Biomass Conversion and Biorefinery最新文献

The search for sustainable alternatives for chemical products production and for industrial effluent treatment, by waste recovery and utilization, has stimulated the development of multifunctional materials with diverse applications that are also reusable. In this work, the catalytic conversion of green coconut biomass residues was conducted to produce bio-oil enriched with phenolic compounds and bio-composites for use as catalysts in conversion cycles and adsorbents of environmental contaminants. The CeO₂-HY catalyst was prepared by mechanosyntesis method and used in green coconut conversion by fast pyrolysis at 600 °C with subsequent analysis of the bio-oil by gas chromatography coupled with mass spectrometry. The starting biomass, biochar, the catalysts and bio-composites produced after pyrolysis were characterized to monitor the compositional, structural, and morphological changes that occurred before and after the process. Thermochemical studies (based on kinetic and thermodynamic parameters) and the efficiency-to-cost ratio indicated greater potential for catalysts containing CeO₂, additionally, the results indicated the catalysts applied in the process substantially modified the chemical profile of the products, depending on the type of catalyst used. The CeO₂/HY catalyst exhibited synergistic behavior, resulting in greater amount of toward phenols and esters or furans and ketones in liquid products. The produced bio-composites contains some differences in relation functional groups presents and thermal stability, which were dependent on the catalysts used. Due this they presented different skills as adsorbent and catalysts in subsequent studies. Although all most adsorbents based on bio-composites were moderated adsorbents, CeO₂ showed significantly higher results. When applied as catalysts in reuse studies, the CeO₂-HY composite catalyst showed the least variation in the quantities of the produced compound classes, in the cycles of reuse studied. The data obtained demonstrate the viability of using these catalysts and bio-composites in waste biomass valorization to produce added-value chemical products, and also wastewater treatment processes.

The rapid growth in global energy demand has increased the need for sustainable energy storage technologies. Electrochemical devices such as batteries and supercapacitors play an important role in modern energy storage systems. However, electrode materials, the main component of these devices, are often associated with high costs, limited supply, and geopolitical risks. In this context, lignin, an abundant and renewable plant-derived biopolymer, has attracted growing interest as a potential electrode material owing to its high carbon content, aromatic structure, and diverse functional groups. This review summarizes recent advances in the use of lignin as a carbon precursor and functional additive for electrochemical energy storage. It covers lignin chemistry, biomass-dependent structural diversity, isolation technologies, chemical modification strategies, and their applications in supercapacitors, lithium-ion batteries, and sodium-ion batteries. Beyond providing a descriptive overview, the review critically examines lignin-derived energy-storage materials through a continuous structure-process-property-performance framework. Particular attention is given to how biomass origin and lignin isolation chemistry determine molecular characteristics, including monomer composition, interunit linkage distribution, molecular condensation, and functional-group chemistry. These precursor characteristics are subsequently linked to carbonization and activation behavior, pore development, graphitic ordering, heteroatom retention, and surface chemistry. The resulting physicochemical properties are then correlated with ion transport, electrical conductivity, charge-storage mechanisms, electrochemical performance, and device-level relevance in supercapacitors, lithium-ion batteries, and sodium-ion batteries. By integrating these interconnected stages, this review provides mechanistic design principles for the rational development of sustainable lignin-derived electrode materials for next-generation energy storage technologies.

The sustainable production of organic acids from non-food lignocellulosic biomass is critical for advancing circular bioeconomy strategies and reducing reliance on chemically synthesized leaching agents. This study investigates acidogenic fermentation of untreated Typha latifolia, an abundant wetland biomass, to generate organic acids suitable for bioleaching. Rather than focusing on yield maximization, this work identifies key operational controls governing acidogenic performance. A full factorial design evaluated organic loading (2–6% w/v), oxygen availability (aerobic vs. anaerobic), biomass condition (fresh vs. dried), and manganese supplementation (0–50 ppm) across batch and continuous systems. Oxygen availability emerged as the dominant control variable (p < 0.05), consistently controlling solution acidification dynamics (pH drop and rate of decline), which served as a consistent operational indicator of acidogenesis. Anaerobic conditions enabled rapid pH reduction to 4.5–5.0 within 3–5 days, while fresh biomass significantly enhanced acid production due to the availability of fermentable sugars. Manganese supplementation influenced acidification rates through synergistic interactions with biomass condition but did not control final acid yield. High-performance liquid chromatography confirmed acetic acid as the primary product ( 262.75 mg/L), alongside lactic and formic acids, indicating mixed-acid fermentation pathways. Biomass-to-acid organic acid production reached approximately 50% under optimal conditions, demonstrating the feasibility of direct bioconversion. Semi-continuous operation simplified process control, with oxygen regulation sufficient to maintain stable acidogenic performance. These findings establish that process simplicity, specifically, untreated biomass and oxygen-controlled fermentation, can outweigh traditional yield-focused strategies at scale. The results provide a practical framework for integrating biomass valorization with hydrometallurgical processes, enabling the direct use of fermentation-derived organic acids as reagents in reductive bioleaching systems.

