Search Results (290)

The study comprises an in-depth characterization of compositional groups of the liquid by-products obtained from the pyrolysis of swine manure at 500 °C, with the aim of providing an alternative and efficient approach for the valorisation of this waste stream, alongside with the production of biogas and char, the latter of which can be further converted into activated carbon. Two samples were considered: de-watered cake and solid product from anaerobic digestion of swine manure. Biocrude oils were fractionated into weak acidic, strong acidic, alkaline and neutral oil fractions. Subsequently, the neutral oil fraction was separated into paraffinic–naphthenic, slightly polar and polar fractions. All fractions were analyzed by GC–MS. The major identified compositional groups were: (i) for de-watered cake: steroids (40.7%), fatty acids, FAs (23.7%) and n-alkenes/n-alkanes (23.3%); (ii) for solid product from anaerobic digestion: FAs (31.0%), phenols/methoxy phenols (26.6%), n-alkenes/n-alkanes (10.8%) and steroids (10.6%). A variety of short-chain FAs (i.e., linear saturated, mono- and di-unsaturated, cis (i-), trans (ai-), isoprenoid, phenyl alkanoic, amongst others) and methyl esters (FAMEs) were identified as well. FA distribution, nC₁₂–nC₂₀, was similar for both manures studied with nC₁₆ and nC₁₈ as major compounds. FAMEs (nC₁₄–nC₂₈, with even carbon number dominance) in the slightly polar fraction of both samples were accompanied by considerable amounts of oleic (nC_18:1) and linoleic (nC_18:2) acids, and corresponding methyl esters. Hydrocarbons, i.e., n-alkenes/n-alkanes, were in the range of nC₁₅–nC₃₄, with nC₁₈ maximizing. Anaerobically digested manure has resulted in (i) an increase in the portion of longer homologues of hydrocarbons and FAMEs and (ii) the appearance of new FAs series of long chain members nC_22:1–nC_26:1, ω-9. The comprehensive analysis of the biocrude oils obtained from the slow pyrolysis of swine manure indicates their potential for use as biodiesel additives or as feedstock to produce value-added materials. Full article

Black liquor, the side stream from Kraft pulping, is a promising feedstock for the production of renewable fuels via hydrothermal liquefaction (HTL). However, further upgrading of the black liquor HTL oil is required to reduce the oxygen content for fuel use. In this work, the hydrodeoxygenation (HDO) of black liquor HTL oil model compounds was investigated to enhance the understanding of catalyst activity and selectivity under hydrothermal conditions. The study focused on isoeugenol and 4-methylcatechol as model compounds, representing different functionalities in black liquor-derived HTL-oil. Sulfided NiMo catalysts supported on titania, zirconia, activated carbon, and α-alumina were evaluated in batch mode at subcritical and supercritical upgrading using hydrogen gas. The results show that isoeugenol was fully converted in all experiments, while 4-methylcatechol conversion varied depending on the catalyst and reaction conditions. Phenols were obtained as the main products and the maximum degree of deoxygenation achieved was around 40%. This research provides insights into the potential of hydrothermal HDO for upgrading BL-derived biocrudes, emphasising the importance of catalyst selection and reaction conditions in hydrothermal conditions. Full article

This study first adopted a liquid microbial-enzymatic co-fermentation process to enhance the nutritional value of walnut meal (WM) and sesame meal (SM), and systematically evaluated its effect on the nutrient digestibility of growing pigs. WM and SM are two underutilized high-protein by-products, whose application is hindered by anti-nutritional tannin and fiber. Optimal fermentation parameters were determined via single-factor experiments and response surface methodology, utilizing a consortium of Lactobacillus I, Candida utilis, and protease. Fermentation significantly reduced tannin (39.41% in WM) and crude fibre (28.79% in WM), reduced tannin (18.67% in SM) and crude fibre (4.00% in SM), while elevating crude protein (10.63% in WM, 7.47% in SM) and acid-soluble protein in both WM and SM. Results of the microstructure of fermented WM and SM revealed structural loosening, surface porosity, and polysaccharide degradation. Microbial community shifts highlighted the dominance of Lactobacillus and Bacillus in fermented substrates. In growing pigs, fermented WM and SM exhibited improved standardized ileal digestibility (SID) of key amino acids (threonine, tryptophan, valine; p < 0.05), alongside enhanced digestible energy (DE) and metabolizable energy (ME) for SM (p < 0.05). These findings demonstrate that liquid co-fermentation effectively degrades anti-nutritional factors, enhances nutrient bio-availability, and positions WM and SM as viable alternatives to conventional protein sources in swine diets, supporting strategies to reduce reliance on soybean meal. Full article

