Biomass Conversion and Biorefinery最新文献

This study explores the hydrothermal carbonization (HTC) of mango seed biomass to synthesize hydrochar, with a focus on optimization and comprehensive material characterization. The hydrochar yield was optimized using Design Expert software and Response Surface Methodology (RSM), identifying optimal conditions of 200 ℃, 3 h, and a water to biomass ratio of 1 to maximize yield and calorific value. At the optimized conditions, the hydrochar achieved a notable yield of 85.89% along with a higher heating value (HHV) of 21.4 MJ/kg, reflecting a substantial improvement in energy content compared to the raw biomass, which exhibited an HHV of only 16.35 MJ/kg. The optimized hydrochar was analyzed using Field emission scanning electron microscopy (FESEM), powder X-ray diffraction (PXRD), Fourier-transform infrared spectroscopy (FTIR), and Thermogravimetric analysis (TGA). FESEM images revealed significant pore formation due to the decomposition of cellulosic and hemicellulose components. PXRD analysis confirmed increased crystallinity and the formation of stable aromatic carbon structures. FTIR spectra showed characteristic functional groups, including aromatic C = C stretching (1500–1600 cm⁻¹), hydroxyl bending and carboxylate groups (1000–1300 cm⁻¹), and Si–O–Si or Si–O–C bonds (1015 cm⁻¹). TGA demonstrated enhanced thermal stability and reduced volatile content, making the hydrochar suitable for high-temperature applications. The higher heating value (HHV) of mango seed hydrochar (21.4 MJ/kg) significantly exceeded that of raw biomass (16.35 MJ/kg), indicating improved energy density after HTC. The results highlight that HTC enhances the porosity of hydrochar, surface area, carbon content, thermal stability, and crystallinity. The optimized hydrochar from mango seed waste, with potential applications in adsorption, energy storage, catalysis, and cementitious industries, is scalable and promising for various applications.

This research reports the fabrication and performance evaluation of a sustainable hybrid composite developed using bamboo fiber and silane functionalized biosilica nanoparticles synthesized from Manihot esculenta (cassava) tuber skins. The biosilica was obtained through a green sol-gel route and surface modified with 3-Aminoprpyltrimethoxysilane (3-APTMS) to enhance compatibility and dispersion within the epoxy matrix. Composite specimens containing a constant bamboo fiber loading (40 vol%) and varying biosilica contents (1–5 vol%) were produced via hand lay-up method. The mechanical characterization revealed that the composite with 3 vol% biosilica (RBB2) revealed the best overall performance succeeding a tensile strength of 142 MPa, flexural strength of 165 MPa, compressive strength of 150 MPa, impact strength of 6.2 J and hardness of 90 shore D. The thermal conductivity of RBB2 decreased to 0.28 W/mK, reflecting improved insulation characteristics, while thermogravimetric analysis (TGA) showed a final degradation temperature of 382 °C, confirming superior thermal stability. The synergistic action between the bamboo fiber and silane treated biosilica significantly enhanced interfacial adhesion, load transfer and barrier resistance. The research establishes that biosilica nanoparticles derived from agro-waste can serve as effective nanofillers in fiber composites, providing an environmentally friendly pathway toward high strength, thermally stable and lightweight materials.

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This study explores ultrasound-assisted extraction (UAE) as an innovative technique to enhance the yield and quality of chokeberry and blackcurrant seed oils. The effects of UAE on extraction efficiency, oxidative stability, polyphenol content, antioxidant activity, and fatty acid composition were evaluated immediately after extraction and following three months of storage. Oils obtained through conventional methods and cold pressing served as references. UAE significantly increased oil recovery, particularly in chokeberry seeds, where yields more than doubled compared to conventional extraction (1.74% in conventional process and 4.25–4.31% in UAE). Blackcurrant seed oils yields increased from 6.43% to 7.13–8.78% depending on UAE conditions applied. The extraction parameters played a crucial role in oil quality, with moderate ultrasound conditions (60% amplitude, 12 min) promoting higher polyphenol content and antioxidant activity in chokeberry oil. In contrast, more intense sonication (90% amplitude, 6 min) was more effective for blackcurrant oil. While oxidative stability decreased over 3-month storage, chokeberry oils extracted in ultrasound-assisted procedure maintained greater stability than conventionally extracted samples, retaining 92% of their original oxidation induction time compared to 78% and 86% for control and cold-pressed oils, respectively. In blackcurrant seed oils, that effect was not noted. A weak correlation between oxidative stability and total polyphenol content suggests that lipophilic antioxidants may contribute more significantly to oil preservation. The fatty acid profile remained stable throughout storage, highlighting the resistance to storage-induced changes of the extracted oils. These findings demonstrate the potential of ultrasound-assisted techniques for improving oil extraction efficiency while preserving valuable bioactive compounds, offering a sustainable alternative to conventional processing methods.

