Search Results (1,879)

This study investigates the effect of 3-glycidoxypropyltrimethoxysilane (GPTMS) concentration on the mechanical, interfacial, and fracture behavior of epoxy/microfibrillated cellulose (MFC) composites derived from oil palm empty fruit bunch (OPEFB). GPTMS was incorporated at 1, 3, and 5 Phr to improve compatibility between hydrophilic MFC and the hydrophobic epoxy matrix. Mechanical testing revealed that GPTMS concentration significantly influenced composite performance in a concentration-dependent manner, with 1 Phr GPTMS providing the most balanced reinforcement. At this concentration, tensile strength increased by 14.5% from 32.88 ± 3.61 MPa to 37.65 ± 1.42 MPa, while flexural strength improved by 5.55% from 70.24 ± 5.30 MPa to 74.14 ± 4.10 MPa compared with the unmodified composite. Tensile modulus also increased from 2.07 ± 0.06 GPa to 2.21 ± 0.16 GPa, accompanied by improved flexural modulus from 2.39 ± 0.12 GPa to 2.47 ± 0.21 GPa. SEM analysis revealed that the optimized formulation promoted more uniform MFC dispersion, improved interfacial integrity, reduced void formation, and enhanced fracture resistance through tortuous crack propagation, localized radial crack branching, and matrix tearing. In contrast, higher GPTMS concentrations (3 and 5 Phr) reduced mechanical efficiency, with flexural strength declining to 65.27 ± 5.33 MPa and 66.16 ± 4.23 MPa, respectively, due to increased fiber pull-out, interfacial heterogeneity, and more continuous crack propagation. FTIR analysis suggested possible silane-related interfacial modifications consistent with GPTMS incorporation, although these findings are interpreted as supportive rather than definitive evidence of grafting. Overall, the results demonstrate that moderate GPTMS incorporation (1 Phr) is the optimum strategy for enhancing epoxy/MFC composite performance, offering a practical pathway for developing sustainable lightweight bio-based composites with balanced strength, stiffness, and fracture resistance. This research contributes to SDG 12 (Responsible Consumption and Production) by promoting sustainable utilization of oil palm biomass waste for advanced engineering materials. Full article

This study aims to systematically investigate the combined effect of chemical activation of açaí seeds (Euterpe oleracea Mart.), with an aqueous sodium hydroxide (NaOH) solution at 2 mol·L⁻¹, and process temperature by pyrolysis of alkaline activated açaí seeds on the yield of reaction products (bio-oil, gas, H₂O, and biochar), physicochemical properties (acid value, density, and kinematic viscosity) and chemical composition (hydrocarbons and oxygenates) of bio-oil. Catalytic pyrolysis was carried out in a 143 L reactor at temperatures of 350 °C, 400 °C, and 450 °C, 1.0 atmosphere, operating in batch mode. The NaOH activation played a crucial role in modifying the thermal degradation pathway of the biomass, promoting the formation of specific chemical structures and altering the product yields. NaOH acted as a catalyst, enhancing the deoxygenation of the biomass and stimulating the formation of hydrocarbons. As a result, the yields of bio-oil, water, biochar, and gas varied from 5.77 to 7.20% (by mass), 14.90 to 19.77% (by mass), 41 to 54% (by mass), and 25.33 to 32.03%, respectively, influenced by the increase in temperature. FT-IR analyses indicated the presence of characteristic chemical functions of hydrocarbons (alkanes, alkenes, and aromatics) and oxygenated compounds (phenols, cresols, ketones, esters, carboxylic acids, aldehydes, and furans), with an intensification of hydrocarbon signals at higher temperatures. GC-MS analysis identified hydrocarbons and oxygenated compounds as the main chemical classes in the bio-oil, showing a strong dependence on pyrolysis temperature. It was observed that hydrocarbon concentration in bio-oil increased from 49.7% to 57.88% (area) with increasing temperature, while the concentration of oxygenated compounds decreased from 13.88% to 6.69% (area), demonstrating that NaOH activation, combined with temperature elevation, favors the formation of hydrocarbons and the reduction of oxygenated compounds, thereby improving the quality of the produced bio-oil. Full article