Microalgae have been characterized as an effective raw material for obtaining bioproducts from a biorefinery approach. However, production costs limit the large-scale production of microalgae, which makes these processes uncompetitive in the market. Therefore, in the present work, different agricultural fertilizers were evaluated as low-cost culture media for microalgae growth and the use of the biomass for biocrude production. The tests were carried out in three phases: phase I, Laboratory scale 1 L Erlenmeyer (Boeco, Hamburg, Germany) and phase II–III Pilot scale with cylindrical photobioreactors (PBRs) (Atb services S.A.S, Medellin, Colombia) with a capacity of 20 L. In phase I, four commercial fertilizers Crecilizer^® (C), Florilizer^® (F) (Fertilizer, Bogota, Colombia), AcuaLeaf Macros^® (Ma), and AcuaLeaf Micros^® (Mi) (Deacua, Medellin, Colombia) were tested separately and in combination (C + Ma, F + M, and Ma + Mi). The most effective treatments (C and F) in phase I were chosen for scale-up during phase II. In phase III, the concentration of the best treatment from phase II was increased. The biomass obtained from the best phase III treatment showed a cultivation medium cost 50% lower than the biomass obtained using Bold’s Basal Medium (BBM). Following each treatment, the harvested biomass was processed via hydrothermal liquefaction (HTL) to yield biocrude. The reduction in culture medium cost contributed to an estimated 40% decrease in the relative biocrude yield cost. Full article

Hydrothermal liquefaction (HTL) of Tetra Pak waste was investigated at 320–440 °C for 10–50 min to produce bio-crude oil. Bio-oil yield increased with temperature and time, reaching about 43 wt% at 40–50 min, while solid residue decreased and stabilized. Boiling point analysis indicated diesel- and kerosene-range fractions as dominant components. FT-IR results showed enhanced aromatic and carbonyl groups with reaction time, suggesting secondary condensation. A modified first-order kinetic model described the conversion of carbohydrates and polyethylene, with activation energies of 25.8–49.0 and 54.9–78.3 kJ mol⁻¹, respectively. The intermediate aqueous/gaseous pathway exhibited a lower activation energy (30.1 kJ mol⁻¹), highlighting its vital role in oil formation. This study advances understanding of Tetra Pak liquefaction and provides guidance for efficient composite waste valorization. Full article

The Belamcanda chinensis (L.) Redouté is a perennial herb belong to the genus Belamcanda, primarily found in China, but with additional distribution in North Korea, South Korea, Japan, and India. The rhizomes of B. chinensis have a long history of use as a traditional herbal medicine in China, one that is recognized for its effects in clearing heat, in detoxifying and eliminating phlegm, and in soothing the throat. In this review, we conducted a comprehensive search across several databases, both Chinese and international, using the primary keyword Belamcanda chinensis paired with a relevant research area (e.g., chemical composition, pharmacology). The databases included Sci-Finder, ScienceDirect, PubMed, China National Knowledge Infrastructure, Wiley, Springer Baidu Scholar and Research Gate, as well as domestic materia medica. We illustrated the chemical structures using ChemBioDraw Ultra 22.0 software. There are more than 10 proprietary Chinese medicines already on the market that consist of or originate from B. chinensis. More than 200 natural products have been isolated and identified from B. chinensis, including iridal-type triterpenoids, flavonoids, phenolics, quinones, sesquiterpenes, and polysaccharides. Modern pharmacological studies indicate that both crude extracts and monomeric compounds exhibit anti-inflammatory, anti-tumor, antioxidant, neuroprotective and anti-diabetic activities, with potential regulatory pathways. Additionally, B. chinensis demonstrates toxicity to fish, mollusks and arthropods. Clinical studies have shown that formulas containing B. chinensis as the main ingredient have a good therapeutic effect on respiratory diseases. In summary, B. chinensis presents promising prospects for application in medicine, functional food, cosmetics and agriculture. Therefore, we have reviewed the chemical composition, pharmacological activities (both in vivo and in vitro), structure–activity relationships, toxicity and clinical application of B. chinensis over the past 40 years, aiming to provide a theoretical basis for the subsequent comprehensive utilization of the plants. Full article