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The sustainable utilization of agro-industrial waste and byproducts has gained increasing attention for its potential to generate value-added products. Rubus glaucus Benth (Andean blackberry) is particularly interesting because of its high content of antioxidant and volatile compounds. However, postharvest losses caused by diseases and fruit quality issues result in significant economic setbacks for farmers. This study aims to increase the value of Rubus glaucus Benth byproducts by characterizing their bioactive compounds and exploring their potential applications. Pruning residues, healthy fruits, and affected fruits were collected and analyzed. Solid-Phase Microextraction (SPME) coupled with gas chromatography‒mass spectrometry (GC‒MS) was used to identify volatile compounds in the fruits, whereas antioxidant activity (DPPH and FRAP assays) and liquid chromatography‒mass spectrometry (LC‒MS) were employed to assess the phenolic composition of the pruning residues. A total of 45 volatile organic compounds were identified. The antioxidant capacity of the pruning extracts ranged from 13.854 ± 0.270 to 33.882 ± 0.628 mmol Trolox per 100 g, indicating a significant presence of phenolic acids and flavonoids. These findings highlight the potential of Rubus glaucus Benth agro-industrial residues as a sustainable source of bioactive compounds, with promising applications in food, pharmaceuticals, and cosmetics. This study demonstrates a viable pathway for waste valorization, contributing to the development of circular bioeconomic strategies and sustainable biorefinery processes.

Due to the poor biodegradability and environmental harm of mineral-based lubricants, the development and application of biolubricants are increasing. However, the unsatisfactory low temperature fluidity and poor oxidation stability of vegetable oils limit their direct use as a lubricant. This work provided a modification method of soybean oil (SBO) by epoxidation and oxirane ring opening reactions and esterification reaction. OIS-ESO-BA, OIS-ESO-IA and OIS-ESO-OA named by systematic nomenclature are products obtained by esterification of three different anhydrides (butyric anhydride, isovaleric anhydride, and octanoic anhydride) with the ring opening product, respectively. It was proved to be an effective modification method, and the aimed products can be potentially used as biolubricants. The experimental results showed that compared with SBO, the pour points of OIS-ESO-BA, OIS-ESO-IA and OIS-ESO-OA were reduced by 13, 18, and 25 °C, respectively, and it can be due to that anhydrides with different chain lengths disrupt the regularity of the molecule and promote the formation of microcrystalline structures, thus lowering the pour point. Meanwhile the oxidation stability of OIS-ESO-BA, OIS-ESO-IA and OIS-ESO-OA were increased by 22%, 37.5%, and 60%, respectively, and the improvement can be the easily oxidizable unsaturated double bond in SBO is eliminated. Tribological tests confirmed that the biolubricants exhibited good lubricating properties. These findings provide an efficient way for the evaluation of vegetable oils as biolubricants.

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Recognizing the urgent need for sustainable, high-performance energy storage solutions, the present work demonstrates a straightforward method for preparing raw chicken feather fiber charcoal (CFC) from waste chicken feathers in seal tight reactor within 2 h. Using a simple physical activation process, the CFC has been activated with NaOH at 500 °C to produce its activated carbon (CFAC). This same method has been utilized to create heteroatom (CuO)-decorated nanocomposites (CCF NCs) by combining CFC with copper acetate monohydrate (Cu (CO₂CH₃)₂·H₂O) at 500 °C. The synthesized CFC, CFAC, and CCF NCs have been then tested as electrode materials for symmetrical supercapacitors (SSCs) using 6 M KOH as the electrolyte. According to the electrochemical investigation, CCF NCs performed better than other electrode materials, with a specific capacitance of 232.7 F/g at a scan rate of 10 mV s^− 1 and 201.17 F/g at a current density of 3 A/g. Additionally, extensive cycling testing at 100 mV s-1 revealed a power density of 2549.68 W kg-1, an energy density of 80.74 W h kg-1, and an outstanding retention of 93% after 2000 cycles. It’s interesting to note that this method offers a simple and effective means to create huge amounts of activated carbon and nanocomposites, which significantly enhances the electrochemical performance of SSCs.

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Biohydrogen production by the dark fermentation (DF) process is an efficient as well as sustainable bioenergy approach. An isolate Escherichia coli SPAUBT [PQ260983] was isolated in this work, and it was used for biohydrogen production using batch fermentation mode. Initially, a 2.5 L/L of biohydrogen volume was produced in dark fermentation after single parameter optimization using the isolated bacteria. To enhance hydrogen production, optimization of the fermentation process parameters like substrate concentration, pH, and temperature was carried out using Response Surface Methodology technique (RSM) with the Central Composite Design (CCD) model. Following single- and multi-parameter runs of optimization experiments, the production of hydrogen reached 2.8 L/L. Further to inhibit the role of Volatile Fatty Acids (VFAs), biochar was employed. The use of biochar from peanut shells greatly increased hydrogen production up to a maximum production of 3.2 L/L. Biochar inhibits the accumulation of VFAs by adsorbing them onto its porous surface, thus maintaining the operational pH. Hence, this research points to the promise of coupling biochar addition with optimized fermentation strategies to drive maximum biohydrogen production.