Conventional epoxy polymers and their composites are increasingly challenged by environmental concerns, high manufacturing costs, and limited recyclability, necessitating the exploration of sustainable alternatives. Many research groups have sought to develop alternate polymers from various renewable resources, such as lignin, polyphenols, natural resins, saccharides, and plant oils. This new type of polymer has led to the emergence of bio-based polymers, which are often used with different reinforcements as bio-based composites. In this review, the synthesis of different bio-epoxy resins is discussed in detail along with their chemical structures. Subsequently, the enhancements in the properties of these bio-composites with the addition of different nanomaterials such as carbonaceous nanofillers (carbon nanotubes, graphene nanoplatelets, graphene oxide, etc.), cellulose-based nanomaterials, inorganic nano-silica (spherical and mesoporous), and nano-clay is explained. Lastly, the properties of these bio-composites and their applications in civil engineering are highlighted. This review has provided a detailed overview of the developments in bio-composites that can be used as a guide for the development of a new class of bio-composites using other alternate resources. Full article

In recent years, the search for sustainable, bio-based alternatives to synthetic chemicals has intensified, positioning plant essential oils (EOs) at the forefront of applied phytochemical research. The following collection of ten articles from different geographical regions, published in Plants as part of the Special Issue “Plant Essential Oil with Biological Activity: 3rd Edition,” covers various aspects of recent scientific research on plant EOs, ranging from chemotaxonomy to green biocides, with particular emphasis on chemical composition and functional properties. Further attention is given to specific predominant single constituents and their bio-selectivity, modes of action, and innovative applications in the medical and pharmaceutical sectors, particularly against major diseases such as cancer and Alzheimer’s. Full article

Palm oil and palm kernel oil are among the most widely consumed vegetable oils worldwide, but cultivar, agroecological conditions, and processing methods strongly influence their chemical properties. Although there is extensive research and production of palm oil in Southeast Asia, cultivation of its fruit in China, particularly in southern regions like Hainan and Yunnan, is severely underrepresented. This review critically summarizes current knowledge of the chemical composition, bioactive compounds, and functional properties of Chinese palm fruit components (both raw and processed), with a focus on processing-related changes and industrial applications. Current evidence suggests that Chinese palm mesocarp and kernel oils can be separated based on their general composition, fatty acid profiles, and minor lipids (such as tocopherols, carotenoids, and phytosterols), which are critical determinants of oxidative stability, nutritional quality, and processing functionality. Post-harvest practices (postmortem methods) and thermal processing strongly affect acid value, free fatty acid levels, and peroxide formation, with direct consequences for oil quality and refining efficiency. Chinese palm-derived lipids hold potential for functional foods, nutraceuticals, cosmetics, and bio-based materials used beyond their commonality as edible oil. Yet, gaps in cultivar-level chemical characterization, bioactive retention during processing, and evidence-based health evaluation remain. However, bridging these gaps using advanced analytical techniques and sustainable processing strategies will be of significant importance to endeavor towards the full utilization of Chinese palm fruit in both global food and bio-economy systems. Full article

This study evaluates the performance of recycled, long-term-aged rubber-modified asphalt (RMA) mixtures rejuvenated with soybean oil. Crumb rubber is widely used in asphalt mixtures for its ability to enhance elasticity, crack resistance, and durability. However, long-term aging leads to oxidative hardening, increased stiffness, and reduced cracking resistance, creating a need for effective rejuvenation strategies. To simulate extended field aging, plant-produced RMA mixtures were conditioned at 85 °C for five and ten days and subsequently treated with 10% soybean oil by binder weight. Mechanical performance was assessed using the Disc-Shaped Compact Tension test, Indirect Tensile Asphalt Cracking Test, Hamburg Wheel Tracking Test, and Rapid Shear Rutting Test. Rejuvenation effectively reversed aging-related deterioration, increasing fracture energy by 137–211% and improving cracking tolerance indices by 22–104%, thereby restoring or surpassing the cracking performance of unaged RMA mixtures. This improvement in flexibility was accompanied by reduced rutting resistance, with rutting tolerance indices decreasing by 52–70%, consistent with the softening effect of bio-based oils. Performance space diagrams further illustrated the trade-off between enhanced cracking resistance and increased rut susceptibility. Overall, the results demonstrate that soybean oil provides strong restorative capabilities for aged RMA mixtures, but achieving balanced field performance requires optimization of rejuvenator dosage. Full article