As a key medium in industry, lubricating oil plays a significant role in reducing friction, cooling sealing and transmitting power, which directly affects equipment life and energy efficiency. Traditional mineral-based lubricating oils rely on non-renewable petroleum, and they have high energy consumption and poor biodegradability (<30%) during the production process. They can easily cause lasting pollution after leakage and have a high carbon footprint throughout their life cycle, making it difficult to meet the “double carbon” goal. Bio-based lubricating oil uses renewable resources such as cottonseed oil and waste grease as raw materials. This material offers three significant advantages: sustainable sourcing, environmental friendliness, and adjustable performance. Its biodegradation rate is over 80%, and it reduces carbon emissions by 50–90%. Moreover, we can control its properties through processes like hydrogenation, isomerization, and transesterification to ensure it complies with ISO 6743 and other relevant standards. However, natural oils and fats have regular molecular structure, high freezing point (usually > −10 °C), and easy precipitation of wax crystals at low temperature, which restricts their industrial application. In recent years, a series of modification studies have been carried out around “pour point depression-viscosity preservation”. Catalytic isomerization can reduce the freezing point to −42 °C while maintaining a high viscosity index. Epoxidation–ring-opening modification introduces branched chains or ether bonds, taking into account low-temperature fluidity and oxidation stability. The deep dewaxing-isomerization dewaxing process improves the base oil yield, and the freezing point drops by 30 °C. The synergistic addition of polymer pour point depressant and nanomaterials can further reduce the freezing point by 10–15 °C and improve the cryogenic pumping performance. The life cycle assessment shows that using the “zero crude oil” route of waste oil and green hydrogen, the carbon emission per ton of lubricating oil is only 0.32 t, and the cost gradually approaches the level of imported synthetic esters. In the future, with the help of biorefinery integration, enzyme catalytic modification and AI molecular design, it is expected to realize high-performance, low-cost, near-zero-carbon lubrication solutions and promote the green transformation of industry. Full article

Harnessing nature’s chemistry, this study explores the enhanced biomedical potential of Terminalia ferdinandiana Exell (Kakadu Plum) by transforming its aqueous leaf and fruit extracts into bio-inspired gold nanoparticles (AuNPs). The synthesis process was optimized by varying the Au³⁺/extract ratio and pH, with nanoparticle formation verified through UV–visible spectrophotometry, TEM, and DLS analyzes. Kakadu Leaf extract–conjugated AuNPs (AuKLs), synthesized at pH 8 with a 1:25 Au³⁺/extract ratio, produced the smallest and most uniform particles (21.1 nm; PDI 0.17). In contrast, fruit extract alone failed to generate stable nanoparticles, highlighting the pivotal role of leaf phytochemicals as natural reducing and stabilizing agents. Biological evaluations revealed that both the crude leaf extract and AuKLs possessed strong antioxidant capacity, while the AuKLs further exhibited selective anticancer activity effectively inhibiting breast cancer (MCF-7) and human cervical carcinoma (HeLa) cell proliferation without harming normal mammalian breast (MCF10A) cells. A combined 2:1 leaf-to-fruit extract formulation yielded well-stabilized AuNPs (AuKPLs) with biomedical properties comparable to AuKLs, though the fruit extract alone contributed minimally to both nanoparticle formation and biological performance. Overall, this study demonstrates that the phytochemical richness of T. ferdinandiana leaves enables the green synthesis of small, stable, and bioactive gold nanoparticles. The resulting nanoconjugates, AuKLs and AuKPLs, hold considerable promise for future pharmacological and therapeutic applications, bridging traditional plant-based medicine with modern nanotechnology. Full article

