Biomass Conversion and Biorefinery最新文献

Cellulose is the most abundant renewable polymer on Earth and can be obtained from various sources, such as vegetation and biomass residues. Agricultural residues represent a sustainable alternative for obtaining natural fibers. In this context, mango seeds stand out as a valuable source of starch and cellulose, with the potential to replace petroleum-derived polymers and mitigate environmental pollution. This study aimed to develop a sustainable method for extracting cellulose from mango residues and its physicochemical and structural characterization. Mango tegument flour was used and proximally characterized prior to treatment. An alkaline pretreatment was applied using 2% (w/v) NaOH 80 °C, followed by washing until neutral pH. Subsequently, the effect of H₂O₂ at concentrations ranging from 5 to 30% (v/v) and temperatures between 40 °C and 80 °C was evaluated. The extraction process was optimized through an experimental design using Design Expert 7.0 software. The optimal treatment was achieved at 62.8 °C and 5.12% H₂O₂, resulting in a 66.6% yield, with a composition of 65.08% cellulose, 19.44% hemicellulose, and 15.48% lignin. Fourier-transform infrared spectroscopy (FTIR) and X-Ray diffraction (XRD) analyses confirmed the reduction of waxes, hemicellulose, pectins, and lignin, and the presence of functional groups characteristic of the cellulosic fibers. Additionally, a crystallinity index (CI) of 77.9% was obtained. Scanning electron microscopy (SEM) revealed fibers with lengths ranging from 180–390 μm and widths between 20–60 μm, with cleaner and more homogeneous surfaces. The results indicate that the obtained cellulose fiber is suitable as a reinforcement in biocomposites, representing a biodegradable alternative with high added value for the sustainable materials industry.

The exponential growth of biodiesel production has resulted in a global surplus of glycerol, a low-value byproduct that poses significant environmental and economic challenges. Addressing this issue, we propose a novel microwave-assisted catalytic process for the efficient conversion of glycerol into acrolein, a high-value chemical integral to the synthesis of biocides, acrylic acid, and pharmaceuticals. Utilizing copper-modified zeolites (Cu-Beta, Cu-HY, Cu-ZSM-5, and Cu-Mordenite) under microwave assisted, this study achieves remarkable efficiency and selectivity. Catalysts were synthesized via wet impregnation and calcined at 500 °C, with structural integrity and uniform dispersion of Cu species confirmed through comprehensive characterization. Under optimized conditions (glycerol/catalyst ratio: 25.2, at 110 ± 2 °C), Cu-HY demonstrated superior performance, achieving 93 ± 2% glycerol conversion and 75 ± 2% acrolein selectivity. Notably, Cu-HY retained > 85 ± 2% glycerol conversion over six cycles, highlighting its exceptional recyclability and minimal deactivation. The process eliminates waste solvents and reduces energy consumption through microwave heating, aligning with circular economy principles and offering a sustainable alternative to fossil-derived acrolein production. By integrating green chemistry with industrial scalability, this work advances sustainable chemical manufacturing while positioning microwave-catalytic systems as transformative technologies for biorefinery applications. This approach underscores the potential for glycerol valorization to enhance biodiesel viability and mitigate environmental impacts.

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Spent coffee grounds (SCG) are an abundant yet underutilized lignocellulosic waste with a high potential for sustainable valorization in environmental applications. Addressing the limitations of conventional pyrolysis for carbon material production, this study aims to develop an integrated biorefinery approach to convert SCG into a sulfonated carbon adsorbent (S-char) while co-producing value-added byproducts. Unlike conventional pyrolysis, which requires high temperatures and post-synthesis activation, the proposed simultaneous carbonization-sulfonation (SCS) process enables in situ functionalization at significantly lower temperatures (100–180 °C). Through sequential delipidation, acid hydrolysis, and SCS, the process achieves three key outcomes: (1) lipid recovery, (2) fermentable sugar production, and (3) functionalized S-char with superior adsorption properties. The resulting S-char exhibited a methylene blue (MB) adsorption capacity of 103.6 mg/g, fivefold higher than conventional pyrolyzed char, owing to its engineered sulfonate groups and optimized porosity. Characterization confirms enhanced surface acidity (2.59 mmol H⁺/g) and preserved mesoporous structure, enabling efficient dye removal through combined electrostatic, (pi -pi), and hydrogen bonding interactions. This approach maintains environmental sustainability, with an E-factor (31.4) comparable to traditional pyrolysis despite its performance advantages—the cascade process addressing waste management and resource recovery challenges. By simultaneously producing high-performance adsorbents and biorefinery co-products, this work establishes a blueprint for sustainable biomass conversion with applications in wastewater treatment, biofuel production, and circular bioeconomy strategies.

