (8.5%), a C/N ratio of 39.9, and enrichment in P₂O₅, MgO, Na₂O, and B. These findings validate a low-cost, scalable platform for simultaneous waste stabilization and generation of value-added, protein-enriched biomass with potential application as a feed supplement and soil amendment, pending further safety and functional characterization, from agro-livestock residues. Full article

Waste-derived fertilising materials, including sewage sludge, compost, digestate, food-waste-derived products and commercial organic or organo-mineral fertilisers, return nutrients to farmland but can also transfer microplastics to agricultural soil. This critical review examines their occurrence across these streams, analytical constraints, fate after application and the EU regulatory framework. Reported abundances span orders of magnitude and cannot be pooled because extraction, polymer identification and reporting are not harmonised, while particle-counting and mass-based methods measure different quantities. Field evidence indicates topsoil retention and accumulation after repeated application, whereas crop transfer and field-scale ecological effects remain poorly quantified. Regulation (EU) 2019/1009 sets no microplastic-specific product limit. For compost qualifying as CMC 3 and digestate other than fresh crop digestate qualifying as CMC 5, it controls plastic impurities above 2 mm by mass, while smaller particles remain outside that criterion. Waste-derived fertilisers can therefore form a recurrent, incompletely regulated pathway for microplastic transfer to soil. Controlled studies demonstrate hazard potential for selected particles and exposure conditions, but the magnitude and likelihood of effects under field conditions remain uncertain. The immediate priority is harmonised monitoring and reporting of the sub-2 mm fraction, including a stated lower size limit, polymer-confirmed particle counts and minimum QA/QC. Full article