Flexible polyurethane foam (PUF) is a vital material across diverse applications, and its global market is projected to continue growing. Driven by regulatory and consumer demand for sustainable materials, the PUF industry is exploring alternatives to petroleum-derived raw materials, such as vegetable oil-derived bio-polyols. Although bio-based alternatives to fossil-derived foams have been developed, their environmental benefits remain to be fully assessed. Therefore, this study evaluates the environmental performance of flexible PUF production by comparing a conventional fossil-based formulation with a bio-based alternative using a cradle-to-gate Life Cycle Assessment (LCA). The bio-based PUF reduced global warming (6%), fossil resource scarcity (9%), and mineral resource scarcity (6%), but caused significant increases in freshwater eutrophication (91%) and marine eutrophication (19%), mainly due to agricultural processes associated with soybean cultivation. Regardless of the formulation, polyol and toluene diisocyanate production were identified as major environmental hotspots. These results highlight both the decarbonization potential and the trade-offs of bio-based raw materials, underlining the complexity of achieving sustainable PUF production. Overall, the findings provide quantitative insights to guide more sustainable design and sourcing strategies for flexible PUF in the transition from fossil to renewable feedstocks. Full article

Bio-based phenolic resins were developed with phenol substitution levels of 20% and 40% with crude extracts obtained from spent coffee grounds. The experimental resins were characterized in terms of their physical, chemical and bonding properties and exhibited the typical property levels of Phenol-Formaldehyde-type resins. Plywood panels were produced bonded with the novel experimental resins, exhibiting satisfactory performance, comparable to the reference panels in terms of both shear strength and wood failure, based on the requirements of the European standards. The results demonstrate the potential of using biomass-derived compounds as substitutes for petrochemical phenol in the production of wood adhesives, thereby increasing the bio-based content of the wood panel composites produced with them and improving their sustainability. Full article

This study aimed to assess whether the fertilizing effects of compost (Com) and vermicompost (VCom) applied to a preceding wheat crop, either alone or in combination with microbial biofertilizers (MBF; arbuscular mycorrhizal fungi and nitrogen-fixing bacteria), could sustain forage maize yield across contrasting soil textures. A split–split plot trial was conducted in 2023 in sandy, loamy, and clay soils. Treatments included Com, VCom, standard mineral nitrogen fertilization, and unfertilized control, each tested with or without MBF inoculation. Maize was harvested at the milk–dough stage and assessed for biomass yield, dry matter partitioning, chemical composition, and in vitro digestibility. Interactions among factors were frequent, particularly with soil texture, but overall, Com and VCom sustained biomass yield and forage quality, especially when combined with MBF. Notably, in loamy soil, VCom coupled with MBF (38.4 t ha⁻¹) outperformed mineral fertilization (32.9 t ha⁻¹). Across soils, loam produced the highest dry matter yield (27.0 t ha⁻¹) and sand the lowest (23.7 t ha⁻¹), while clay showed variable responses depending on the amendment–MBFs combination. All plots treated with the MBFconsistently exhibited higher yields compared to their respective controls, with an average increase of 52.6% across texture and fertilization strategies. Fertilization strategy and soil texture slightly yet significantly affected maize chemical composition, while digestibility remained largely preserved. Crude protein concentration peaked under mineral fertilization in loamy soil (8.3% dry matter). These findings highlight the potential of bio-based fertilizers, especially when integrated with microbial inoculants, to reduce mineral nitrogen dependency and support the sustainable intensification of forage maize. Full article

This study analyzes, quantifies, and maps, from a bibliometric perspective, scientific research on microalgae energy production. It includes traditional simulation, machine learning, and hybrid approaches, covering 500 original articles from 2005 to 2024 in Scopus. We used Biblioshiny 4.1.2 software in RStudio 4.3.0 to categorize and evaluate the contributions of authors and journals. The studied field underwent an exponential growth in publications from 2004 to 2022, with an average annual increase of approximately 21%. Moreover, recent research focuses on photobioreactors, computational fluid dynamics, carbon dioxide capture, bio-oils, biodiesel, and hydrothermal liquefaction, increasingly integrating machine learning algorithms and hybrid methods. Since 2020, we have identified a clear trend toward combining modeling approaches to predict and improve energy efficiency, particularly for biodiesel, bio-derived hydrogen, and crude bio-oil produced via pyrolysis or hydrothermal liquefaction, which is often influenced by factors such as light, carbon dioxide, nutrients, and blending operations. Finally, recent advancements involve combining physical models with data to enable real-time optimization and control, supporting microalgae-based circular biorefining strategies. This review serves as a guide for future research in green energy materials and process modeling, inspiring colleagues to explore new ways for microalgae energy production and modeling. Full article

