Biomass Conversion and Biorefinery最新文献

The demand for safe and environmentally friendly food packaging is rising, leading to the growing popularity of paper-based biodegradable food packaging materials. Applying biopolymer coatings and reinforcing bioactive compounds into the packaging-grade paper matrix will enhance the physical, mechanical, and barrier properties of paper. Traditional paper coating methods, solution casting, and dip coating methods are improved with innovative spray coating methods, electrospinning, and bar coating methods. Biopolymers starch, cellulose, protein, and wax are widely used for paper coating, enhancing paper properties and showing the potential to replace current synthetic coating materials. Incorporating active materials in paper with innovative coating methods produces active paper-based packaging material that helps protect food from harmful pathogens. This review highlights the innovative strategies to improve the physical and functional properties of paper and their application in food packaging. Also, this article emphasizes paper-based smart packaging material for indicating the quality of food products.

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Synthetic fiber-based polymers constitute a significant pollution source; however, their elimination is challenging due to their extensive applications. The properties of the natural fibers can be enhanced through chemical treatment. In this study, areca fibers, subjected to ultrasonic modification with silane, were utilized in various stacking sequences, and banana fibers were used without modification. The tri-layer epoxy composites were developed following four stacking sequences using a hand layup process. The mechanical, flammability, and morphological characteristics of the developed composites were analyzed. Fourier transform infrared spectroscopy results indicate the modification of fibers after silane treatment. Morphological investigations using scanning electron microscope revealed an excellent interfacial bond between the chemically treated fibers and the matrix, leading to a 15% improvement in ultimate tensile strength, 20% in hardness, 34% in ultimate flexural strength, and 18% in impact properties. This signifies the impact of surface modification on areca fibers and stacking sequence. The results showed that fiber-matrix interaction played a crucial role in controlling the performance characteristics of the developed composites.

Mycoprotein is a nutritious food product derived from fungi that boasts a high protein content, low fat, and substantial fiber, mimicking the texture of meat. It contains essential amino acids (EAA), vitamins, and minerals. Traditionally, it is produced through the fermentation of glucose derived from starch in controlled bioreactors, where pH, temperature, and oxygen levels are optimized to enhance fungal biomass production. Advances in biotechnology have highlighted lignocellulosic biomass waste, such as agricultural residues, forestry waste, and other plant materials, as a sustainable and cost-effective alternative feedstock. This type of biomass, which includes cellulose, hemicellulose, and lignin, can be pretreated and enzymatically broken down to release fermentable sugars, promoting a circular economy by turning waste into valuable bioproducts. This review explores the feasibility of lignocellulosic biomass for producing mycoprotein through advanced pretreatment and fermentation techniques. Techniques like steam explosion and acid hydrolysis effectively break down complex lignocellulosic structures, enhancing the availability of fermentable sugars necessary for efficient mycoprotein synthesis. Furthermore, using lignocellulosic biomass facilitates waste management and supports sustainable agricultural practices. Moreover, this review discusses fungi choices suitable for mycoprotein production, such as Fusarium venenatum, Saccharomyces cerevisiae, Pleurotus sp., Neurospora sp., and Aspergillus sp.. These findings highlight the potential of mycoprotein production from lignocellulosic biomass waste to enhance food sustainability and resource efficiency.

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Clean disposal of Cr-containing tannery sludge (CTS) is a serious environmental issue because the high-content Cr is easily oxidized to toxically hexavalent. To realize the waste to energy, the CTS is used for syngas production via chemical looping co-gasification (CLCG) co-feeding with the waste surgical mask (WSM). The thermodynamic analysis is adopted to analyze the syngas’ quality, the chromium’s fate, and the N-, Cl-, and S-containing gaseous products under different gasification temperatures. Then, the effects of the mass flowrates of the steam, OC, and blending ratio of CTS in the feedstock are investigated. It is found that Cr in CTS can maintain trivalent chromium in the CLCG which is beneficial to the environment. Increasing gasification temperature can increase the Q_m from 11.44 to 13.43 MJ/kg. More steam in the gasification agent enhances the H₂ production and H₂/CO ratio in CLCG while increasing OC circulation rate leads to the gasification towards combustion.

