Removal Of Hemicellulose Research Articles

High-Strength, Thermally Stable, and Processable Wood Fiber/Polyamide Composites for Engineering Structural Components.

Hybrid wood fiber/plastic composites offer a high-value-added utilization for agroforestry waste, which also providing a promising solution for reducing white pollution. However, the interface incompatibility between natural wood fibers and polymers significantly impairs the mechanical properties of the composites. Herein, a straightforward procedure is proposed to solve this problem, involving the removal of low-thermal-stability hemicellulose from wood fibers by hydrothermal pretreatment, followed by compositing with polyamide to produce hydrothermally treated wood fiber/polyamide composites (HWPACs). No chemical additives are required to improve the interface compatibility of composites, which simplifies the manufacturing process and provides environmental benefits. The effective removal of hemicellulose (78.35%) significantly increases the onset thermal degradation temperature of hydrothermally treated wood fibers (HWFs) by 27.49°C. This prevents the generation of micro gaps during thermal processing, thereby improving the interfacial bonding strength between HWFs and polyamide. HWPACs exhibit higher mechanical strength (flexural strength 139.45MPa) and thermal stability while maintaining a low density (1.22gcm-3). Various lightweight, high-strength, and multi-shape materials can be prepared by hot pressing, injecting, and printing HWPACs, suggesting their suitability for applications in engineering structural components.

An investigation into the microstructural evolution and shrinkage control in internally cured mortars with milkweed fibres

This study presented a significant advancement in the use of Milkweed (MW) fibres as internal curing agents in low water-to-cement (w/c) cementitious materials. The research focused on how different pre-treated MW fibres, with different composition, can impact internal curing efficacy in reducing autogenous shrinkage of cement mortars. In addition, the hydration behaviour and microstructural development were revealed using a series of tests including setting time, compressive strength, flexural strength, scanning electron microscopy (SEM), and thermogravimetric analysis (TGA/DTG). A key finding of this study is the remarkable reduction in autogenous shrinkage, with using 0.1 % wt. pre-treated MW fibres leading to up to 28 % reduction at 7 days, compared to plain mortars. Furthermore, internal curing effect resulted in narrowing the compressive strength gap between the reference mixes and those with pre-treated MW fibres in the later stages of hydration. It was also found that the removal of hemicellulose through hybrid treatment can reduce the delay in the final setting time of cement from 45 minutes to 18 minutes. Additionally, while the incorporation of N- and HT-treated MW fibres had negligible effects on drying shrinkage, the inclusion of HY-treated MW fibres led to a 15 % increase in drying shrinkage at 7 days. This difference in behaviour was attributed to the presence of lignin in N- and HT-treated fibres. Lignin was found to play a crucial role in influencing the drying shrinkage, microstructural development, and mechanical properties of MW fibre-incorporated cementitious mixes. Acting as a protective barrier, lignin shielded the MW fibres from cement infiltration into their lumina. Moreover, it served as both a physical and chemical barrier, reducing moisture transport through the capillary network during drying. In conclusion, this study demonstrated the potential of using pre-treated MW fibres as internal curing agents to effectively reduce autogenous shrinkage, with minimal compromise in terms of the compressive strength of cementitious composites.

Machine learning prediction of mechanical properties of bamboo by hemicelluloses removal

The use of bamboo as a sustainable material is becoming increasingly prevalent; however, the optimisation of its mechanical properties remains a significant challenge. In this study, different concentrations of sodium hydroxide (NaOH) were used to remove the hemicellulose of bamboo and the effect of mechanical properties such as modulus of elasticity, flexural strength and elastic limit were evaluated. A total of 90 samples of data were collected and five machine learning algorithms including Principal Component Regression (PCR), Partial Least Squares Regression (PLSR), Ridge Regression (RR), Lasso Regression (LR) and Elastic Network Regression (ENR) were employed to build predictive models based on these properties. The models were trained and tested using 5-fold cross validation. The results showed that the mechanical properties of elastic modulus and elastic limit of bamboo medium were enhanced to 9.63 GPa and 66.44 MPa treated by 10 % NaOH, while the flexural strength of bamboo medium was up to 147.29 GPa with 5 % NaOH. The Ridge Regression algorithm was the best compared to other four algorithms. This methodological approach is not only offers an efficient way to optimize the mechanical properties of bamboo, but also enhances sustainable practices in the environmental sector.