Co and Mo mono- and bimetallic catalysts supported on CNT-H-ZSM-5 composites were prepared and characterized using various techniques. The catalysts were evaluated for the conversion of sunflower oil (SO) into sustainable aviation fuel (SAF) hydrocarbons in the C₈–C₁₆ range. The effects of reduction temperature and metal loading were the main parameters investigated in this study. The catalyst reduced at 600 °C promoted the formation of Mo₂C species, resulting in high SO conversion (84%), complete deoxygenation, and enhanced isomerization within the C₈–C₁₆ fraction. Optimal metal loadings (2.5 wt% Co and 8 wt% Mo) and the bimetallic configuration led to superior performance compared with monometallic catalysts and physical mixtures, clearly highlighting a synergistic effect between Co and Mo species. In contrast, when waste cooking oil was used as feedstock, lower conversion and reduced selectivity toward SAF-range hydrocarbons were observed, which were attributed to the higher complexity and impurity content of this residue feedstock. Full article

Although microbial biopesticides are expanding rapidly, transforming nematophagous fungi into consistent and shelf-stable products remains a challenge. A key limitation is that fungal propagules must remain viable throughout production, storage, and delivery to ensure their efficacy in the field. This review examines formulation strategies that improve the stability, deployment, and performance of fungal biocontrol agents against gastrointestinal helminths in domestic animals and plant-parasitic nematodes. In veterinary systems, predatory fungi such as Duddingtonia flagrans primarily target infective larvae after surviving gastrointestinal transit and germination in feces. In contrast, ovicidal fungi, including Pochonia chlamydosporia, Purpureocillium lilacinum, Trichoderma spp., and Mucor spp., primarily act against helminth eggs and coccidian oocysts. This functional complementarity highlights the potential of combined fungal formulations to improve their control efficacy. We also discuss the currently available D. flagrans-based commercial products, BioWorma^® and Bioverm^®, and the practical challenges associated with dosing, administration, and farm adoption. In agriculture, we show that the Brazilian market is dominated by solid fungal nematicides designed to reduce water activity and prolong shelf life, although liquid- and oil-based systems remain relevant for specific applications. Across both sectors, the review identified formulation design, rather than fungal species alone, as a critical determinant of product performance. Emerging advances, such as microencapsulation, UV-protective matrices, improved seed-coating biopolymers, nanobiotechnology, and fungal-derived bioactive products, indicate that future progress will depend on target-oriented formulations capable of increasing stability, controlled release, and resilience under environmentally variable conditions, including those imposed by climate change. Full article

Lavandula angustifolia essential oil (LEO) was obtained by hydrodistillation of air-dried flowers collected in the Mostar region (Bosnia and Herzegovina). Its chemical composition was analyzed by gas chromatography-mass spectrometry, revealing a camphor content of 16.96%, substantially higher than the maximum value specified in the European Pharmacopoeia. Antimicrobial activity was evaluated using quantitative suspension tests according to EN 1276 and EN 1650 under simulated “dirty” conditions with organic load (bovine albumin, 3 g/L) and a 5 min contact time. High-concentration LEO (80% w/v) exhibited strong bactericidal activity against Escherichia coli ATCC 10536 and Staphylococcus aureus ATCC 6538, and yeasticidal activity against Candida albicans ATCC 10231 (>5 log₁₀ CFU/mL reduction for bacteria, >4 log₁₀ CFU/mL reduction for yeast), but was ineffective against Pseudomonas aeruginosa ATCC 15442 and Enterococcus hirae ATCC 10541. Lower concentrations (1.0% and 0.1% w/v) showed no bactericidal and yeasticidal activity, highlighting LEO’s efficacy limits. Antioxidant activity, assessed by DPPH radical scavenging, was dose- and time-dependent. Molecular docking provided insight into the interaction of major constituents with selected microbial and antioxidant-related targets. These findings highlight both the potential and limitations of LEO as a renewable bio-based resource for sustainable disinfectant formulations while emphasizing the importance of chemical composition and regulatory compliance. Full article

In this study, sustainable polyurea greases were prepared using epoxidized soybean oil (ESO) as bio-based base oil, with octadecylamine (ODA) reacted with three diisocyanates: 4,4′-diphenylmethane diisocyanate (MDI), 1,6-hexamethylene diisocyanate (HDI), and toluene diisocyanate (TDI). The diisocyanate structure dominated the thickener microstructure: MDI-ODA formed a compact short-rod fibrillar network with strong hydrogen bonding and π–π stacking, endowing the grease with the highest consistency (256), dropping point (262 °C), lowest oil separation (2.7%), and optimal thermal stability (T5% = 278 °C). HDI-ODA showed a lamellar structure with moderate performance, while TDI-ODA presented a loose porous network. Rheological tests confirmed MDI-ODA/ESO possessed the highest yield stress and structural recovery (79.5%). Tribological tests showed MDI-ODA/ESO delivered the lowest friction coefficient and wear scar diameter. Compared with non-epoxidized soybean oil (SO), ESO significantly enhanced grease performance. This improvement is attributed to the ring-opening reaction between the N–H of the ureido group and the epoxy groups of ESO, which improves thickener–oil compatibility. In addition, the polar epoxy groups promote the formation of stable lubricating films. This work verifies that diisocyanate structure and base oil epoxidation are critical for high-performance sustainable polyurea greases. Full article