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The aim of this work was to synthesize a high-capacity adsorbent from medlar seeds by chemical activation using phosphoric acid. The confirmation of successful biomass activation was achieved through various characterizations, including SEM–EDS, FTIR, and nitrogen adsorption–desorption. The best parameters were found to be a temperature of 500 °C, a time of 60 min, and an impregnation ratio of 2:1. The specific surface area, average pore diameter, and total pore volume were identified as 1845.32 m²/g, 2.88 nm, and 0.896 cm³/g, respectively. The performance of the selected activated carbon was evaluated by using it for the sorption of uranium (VI) in a batch system. The maximum adsorption of 52.08 mg/g was obtained under optimum conditions: pH = 3.54, adsorbent dose of 2 g/L, adsorbate concentration of 100 mg/L, particle size between 0.125 and 0.20 mm, and contact time of 90 min. Until the fifth cycle of use, the prepared activated carbon showed excellent regeneration capacity (84.23%). The pseudo-second-order kinetic and the Langmuir isotherm were the best fitted, implying the monolayer chemical adsorption process. The adsorption process could be considered as spontaneous (ΔG° < 0) and exothermic process (− 84.601 kJ/mol).

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The present study effectively employed agro-wastes in the fabrication of novel hybrid polymer composites, incorporating banana fibers (BA) and coconut shell (CS) fillers. The machining performance of the hybrid composites was assessed in relation to the effects of drilling process parameters. CNC drilling was conducted under the following conditions: coconut filler content (1%, 3%, and 5% by volume), feed rates (50, 75, and 100 mm/min), and spindle speeds (1000, 1500, and 2000 rpm). A drilling experiment was carried out using a Taguchi L₂₇ orthogonal array, and the responses, including thrust force, peel-up delamination, and push-out delamination, were analyzed in detail. The minimum thrust force was achieved with 5 vol.% coconut shell filler, a feed rate of 50 mm/min, and a spindle speed of 2000 rpm. The lowest peel-up delamination was observed with 1 vol.% coconut shell filler, a spindle speed of 1500 rpm, and a feed rate of 100 mm/min, while the minimum push-out delamination occurred under the same filler content, a spindle speed of 1500 rpm, and a feed rate of 75 mm/min. Fiber/matrix debonding, fractured fibers, and matrix cracks were identified as critical failure mechanisms through scanning electron microscopy.

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Determining cost-effective and sustainable materials is challenging. So far, the fibers from Streblus asper have not been studied for versatile applications. The current investigations focused on the extraction and characterization of novel fiber from the Streblus asper tree through the water retting process. The study revealed that the extracted fiber has a cellulose content of 55.4 ± 5.6 wt.%, hemicellulose of 12.24 ± 3.31 wt.%, and lignin of 14.25 ± 4.56 wt.%. Also, the study revealed that the fiber has a density of 1388 ± 75 kg/m³, tensile strength of 347.5 ± 16.4 MPa, thermal stability of ca. 250 °C, crystallinity index of 29.9%, and crystalline size of 1.45 nm. Additionally, the surface morphology and the elemental composition analysis indicated fibril bundles and the presence of calcium, silicon, chlorine, and potassium, along with carbon and oxygen. Furthermore, atomic force microscopy revealed high surface roughness for the extracted fiber. These findings suggest that the Streblus asper fiber is a suitable substitute for many synthetic fibers used in plastic-reinforced composites.