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This study explores the application of sulfate-impregnated ZSM-5, ZSM-5/H₂SO₄ as a solid acid catalyst for the epoxidation of castor oil using in situ generated peracetic acid. The catalyst was optimized using the one-factor-at-a-time (OFAT) method, with the best synthesis conditions determined to be an impregnation temperature of 25 °C, sulfuric acid concentration of 0.3 M, and calcination at 550 °C. The sulfate-modified catalyst was prepared by wet impregnation of ZSM-5 with sulfuric acid, and its structure was confirmed via FTIR analysis, which showed a shift in the Si–O band from 1081 to 977 cm⁻¹, indicating successful incorporation of sulfate groups. The formation of a hierarchical porous structure enhanced reactant diffusion, leading to improved catalytic efficiency. XRD analysis confirmed that the crystalline framework of ZSM-5 remained intact after modification. Elemental analysis (EA) revealed a 3.35% increase in hydrogen content and a 0.78% reduction in carbon content compared to the initial composition, indicating the successful formation of Brønsted acid sites and effective pore activation through thermal treatment. These changes suggest that calcination not only promoted surface cleaning but also enhanced the accessibility of active sites, contributing to improved catalytic performance. Under the optimized reaction conditions of 65 °C and a 1:1:1 molar ratio of castor oil, acetic acid, and hydrogen peroxide, the catalyst achieved a 61% conversion in 30 min using 1 wt% of catalyst relative to castor oil. The catalyst retained approximately 50% of its initial activity after the first reuse cycle and further declined to around 22% by the fourth cycle. Despite the gradual drop in performance, these results are considered promising, especially given that no thermal regeneration was applied between cycles. This reuse strategy aligns with the principles of green chemistry and cleaner production by minimizing energy input, reducing waste, and simplifying the catalyst recovery process. Kinetic modeling using a hybrid approach that combines Particle Swarm Optimization (PSO) and Simulated Annealing (SA) demonstrated enhanced predictive accuracy, achieving a high coefficient of determination (R² = 0.9537). This outperformed the use of PSO alone (R² = 0.8485) and SA alone (R² = 0.8459), indicating that the hybrid strategy offers a more reliable fit to the experimental data by effectively balancing global and local optimization capabilities. This work represents the first report on the use and detailed characterization of ZSM-5/H₂SO₄ for castor oil epoxidation, highlighting its potential as an efficient and recyclable solid acid catalyst.

Agroindustrial waste poses serious threats to soil, water reservoirs, and human health due to the large amount produced daily. In this context, the review explores the valorization of citrus peel (CP) waste by converting it into biochar, highlighting recent advancements in carbon fabrication and activation while discussing their respective strengths and limitations. Moreover, it identifies reported applications of carbon derived from CP where metal and organic structures, such as CoTe, Pt, and TiO₂-Fe₂O₃, have been incorporated to enhance performance in energy storage, water remediation, and sensing. For example, in supercapacitor applications, it was observed that CP-derived carbon can deliver a specific capacitance of 460 F g⁻¹, which is comparable to other biomass-derived carbons. Furthermore, it has demonstrated excellent performance in water treatment, achieving a sorption capacity of 2342.91 mg g⁻¹ for methyl orange and a removal efficiency of 99.39% for pharmaceutical pollutants like metformin. Other noteworthy applications include its use in sensing, particularly for detecting Al³⁺ species with a detection limit of 0.695 μmol L⁻¹ as well as for sulfonated derivatives of salicylaldehyde S1, which have a detection limit of 0.87 μmol L⁻¹. The importance of this research lies in its ability to guide the selection of the optimal path for developing biocarbon according to specific requirements such as specific surface area, pore size, and electrical conductivity. By exploring the valorization of CP waste, this study also contributes to the principles of a circular economy, where waste is transformed into valuable products, reducing environmental impact. Thus, the insight gained from this investigation can assist practitioners and young researchers in visualizing the potential uses of biochar derived from CP in emerging technologies, thereby enhancing the value of agroindustrial by-products.

Producing cost-effective adsorbents derived from agricultural waste constitutes a successful undertaking technique. In this study, cellulose from Luffa acutangula peels (CLAP) served as an adsorbent for the efficient adsorption of methylene blue (MB), crystal violet (CV), and diclofenac sodium (DS). The properties of CLAP were determined through characterization using various instrumental analyses. This study indicated that CLAP’s maximum adsorption capacities were 263.15 mg/g for CV, 166.6 mg/g for MB, and 153.84 mg/g for DS at their respective optimal parameters. After testing various desorbing eluents (0.1 M), the desorption process revealed that 98.16% CV, 93.66% MB, and 88.60% DS were successfully desorbed. The cost analysis demonstrated that preparing the CLAP and adsorption study was cost-effective (286.95 INR). The results of this study have the potential to lead to progress in the science of cellulosic materials, as well as protection against aqueous contamination.