This study represents the first reported green synthesis of silver nanoparticles using Salvia hispanica microgreens as a natural reducing and stabilizing agent. Microgreens have higher nutritional content than mature plants and represent a new generation of plant-based foods. The synthesized AgNPs were characterized by FTIR, AFM, UV-Vis, FE-SEM, EDX, XRD, DLS, and zeta potential measurements to assess their antibacterial and anticancer activities. FTIR analysis confirmed the presence of bioactive functional groups (O–H, N–H, C = C, C–O, C–N, and C–H) responsible for stabilization. The AFM analysis showed that the particle size ranged from 28.98 to 69.06 nm. The AgNPs showed peak absorbance at 435 nm in the UV–vis spectrum. The FE-SEM revealed spherical to oval-shaped nanoparticles with a particle size ranging from 56.64 to 83.74 nm. The EDX spectroscopy confirms the synthesis of AgNPs, with Ag making up 72.6% of the total solution weight. The XRD shows that the particles have a face-centered cubic (FCC) structure with a mean crystallite size of 81.42 nm. Zeta potential analyses demonstrate good colloidal stability (− 32 mV). Using the agar well diffusion method, antibacterial activity was examined against Pseudomonas aeruginosa, Staphylococcus aureus, and Streptococcus mutans, revealing significant antibacterial effects, with minimum inhibition zones of 10, 16, and 14 mm for P. aeruginosa, S. aureus, and S. mutans, respectively. The AgNPs exhibited in vitro cytotoxic activity against MCF-7 breast cancer cells, with an IC₅₀ of 32.33 µg/ml. These findings suggest that the Salvia hispanica microgreens can serve as a promising source for synthesizing AgNPs, and that the synthesized Ag nanoparticles have potential antibacterial and anticancer activities that require further validation for biomedical applications.

Industrial oil products such as acidic palm oil (ACPO) are considered renewable raw materials for biodiesel production and should undergo a pretreatment process to reduce their high free fatty acid (FFA) content. Esterification is a typical process for converting FFA into fatty acid methyl esters (FAME). In this study, the pre-treatment of FFA in ACPO was investigated using sulfuric acid (H₂SO₄) supported on a solid porous material in trickle bed reactor (TBR). Catalysts were prepared by impregnating H₂SO₄ onto a hybrid support of celite and activated carbon (AC) in a 1:1 ratio. The hybrid-supported catalysts were evaluated in terms of conversion efficiency, hydrodynamic and kinetic behaviour under optimized conditions, which are 6 g of H₂SO₄ catalyst, 6 g of hybrid support, 3 mL/min of oil flow rate, 50 mL of methanol fed, 65 °C of reaction temperature and 30 min of reaction time. The highest FFA conversion of 92.36% was achieved using H₂SO₄ supported on AC, where the FFA level was reduced from 13.09% to 1.00%. In contrast, H₂SO₄ supported on Celite: AC (1:1) demonstrated a slightly lower conversion of 88.86%, reducing the FFA to 1.46%. Both systems were operated effectively for 120 min and yielded 329.40 g of treated oil. Catalyst deactivation was observed beyond these durations, likely caused by prolonged exposure to reactants and thermal conditions, which limited the active sites. Hydrodynamic parameters were also assessed. Trickle flow regime operation was confirmed, with liquid holdups of 2.46% and 1.45% for the AC and Celite: AC (1:1) supports, respectively. A second-order model best represented reaction kinetics. The rate constant, activation energy and frequency factor of H₂SO₄/Celite: AC (1:1) were 0.0201 L/mol.min, 11.011 kJ/mol and 1.276 min^− 1, respectively. These findings highlight that, while pure AC support exhibited slightly better performance, the hybrid Celite: AC support also offers a viable alternative for the treatment of FFA content in ACPO. The integration of Celite and AC provided an innovative packing system with acceptable catalytic activity. This study provides fundamental insights into the valorization of Celite for the design of packing system in TBR to produce value-added materials such as biodiesel.