The co-pyrolysis of Chlorella vulgaris (CV) and Eucalyptus branches (EP) offers a promising strategy to enhance bio-oil yield, improve resource utilization efficiency, and alleviate environmental pressures. In this study, the microwave-assisted co-pyrolysis of CV and EP at a mass ratio of 2:1 was investigated, focusing on the catalytic performance of Ni-X (X = Mg, Cu, Fe) bimetallic modified HZSM-5 zeolites. The effects of these catalysts on pyrolysis characteristics, product distribution, and bio-oil composition were systematically evaluated. Experimental results showed that the 15% Ni-Cu/HZSM-5 catalyst exhibited the best catalytic performance, achieving the highest bio-oil yield of 16.83%; it also elevated the R_m to 0.0687 wt.%/s and reduced T_s to 2084 s. Composition analysis revealed that Ni-Cu/HZSM-5 significantly promoted the formation of hydrocarbons, increasing their relative content from 11.59% (C2E1 Group) to 28.92%, while effectively suppressing the formation of nitrogen-containing compounds, reducing their content by 5.05%. Based on these results, a possible reaction pathway is proposed in which the Ni-Cu/HZSM-5 catalyst may enhance heteroatom removal through hydrodeoxygenation (HDO) at the Ni-Cu sites, followed by cracking and aromatization at the HZSM-5 acid sites. This effect may be complemented by preferential adsorption of oxygenated intermediates over nitrogen-containing species, which could help suppress the formation of nitrogenous heterocycles. This work provides theoretical guidance for the application of bimetallic zeolite catalysts in microalgae/lignocellulose co-pyrolysis, alongside a viable pathway for valorizing Eucalyptus by-products to produce high-quality bio-oil. Full article

Modern agriculture faces major challenges due to rapid population growth, climate change, and environmental constraints. Advanced polymeric systems for controlled-release fertilizers (CRFs) are essential to address these challenges. Urea is one of the most widely used nitrogen fertilizers; however, its agronomic efficiency is limited by volatilization and losses. In this study, we report a sustainable strategy to encapsulate urea using a matrix derived from industrial sulfur waste and vegetable oil, improving agronomic efficiency while valorizing industrial residues and renewable resources. Through inverse vulcanization, a sponge-like polymer (Bp-SF) was synthesized. Two urea-loaded bio-composites (Bp-SF25U and Bp-SF32U) were also prepared. FT-IR analysis confirmed urea encapsulation and the formation of polymeric structures from sunflower oil. SEM revealed a porous morphology, while contact angle measurements confirmed the hydrophobic nature of the polymer matrix. Release kinetics showed sustained nitrogen release for more than 77 days, reaching approximately 60% cumulative release, governed by diffusion, with a fraction of urea retained within the matrix, potentially enabling prolonged nutrient availability. Pot experiments with maize showed that a lower dose of encapsulated urea (79 mg) produced similar plant growth responses to a higher dose of free urea (92 mg), indicating improved nitrogen use efficiency. These sulfur cross-linked biopolymers represent a promising strategy to enhance urea efficiency while supporting greener fertilization strategies aligned with circular economy principles. Full article

The increasing demand for sustainable pest management has positioned essential oils (EOs) as viable bio-based alternatives to synthetic pesticides. This study investigates the insecticidal potential of Haplopappus foliosus EO, a Chilean endemic medicinal plant, against Drosophila melanogaster as a key toxicological model for fruit fly control. Chemical characterization identified 56 compounds, with 4-terpineol (27.27%) and α-bisabolol (10.40%) as the primary constituents, marking the first report of α-bisabolol in this species. To enhance bioavailability and overcome EO volatility, a nanoemulsion was developed, achieving an exceptionally small and stable particle size of 2.10 nm that remained consistent for over 90 days. Nanoencapsulation significantly optimized the EO’s efficacy, reducing the median lethal concentration (LC₅₀) from 120.26 µg/mL to a potent 54.57 µg/mL. While in vitro assays showed the free oil as a more potent acetylcholinesterase (AChE) inhibitor, molecular docking confirmed the high affinity of 4-terpineol and α-bisabolol for the enzyme’s active site, elucidating the neurotoxic mechanism at a molecular level. In silico analysis predicted a favorable human safety profile within GHS classes 4 and 5. Overall, this stable nanoformulation represents a sustainable biotechnological strategy for agricultural pest management, leveraging the synergistic effects and enhanced delivery of natural products. Full article