Optimizing corncob pretreatment with eco-friendly deep eutectic solvents to enhance lignin extraction and cellulose-to-glucose conversion

Deep eutectic solvents (DES) are an eco-friendly, cost-effective alternative to traditional ionic liquids for biomass pretreatment, with unique characteristics encompassed by hydrogen bond donor (HBD), the molar ratio of hydrogen bond acceptor (HBA) to HBD, temperature, and time affecting efficiency. Despite its potential, a comprehensive study exploring the interplay of these factors is limited. This study explores the optimization of pretreatment variables using choline chloride/lactic acid (1:5) via the response surface method (RSM). It aims to evaluate the effects of time and temperature on lignin extraction, cellulose-to-glucose conversion, and hemicellulose removal. Employing a 22 central composite design with temperature (80–140 °C) and time (2–6 h) as variables, optimal conditions were 123 °C for 6 h. Results include 90.08±1.42 % lignin extraction, 68.77±6.9 % cellulose-to-glucose conversion, and 77.34±0.85 % hemicellulose removal, with 52.52±8.07 % lignin recovery. The fractions of pretreated CC and lignin recovered in the optimal condition found were characterized by X-ray diffraction (XDR), Fourier transform infrared spectroscopy (FTIR), 1H, 13C, 2D-HSQC NMR spectroscopy, Thermogravimetric analysis (TGA/DTG), Gel Permeation Chromatography (GPC) to elucidate chemical characteristics of the materials obtained and facilitate downstream valorization. High efficiency was achieved in lignin extraction and cellulose conversion, and addressing solvent viscosity and DES recycling will further enhance the potential for industrial scalability.

Microwave-Assisted Acid and Alkali Pretreatment of Napier Grass for Enhanced Biohydrogen Production and Integrated Biorefinery Potential

Napier grass, a promising lignocellulosic energy crop, presents a complex composition that limits its bioconversion into fermentable products. To address this challenge, we applied microwave (MW) pretreatment assisted by acid and alkali, using varying chemical concentrations (0.5–1% w/v) and pretreatment times (3–10 min). Acid-catalyzed MW pretreatment achieved a maximal hemicellulose removal of 69.8%, while alkali-catalyzed MW pretreatment resulted in significant lignin removal of 65.5%. Without chemical catalysis, the pretreated hydrolysate significantly increased hydrogen yield to 38.0 ± 2.9 mL H2/g volatile solid (VS), five times greater than that obtained from untreated biomass. Hydrogen yield was further enhanced when the MW-pretreated solid underwent simultaneous saccharification and fermentation. The highest hydrogen yield of 89.2 ± 7.2 mL H2/g VS was achieved from alkali-catalyzed MW pretreated solid (0.5% w/v NaOH, 5 min), with a chemical oxygen demand (COD) solubilization of 62.6%. Increasing the NaOH concentration to 1% (w/v) slightly decreased hydrogen yield but significantly increased COD solubilization to 85.8%. The high carbohydrate content facilitated rapid cellulase hydrolysis, producing and accumulating a high concentration of fermentable sugars. However, this accumulation subsequently led to a shift towards lactic acid formation. The improved hydrogen yield and increased COD solubilization, along with the shift towards lactic acid production, suggest the possibility of optimizing this process for simultaneous production of multiple valuable products in an integrated biorefinery approach, potentially enhancing the economic viability of biomass conversion.