Pre-treatment (PT) is a critical step in valorizing lignocellulosic biomass (LCB), enabling delignification and structural modification that facilitate conversion into value-added products. PT disrupts the recalcitrant cellulose–hemicellulose–lignin matrix while allowing recovery of valuable fractions in both solid and liquid streams. Its efficiency depends on parameters such as biomass-to-water ratio, reagent concentration, temperature, moisture content, and residence time. However, conventional analysis of PT outputs is tedious and time-intensive. In this study, an alkaline PT process was applied to rice straw (RS) in a batch reactor under varied operating conditions to determine optimal settings within a biorefinery framework. Key factors included alkali and peroxide concentrations (10–15%), temperature (45–60 °C), biomass-to-water ratio (10–13%), and residence time (3–5 h). These variables significantly affected delignification efficiency, cellulose crystallinity, and surface area. To address the complexity of predicting PT outcomes, an artificial neural network (ANN) model was developed using experimental data. The dataset was split into training (80%) and validation (20%). The ANN achieved strong predictive accuracy, with R² = 0.90 for cellulose and 0.96 for lignin. Error metrics (RMSE, MAE, MSE) showed accuracies of 86–88% for cellulose and lignin, and 75% for hemicellulose, outperforming multiple linear regression (MLR). The optimized ANN reliably predicted post-treatment compositions of lignin (3–5%), cellulose (40–50%), and hemicellulose (25–35%). This data-driven approach provides a rapid and scalable alternative for PT process optimization, reducing experimental effort while enhancing reliability in biorefinery applications.

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Anaerobic digestion (AD) of saw industry waste (SIW) provides renewable energy and nutrient-rich digestate for fertilizer. However, the efficiency of AD is often limited by prolonged hydrolysis and toxic by-product formation, resulting in large size anaerobic digester and low methane yield, respectively. Hence, the effect of thermal pretreatment on reducing lag phase, the effect of biochar on enhancing methane yield, and their combined effect on improving the overall AD performance of SIW were investigated. Thermal pretreatment (150 °C, 45 min) enhanced organic matter solubilization (2-fold increase in soluble chemical oxygen demand) and hydrolyzed cellulose, hemicellulose, and lignin by 21.27%, 26.93%, and 5.08%, respectively. The highest cumulative methane production over 35 days was achieved with biochar mediated AD of pretreated SIW (479.48 ± 6.21 ml/gVS), which represents an increase of 117.7% compared to the untreated (220.29 ± 7.14 mL/g VS). The methane yield increased to 465.75 ± 7.06 mL/g VS (111.43% increase) for thermal pretreated SIW and 365.48 ± 11.06 mL/g VS (65.91% increase) for biochar mediated SIW, compared to untreated SIW. Among the four kinetic models (transference function model, modified Gompertz model, cone model, dual pooled function model), the modified Gompertz model was best fitted for untreated SIW, transference function model for pretreated SIW and cone model for biochar mediated AD of both untreated and pretreated SIW, considering the statistical measures (R², RMSE, AIC and BIC). The phytotoxicity test demonstrated the highest germination index (201.29%) at a 20% digestate concentration derived from biochar mediated AD of pretreated SIW, highlighting its potential as an excellent soil conditioner and fertilizer. This finding aligns with the concept of the circular economy, as the conversion of organic waste into nutrient-rich digestate promotes resource efficiency, minimizes solid waste generation, and contributes to sustainable agricultural practices. Life cycle assessment study confirmed biochar mediated AD of untreated SIW as a more environmentally friendly approach than the pretreated and combined approach.