Functional foods are defined as foods which provide health benefits beyond basic nutrition. In recent times, the world has been witnessing an exponential demand for functional foods. Growing interests for healthy and sustainable life style among population, increasing awareness regarding holistic wellbeing and rising medical expenses are some possible reasons for the demand and enhanced market for the functional food industry. Of late, researches in the functional food sector focus mainly on the utilization of agricultural by-products as a potential raw material and alternative nutrient source, owing to the considerable presence of bioactive compounds and cost effectiveness. In the agricultural sector, banana production industry creates substantial quantity of biomass, including peels, leaves, fruit bunch, pseudostem, rhizome and inflorescence, among others. These by-products find several potential food and non-food applications, paving way to waste valourisation. Researchers have also identified different bioactive components from banana by-products and their associated health benefits. These powerful components can be used for the development of various functional foods by the industry. Furthermore, utilisation of banana by-products will reduce the cost of raw materials and aid in effective pollution control, thereby generating a green alternative source of bioactive compounds. This review includes a summary of existing literature pertaining to the value addition, nutraceutical properties and applications of banana by-products.

A novel lanthanum-modified biorefinery residue of wheat straw (La-BRWS) was synthesized, characterized, and applied for the removal of phosphate from aqueous solution. Characterization analyses confirmed the successful incorporation of lanthanum, which significantly enhanced the material’s adsorption performance. The results demonstrated that La-BRWS possessed a large specific surface area, a porous structure, and excellent stability across a wide initial pH range (1.01–10.83). Phosphate adsorption kinetics on La-BRWS were effectively described by both pseudo-first-order and pseudo-second-order models. The Langmuir isotherm model provided the best fit for the equilibrium data, indicating a maximum adsorption capacity of 55.74 mg P/g at 50 °C. The adsorption process was endothermic and spontaneous, reaching rapid equilibrium within 20 min, and demonstrated excellent stability in the presence of co-existing ions (Cl⁻, NO₃⁻, HCO₃⁻, and SO₄²⁻). Regeneration with 5 M NaOH retained over 99% of the adsorption capacity after five cycles. The phosphate adsorption mechanism involved ligand exchange, precipitation, and Lewis acid–base interaction. This study proposes La-BRWS as an economical and effective phosphate adsorbent derived from biorefinery residue of wheat straw, and provides new insights for reducing the cost of biorefinery.

In this study, cellulose-degrading bacteria were isolated and screened from decayed straw by Congo red staining and filter paper strip disintegration methods before the strains were identified by morphological observation and molecular biology techniques. Carboxymethyl cellulose (CMC) activity was used as a screening index to construct a composite bacterial system. The enzyme production conditions were optimized based on the results of a single-factor and response surface experiment, and the effects of pretreatment of the composite bacterial system on the anaerobic digestion (AD) performance of hulless barley straw were evaluated. Five bacterial strains with high CMC activity were screened and used for compounding, among which three bacterial strains, Bacillus velezensis, Bacillus licheniformis, and Bacillus pumilus were combined to form the optimal composite bacterial system termed CS. The optimal CS enzymatic production conditions were determined to be an initial pH of 5.2, a fermentation temperature of 40.0 °C, and a fermentation time of 70.0 h. Under these optimized conditions, the CMC activity of CS reached 114.38 U/mL. The CS degraded lignocellulose of hulless barley straw to different degrees, and degraded hemicellulose and cellulose more effectively, with degradation rates of 8.08–38.42% and 7.45–38.06%, respectively. In addition, hulless barley straw pretreatment with CS could significantly increase methane production (P < 0.05), with the highest cumulative methane production of 242.94 mL/g volatile solids (VS) obtained on the 5th day of treatment, which was 55.34% higher than that of the control and comparable to that of pretreatment with chemicals. The results show that CS pretreatment is an effective method of improving the performance of methane production by AD of hulless barley straw.

Low level of comprehensive utilization technology for crop straw has constrained the development of agricultural carbon sink. The research on the preparation and application of biochar from straw for enhancing carbon sink function is of great significance for China’s CO₂ reduction. Through the analysis of the planting area distribution and annual straw output of major crops in China from 2017 to 2022, the potential of using straw to prepare biochar in China for enhancing carbon sink function was explored. The results showed that China’s waste crop straw resources were an annual output of more than 1.0 × 10⁹ tons, which showed an increasing trend. The development of biochar in China significantly reduced CO₂ emissions and obtained a big benefit of 3.5 × 10¹¹ yuan (RMB). China’s biochar industry has broad prospects, and the industrial needs included soil improvement, fuel utilization, by-product utilization, and CO₂ emission reduction needs. This study will help increase China’s CO₂ reduction.

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