The present study created a novel biocomposite of chitosan and acid-modified lignocellulosic biomass derived from pumpkin (Cucurbita moschata) peel for the efficient removal of methylene blue (MB) dye. The physicochemical characteristics of chitosan-based composite (hereinafter, CTN/PP-HN) were examined using techniques including pH_pzc, XRD, CHNO, FTIR, BET, and FESEM-EDX. The Box-Behnken design (BBD) numerical desirability function was employed to optimize the main adsorption factors of CTN/PP-HN dosage (0.01–0.09 g), pH (4–10), and duration (10–40). A desire function technique was used to identify the ideal circumstances for MB dye removal (85.88%), which included an adsorbent dose of 0.067 g, a solution pH of 9.5, and a contact duration of 39.7 min. The CTN/PP-HN composite exhibits a mean pore diameter of 21.57 nm, a total pore volume of 0.0304 cm³/g, and a specific surface area of 5.637 m²/g, confirming its mesoporous nature. The adsorption kinetics were defined by a pseudo-first-order, whilst equilibrium adsorption was described through the Freundlich model. For MB dye, CTN/PP-HN’s maximum adsorption capacity (q_max) was found to be 225.37 mg/g. Electrostatic forces, Yoshida H-bonding, n-π stacking, and H-bonding are some of the mechanisms that enable MB dye to be adsorbed onto the CTN/PP-HN surface. The work presents a highly efficient CTN/PP-HN composite as a potential adsorbent for effectively eliminating organic dye from water-based solutions.

This study explores the energy potential of spent tea waste (STW) for briquette production by integrating pyrolysis, Taguchi optimisation, and machine learning, a novel approach in biomass fuel research. Unlike conventional biomass briquettes, limited research has explored the optimisation of STW briquettes through thermal decomposition. Pyrolysis is introduced as a pre-treatment to enhance fuel properties, while the Taguchi method systematically optimises combustion performance. Additionally, machine learning models provide a predictive framework, identifying key factors that influence briquette quality. An L9(3³) orthogonal array was used to evaluate nine combinations of tea ash composition (100 g, 150 g, and 200 g), starch (7.5 g, 10 g, and 12.5 g), and water (80 mL, 120 mL, and 160 mL). Analysis of Variance (ANOVA) determined the effects of these variables on proximate composition and calorific value, while machine learning identified the predictive model and the most influential parameters affecting briquette performance. The results reveal that water and its interaction with tea ash significantly affect moisture content (R² = 95.2%, RMSE = 0.849), while starch and tea ash interaction govern volatile matter (R² = 62.5%, RMSE = 1.010). Fixed carbon, a key factor in combustion stability, is influenced by all briquette materials (R² = 86.7%, RMSE = 2.210). This is similar to the calorific value, which improves combustion efficiency (R² = 95.0%, RMSE = 0.313). Meanwhile, this study was unable to determine a predictive model for ash content. The optimal composition, 200 g tea ash, 7.5 starch, 80 mL water, achieves a calorific value of 24.18 MJ/kg, with 2.62 wt% moisture content, 23.05 wt% volatile matter, 61.81 wt% fixed carbon, and 10.81 wt% ash content. These results highlight the potential of STW as a sustainable biofuel feedstock. Although the calorific and moisture content meet European standards, reducing ash content remains a key challenge due to the material’s high mineral content and trade-offs in the pyrolysis process. This study demonstrates the feasibility of combining thermal pre-treatment, statistical optimisation, and machine learning to improve biomass briquette performance and support circular economy initiatives.

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In this study aims to determine the changes in growth, astaxanthin, protein, lipid, caretenoid and chlorophylla, b content by cultivating Scenedesmus acutus and Chlorella vulgaris species for 12 days in 9 different culture media (BG11, Jaworski’s, Cheese Whey, Different Molasses Concentrations, Mineral water, Tap Water, and Nitrogen-Free Jaworski’s Medium). The analyses revealed that in all concentrations of industrial waste molasses, both species exhibited much higher growth and protein content compared to other culture media. It was determined that the astaxanthin content in Chlorella vulgaris reached a maximum value of 2.718 µg ml^− 1 in cultures prepared with 4 g L^− 1 concentration of molasses culture medium, while in Scenedesmus acutus, this value increased to 2,945 µg ml^− 1. The lipid content reached its maximum value on the sixth day in cultures of Scenedesmus acutus(83,15%) and Chlorella vulgaris(83,05%) prepared with molassses concentration of 4 g L^− 1. Carotenoid, chlorophyll a and chlorophyll b levels were found to be significantly lower in culture media prepared with whey compared to other media. Determining the optimal culture media contributes to increased efficiency in algae biomass production, enabling more sustainable and economical production of high-value bioactive compounds such as astaxanthin.