Pentatropis capensis is a medicinal plant with diverse therapeutic applications; however, its potential as a bioresource for the eco-friendly synthesis of MgO NPs remains largely unexplored. The current study focused in the green synthesis MgO NPs using P. capensis leaf extract and evaluate their physicochemical characteristics, biological activities, and developmental toxicity. Characterization of the biosynthesized MgO nanoparticles were analyzed by FE-SEM, UV–Vis, XRD, FTIR and EDX analyses. UV–Vis spectroscopy showed a characteristic absorption peak at 274 nm, while FE-SEM revealed predominantly rod-shaped and the mean particle size of the obtained nanoparticles was determined to be 27.37 nm. EDX confirmed the elemental composition of MgO NPs. The biosynthesized MgO NPs exhibited significant antibacterial activity against Escherichia coli, producing a maximum inhibition zone of 19 mm at 100 µg mL⁻¹. They also demonstrated potent antioxidant activity showing IC₅₀ values of 59.74 µg mL⁻¹ for ABTS and 54.31 µg mL⁻¹ for DPPH, along with strong anti-inflammatory activity as evidenced by showing an IC₅₀ of 21.17 µg/mL for HRBC membrane stabilization and 23.13 µg/mL for protein denaturation assay. Furthermore, the nanoparticles exhibited promising cytotoxic activity against HT-29 human colon cancer cells, with an IC₅₀ value of 53.93 µg/mL in the MTT assay. Zebrafish embryo toxicity assessment revealed minimal developmental abnormalities at concentrations below 80 µg/mL, indicating low developmental toxicity and negligible effects on growth and neurobehavior. These findings demonstrate that green-synthesized MgO NPs from P. capensis possess promising antibacterial, antioxidant, anti-inflammatory, and anticancer properties with acceptable biocompatibility, supporting their future use in biomedical and environmental applications.

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Biogenic coalbed methane is a unconventional natural gas resource. To clarify the influence of coal rank on the kinetics and molecular mechanisms of microbial methane generation, this study conducted laboratory primary microorganism degradation simulations combined with multiple analytical techniques, systematically investigating the methane production kinetics, chemical structural evolution, and key molecular parameters of coals across different ranks. Results show that low-rank coal exhibits early gas production initiation, high methane yield, and fast rates, reaching a maximum cumulative production of 263 µmol/g within 14 days. Medium-rank coal shows a delayed peak, mainly between days 21–35, reaching a maximum cumulative production of 275 µmol/g within 14 days while high-rank coal starts late, proceeds slowly, and yields significantly less methane. The total methane production has reached 191 µmol/g. Microbial activity preferentially degrades aliphatic structures in low- and medium-rank coals, enriching aromatic structures. In high-rank coal, it promotes condensation and reorganization of aromatic units, increasing stacking layers. Correlation analysis confirms that aliphatic abundance (A_al/A_ar), chain length/branching (CH₂/CH₃), and Raman D₃ band intensity are positively correlated with maximum methane production, indicating aliphatic components as key molecular determinants. This study provides new insights into the structural evolution and methane generation mechanisms during microbial degradation of coals at different metamorphic stages.

Industrial tannin extraction from maritime pine bark (Pinus pinaster) generates solid byproducts whose chemical composition and valorization potential remain insufficiently understood. This study investigates two byproducts from a two-step extraction: MPTER-1E, the undissolved solid bark fraction recovered after the first extraction/filtration step, and MPTER-FR, the final filtered agglomerated solid fraction recovered downstream from the processed liquid extract stream. This work primarily focused on MPTER-FR, while raw maritime pine bark (MPB) and MPTER-1E were analyzed as reference materials to understand better the chemical evolution induced during the extraction process. Fourier-transform infrared spectroscopy (FTIR) revealed changes in hydroxyl-, aromatic-, carbonyl-, and C–O-associated functional groups in MPTER-FR. Proximate analysis showed reduced moisture and volatiles, and increased fixed carbon in MPTER-FR on a dry-matter basis compared with the reference materials. MPTER-FR exhibited high total phenolic content (373.86 ± 0.33 mg GAE/g), condensed tannins (116.82 ± 0.97 mg CE/g), and strong antioxidant activity (up to 411.20 ± 9.41 µg AAe/mg), reflecting the high accessibility of phenolic and antioxidant-active constituents under the applied analytical conditions. MPTER-FR also exhibited a high acid-insoluble residue (78.34 ± 6.71%) and very low cellulose and hemicellulose content (< 7%), consistent with its limited contribution from an intact lignocellulosic matrix. Solvent extractive tests (Soxhlet, TAPPI T 264) revealed very high extractability (77.18 ± 3.32%), consistent with the extractive-rich nature of MPTER-FR and the presence of fatty acids and lipophilic constituents. Size-exclusion chromatography (SEC) revealed a broad molar-mass distribution in the NaOH-soluble fraction of MPTER-FR. Gas chromatography–mass spectrometry (GC-MS) further confirmed the presence of phenolic derivatives, fatty acids, fatty alcohols, and softwood resin acids. Overall, these results show that MPTER-FR is a chemically rich, extractive-based side-stream with strong potential for targeted chemical valorization, particularly through recovery of lipophilic fractions for polymer esterification or hydrophobic wood treatments within a circular bioeconomy.

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