Significantly enhancing enzymatic saccharification of poplar waste through the effective removal of lignin and hemicellulose by 1-butanol-Na3PO4-water treatment

Na3PO4-H2O-assisted 1-butanol pretreatment was established for changing the structure of poplar waste and improving its enzymatic efficiency. After poplar waste was pretreated at 180 °C for 60 min, 51.3 % of xylan and 52.5 % of lignin were eliminated. After the enzymatic saccharification of treated poplar waste, the yield of reducing sugars reached 75.3 %. A series of characterizations demonstrated that Na3PO4-H2O-assisted 1-butanol pretreatment altered the poplar composition with improved cellulose accessibility from 231.2 to 459.5 mg/g and reduced surface area of lignin from 384.2 to 255.3 m2/g. Molecular simulations, quantum chemical calculations and independent gradient model analysis were performed on the poplar model, and the 1-butanol-Na3PO4-H2O pretreatment resulted in the increase of electrostatic and van der Waals repulsion forces in lignin and xylan, explaining the efficient lignin and xylan removal. A comprehensive interpretation of mass balance and energy flow was applied to assess the entire pretreatment process. This eco-friendly 1-butanol-Na3PO4-H2O pretreatment effectively broken the encapsulation of cellulose by enzyme inhibitors and improve biomass pretreatment effect.

Effect of eucalyptus globulus pulp properties on fock reactivity

AbstractDissolving-grade pulps serve as the primary material for producing regenerated cellulose fibers, and their utilization is steadily increasing. Despite extensive research efforts, it remains necessary to deepen our understanding of the inherent factors that impact pulp reactivity apart from the well-known degree of polymerization. The Fock reactivity test is commonly used to quantify the reactivity of cellulose pulp by measuring the percentage of cellulose that reacts with carbon disulfide. Dissolving pulps typically require a reactivity of over 90%. Hemicellulose content, intrinsic viscosity, cell wall porosity, crystallinity, and accessible area of four different pulps were characterized and distinct treatments were employed to try to separate the effect of different pulp properties and assess their effect on Fock reactivity. Hemicelluloses removal by xylanase and cold caustic treatments (86% removal) increased the Fock reactivity by 30%, from 55.7% to 71.3%. Assuming the hemicelluloses are fully accessible by the CS2, cellulose reactivity increased from 35.6% to 69.5%,but at the expense of an intrinsic viscosity decrease from 990 cm3/g to 689 cm3/g. This unexpected intrinsic viscosity decrease can be due to the cellulose de-shielding effect provoked by hemicellulose removal and some cellulose degradation during cold caustic extraction. Vibrational impact ball-milling applied on a pulp with 5% hemicellulose content notably boosted Fock reactivity by 56%, from 54% to 84.5%, but two pulp properties, intrinsic viscosity, and crystallinity, decreased concurrently due to the high-energy treatment. This phenomenon complicates identifying a direct correlation between heightened reactivity and a single parameter. To address this, endoglucanase treatment was used to separate intrinsic viscosity from crystallinity, clarifying their contributions to changes in Fock reactivity. Unfortunately, the effect of a given physical or bio/chemical pulp treatment affects more than one pulp property, always including the cellulose degree of polymerization, which has made it difficult to isolate the pulp properties that affect Fock reactivity. Several processes have been tested to obtain pulp with dissolving potential.

Examination of the Effects of Chemical Treatments on the Mechanical, Chemical, and Physical Characteristics of <i>Hibiscus rosa-sinensis</i> Plant Fiber

Natural fibres in recent years have been found to contribute a great share in making composites. Hibiscus rosa-sinensis plant fibres which are natural were used in this work and have not yet been tried to make the composites so far and easily available thus making this study very necessary it aims to perform various chemical treatments and to study the physical and chemical properties of them. The methodology adopted was that literature review, problem identification, extraction of fibres, treatment of fibres, chemical and mechanical testing of fibres, results and discussions and conclusion. Fibre chemical composition tests were also done to determine the constituents of the fibres. Two chemical treatment methods (alkalinization and benzoylation) were proposed in this work. Chemical treatments were found to improve surface roughness. Using Scanning Electron Microscopy (SEM), researchers examined the fibres' structural and morphological alterations and discovered that components like pectin were largely eliminated. The structural properties of fibres were known from X-ray diffractograms, and crystallinity percentages were found for the cellulosic fibres. Fourier Transform Infrared (FTIR) spectroscopy presented the spectra of the fibres which revealed the structure of organic compounds and the presence or the absence of functional groups. It showed the partial removal of hemicellulose and lignin. Axial tensile tests were performed for the fibres to know the maximum tensile force and percentage elongation. Chemical treatments partially removed impurities in the fibres and made morphological changes. The improvements in mean tensile values and percentage elongation were found in 5% alkali-treated and benzoylation-treated fibres, 56% and 63% higher than the untreated fibres respectively.