Biomass pyrolysis has emerged as a flexible platform for converting low-value residues into higher-value energy carriers (bio-oil, biochar and gas) and carbon-rich materials, with realistic potential for negative emissions when biochar is deployed in long-lived sinks. Over the last decade, three developments have driven the field forward: first, a finer mechanistic understanding of devolatilization and secondary reactions; second, major improvements in analytical techniques for characterising feedstocks and products; and third, more rigorous techno-economic and life-cycle assessments that place pyrolysis in a broader energy-system context. Recent experimental work on forestry and agro-industrial residues has clarified how biomass composition, ash chemistry and operating conditions jointly govern product yields, energy content and stability. Parallel advances in GC×GC–MS, high-resolution mass spectrometry, NMR and thermogravimetric methods have shifted the discussion from bulk “bio-oil” and “char” to families of molecules and well-defined structural domains, which can be deliberately targeted by reactor and catalyst design. Data-driven models, ranging from support vector machines applied to TGA curves to ANFIS and random forests for yield prediction, are now accurate enough to support process screening and multi-objective optimisation. At the system level, commercial fast pyrolysis biorefineries report overall useful energy efficiencies on the order of 80–86%, while slow pyrolysis configurations centred on biochar can be economically viable when carbon storage and co-products are appropriately valued. Thermodynamic analyses confirm that indirect gasification via fast-pyrolysis oil sacrifices some energy and exergy efficiency relative to direct solid-biomass gasification but may offer logistical and integration advantages. This review synthesises recent work on (i) feedstock and process characterisation; (ii) state-of-the-art analytical methods for bio-oil, biochar and gas; (iii) modelling and machine-learning tools; and (iv) energy-system deployment of pyrolysis products. Throughout, the emphasis is on how characterisation and modelling inform concrete design choices and on the trade-offs that arise when pyrolysis is considered as part of a wider decarbonisation portfolio. By integrating laboratory-scale characterisation with system-level modelling, this review aligns biomass pyrolysis with several United Nations Sustainable Development Goals (SDGs). The optimisation of thermochemical conversion pathways for forestry and agro-industrial residues directly supports SDG 7 (Affordable and Clean Energy) by enhancing the efficiency of bio-oil and syngas production. Furthermore, the deployment of biochar as a stable carbon sink for negative emissions and soil amendment addresses SDG 13 (Climate Action) and SDG 15 (Life on Land). By converting low-value waste streams into high-value energy carriers and chemicals within a circular bioeconomy framework, the research further contributes to SDG 12 (Responsible Consumption and Production) and SDG 9 (Industry, Innovation and Infrastructure). Full article

The corrosion protection of copper in acidic urban rain environments was studied using self-assembled hydrophobic layers (SAHLs) based on stearic acid (SA), with and without rosehip seed oil (RH). The limited durability of fatty acid-based self-assembled layers under acidic conditions was addressed by correlating surface wettability, morphology, and electrochemical behaviour. Contact angle and SEM analyses showed that SA alone forms a moderately hydrophobic but structurally irregular layer, whereas the addition of 2.0 wt.% RH produces a hierarchical micro/nanostructure with near-superhydrophobic characteristics (CA ≈ 149°). Electrochemical measurements in simulated acid rain solutions (pH 5, 3, and 1) revealed a strong pH dependence of protective performance. While SA-derived layers provided effective protection at pH 5, they deteriorated at lower pH due to protonation of carboxylate anchoring groups and electrolyte ingress. In contrast, SAHLs containing 2.0 wt.% RH maintained polarisation resistance in the MΩ cm² range and inhibition efficiencies above 99% at pH 3, and remained effective even at pH 1. Long-term EIS results indicate a predominantly diffusion-controlled, barrier-type inhibition mechanism associated with defects sealing and interfacial reorganisation. Notably, the rosehip seed oil used is a commercially available, bio-based material with expired shelf life, highlighting the potential of waste-derived resources for sustainable corrosion protection. Full article