Lignin holds significant promise as a feedstock for biocrude production via hydrothermal liquefaction (HTL). Although lignin HTL has been widely studied, the specific depolymerization pathways associated with distinct lignin structures remain largely unexplored. This study investigates the HTL of four structurally diverse lignins: alkaline (AL), dealkaline (DAL), organosolv (OL), and lignosulfonate (LS) across 270–310 °C to elucidate structure-specific mechanisms governing biocrude yield and composition. AL and OL achieved the highest yields (16.8 ± 0.3% and 16.8 ± 2.5%), with AL-derived biocrude showing the highest carbon content (70.2 ± 0.0%) and HHV (31.0 ± 0.2 MJ/kg). In contrast, DAL and LS produced lower yields and inferior fuel quality due to higher sulfur content and lower carbon enrichment. The structures of AL and DAL, containing fewer methoxy groups, produced guaiacol-rich biocrudes (46.6% and 69.5%). Methylation in AL formed alkyl guaiacols and veratroles, while DAL favored side-chain oxidation. OL retained complex structures, forming syringols and desaspidinol, which contributed to heavier biocrude compounds. Sulfonate groups in LS were stabilized mostly as sulfides, leading to elevated sulfur content. These findings provide mechanistic insight into how lignin structure governs HTL behavior, enabling targeted control of biocrude yield and quality for renewable fuel production. Full article

Development of new sustainable pesticides represents a real challenge for researchers due to environmental issues and public health aspects. In fact, the overuse of chemical pesticides has led to environmental damage, loss of biodiversity, and pesticide-resistant pests. In a framework characterized by the necessity of new sustainable agricultural practices, this study investigates the plant Genista ulicina as a producer of bioactive compounds for potential application as eco-friendly biopesticides. First, both roots and aerial parts of G. ulicina were extracted and the main compounds in the crude extracts were identified via GC-MS. Subsequently, the crude extracts were submitted to antifungal and phytotoxic assays. In particular, the antifungal effects were evaluated on three common phytopathogenic fungi, Fusarium oxysporum, Alternaria alternata, and Botrytis cinerea, while phytotoxic activity was evaluated on two weed species: Euphorbia peplus L. and Oxalis corniculata L. Further insights were obtained on the herbicidal potential of phytochemical compounds produced by G. ulicina through in silico investigations. In particular, molecular docking analyses were performed against three key enzymes involved in essential plant metabolic pathways: acetohydroxyacid synthase (AHAS), 4-hydroxyphenylpyruvate dioxygenase (HPPD), and protoporphyrinogen oxidase (PPO). Among the compounds identified, linolelaidic acid methyl ester, 1-monolinolein, stearic acid, and palmitic acid derivatives showed promising binding affinities and favorable interaction patterns compared to reference ligands. Selected phytochemicals from G. ulicina show potential as inhibitors of key herbicide targets, suggesting their value as promising leads in the development of sustainable bio-based weed control agents. Full article

Blast furnace (BF) ironmaking remains one of the most efficient countercurrent processes; however, achieving further CO₂ emission reductions through conventional methods is increasingly challenging. Currently, BF ironmaking emits approximately 2.33 tonnes of fossil-derived CO₂ per tonne of crude steel cast. Integrating briquettes composed of biochar and in-plant fines into the BF process offers a promising short- to medium-term strategy for lowering emissions. This approach enables efficient recycling of fine residues and the substitution of fossil reductants with bio-based alternatives, thereby improving productivity while reducing energy and carbon intensity. This study investigates the reduction behavior of (i) biochar mixed with pellet fines, (ii) various in-plant residues individually, and (iii) briquettes composed of biochar and in-plant fines. The reduction rate of biochar–pellet fine mixtures was found to depend on biochar type, with pyrolyzed pine sawdust exhibiting the highest reactivity, and pyrolyzed contorta wood chips the lowest. A correlation between reduction rate and the alkali index of each char was established, although other factors such as char origin and physical properties also influenced reactivity. The effect of biochar addition (0, 5, and 10 wt.%) on the reduction of steelmaking residues was also studied. In general, biochar enhanced the reduction degree and shifted the reaction onset to lower temperatures. The produced briquettes maintained high mechanical integrity during and after reduction, regardless of biochar origin. Thermogravimetric and XRD analyses revealed that mass loss initiates with the dehydroxylation of cement phases and release of volatiles, followed by carbonate decomposition and reduction of higher oxides above 500 °C. At temperatures ≥ 850 °C, the remaining iron oxides were further reduced to metallic iron. Full article