This study focuses on the green synthesis of zinc oxide (ZnO) and magnesium-silver-doped zinc oxide (Mg-Ag-doped ZnO) nanoparticles (NPs) via biomass conversion of Algerian Ghars date palm (Phoenix dactylifera L.) seeds. Aqueous extracts of the seeds were utilized as reducing and stabilizing agents in the biogenic synthesis process. Structural, compositional, and morphological analyses, including X-ray diffraction (XRD), Fourier-transform infrared spectroscopy (FTIR), scanning electron microscopy-energy-dispersive X-ray analysis (SEM-EDAX), and ultraviolet–visible spectroscopy (UV–Vis), confirmed the successful formation of pure and Mg-Ag-doped ZnO NPs. The UV–Vis absorption spectra showed a shift from 395.6 nm (pure ZnO) to 373.2 nm (Mg-Ag doped), with corresponding energy values increasing from 3.13 to 3.32 eV, indicating changes in electronic structure due to doping. XRD analysis revealed an increase in average crystallite size from 12.8 nm (ZnO) to 22.0 nm (Mg-Ag ZnO) and a noticeable shift in peak positions, confirming successful doping. Biological evaluations demonstrated that Mg-Ag-doped ZnO NPs exhibited enhanced photocatalytic, antibacterial, antioxidant, and antidiabetic activities compared to undoped ZnO NPs. Notably, Mg-Ag ZnO NPs showed superior antioxidant activity with an IC₅₀ of 10.78 mg mL⁻¹ and EC₅₀ of 0.79 mg mL⁻¹, compared to ZnO NPs with an IC₅₀ of 11.51 mg mL⁻¹ and EC₅₀ of 0.84 mg mL⁻¹. They also exhibited higher photocatalytic degradation efficiency of methylene blue dye (93% vs. 87% for ZnO) under UV light. Antibacterial studies showed that Mg-Ag ZnO NPs had lower minimum inhibitory concentrations (MIC) and minimum bactericidal concentrations (MBC) than pure ZnO NPs, with a MIC of 0.625 mg mL⁻¹ and MBC of 0.625 mg mL⁻¹ for E. coli, compared to 2.5 and 10 mg mL⁻¹, respectively, for pure ZnO. Furthermore, Mg-Ag-doped ZnO NPs exhibited significant α-amylase inhibition (48.0% at 0.25 mg mL⁻¹), outperforming pure ZnO NPs (38.9% at the same concentration), and showed competitive inhibition to the reference drug acarbose in antidiabetic tests. These findings highlight the potential of rationally designed biogenic ZnO nanostructures synthesized through biomass conversion of P. dactylifera seeds, especially after strategic doping, for various biomedical and environmental applications. This green synthesis approach, utilizing renewable biomass, offers an eco-friendly and sustainable route for producing ZnO-based nanomaterials with tunable properties.

Herein, spent coffee (SPC) was converted to activated carbon (SPCAC) via microwave-assisted H₃PO₄ activation. The microwave power was set at 600 W and irradiation time 15 min with an impregnation ratio of precursor/chemical activator (1-g SPC:2-mL H₃PO₄). The surface property and functionality of SPCAC was investigated by several analytical techniques that include gas adsorption (BET), SEM, XRD, FTIR, and pH_pzc. The applicability of the SPCAC adsorbent was evaluated for the removal of cationic brilliant green (BG) dye from aqueous solution. Thus, the adsorptive removal process was optimized using the Box-Benken design (BBD) to assess key adsorption parameters that include SPCAC dosage (0.05–0.15 g/100 mL) coded as (A), solution pH (4–9) coded as (B) and contact time (30 to 360 min) coded as (C). The analysis of variance (ANOVA) test shows the significant interaction between the key adsorption parameters (AB, AC, and BC). From BBD results, optimal BG dye removal (99.6%) was recorded at 0.15 g of SPCAC dose, pH 6.5, and a 30-min contact time. The adsorption mechanism of BG dye onto SPCAC was assigned to various factors that include pore filling, electrostatic forces, π-π stacking, and H-bonding. Thus, the finding of this research shows the potential benefits of converting spent coffee into active carbon by using a convenient thermochemical method with practical application for the removal of toxic cationic dyes from aqueous media.