Hydrothermal alkaline treatment of lignocellulosic biomass for microcrystalline cellulose generation at subcritical water

Like lignocellulosic biomass, wood waste sawdust is rich in cellulose and can potentially be used as a source of microcrystalline cellulose (MCC) production via removal of hemicellulose and lignin constituents. Under hydrothermal alkaline treatment (100 to 140 °C), the breaking in the linkages of lignin and hemicellulose groups may happen, resulting in the solid residue, which is known as a cellulose-rich solid product. Results of FTIR analysis indicated that the removal of non-cellulosic constituents improved with increasing operating temperature and/or the prolonged treatment time. The XRD diffractogram pattern proved that improving the operating parameters (temperature and/or time) may also improve the crystallinity index of the solid product. On the contrary, the yield of the solid product decreases with increasing operating temperature and/or the prolonged treatment time.

Acid-assisted pretreatment for sweet elephant grass in choline chloride/glycerol DES: Experimental and mechanism study

Sweet elephant grass (SEG), a promising bioenergy grass, possesses considerable potential for bioenergy production. However, research on its pretreatment and utilization remains limited. In this study, small quantities of Brønsted acids were introduced to a deep eutectic solvent (DES) comprising choline chloride (ChCl) and glycerol (Gly) for SEG pretreatment. Under mild conditions (110 °C, 2 h), a maximum lignin removal rate of 90.08 % and a complete hemicellulose removal could be accomplished in the presence of Brønsted acid. Cellulose retention rates consistently above 70 % were obtained in all the cases, and a desirable glucose yield up to 94.07 % was achieved from the resulting cellulose after further enzymatic hydrolysis. The pretreatment mechanism was elucidated through a combination of characterizations and theoretical calculations, which demonstrated effective disruption of lignin and lignin-carbohydrate complex occurred by the CH···π, HO···H, and Cl···H bond interactions between lignin and DES. Furthermore, the scission of β-O-4 bond was promoted by Brønsted acids in DES. This systematic investigation paves the way for unraveling the mechanism of the efficient pretreatment of lignocellulose in acidic DES.

Use of Low‐Energy Ultrasonication to Enhance the Purity and Morphology of Cellulose Nanofibers Prepared from Areca Nut Shells

AbstractThe isolation of cellulose nanofibers from areca nut shell has been successfully carried out using a simple alkaline treatment, acid hydrolysis, and followed by a morphological modification using low‐energy sonication method. The alkaline treatment consists of dewaxing and bleaching process to remove lignin, while acid hydrolysis process was carried out to remove hemicellulose. Mechanical fibrillation was carried out via ultrasonication and low‐power homogenization with 100 W cleaner and 3 W homogenizer to obtain fine fibers. Following the scanning electron microscope (SEM) result, the ultrasonicated treatment sample showed better lignin and hemicellulose removal processes and increased dispersity, as well as reduce diameter of cellulose fibers from 710.4 to 451.6 nm. The particle size analyzer (PSA) showed that the colloidal cellulose after sonication provide a frequent diameter of 56 nm. Fourier transform infrared (FTIR) spectroscopy result showed that sonication is an effective removal process of noncellulosic components. X‐ray diffraction (XRD) analysis showed that the crystallinity of nanocellulose decrease following the sonication process. Hence, low‐energy ultrasonication is a viable approach to enhance the morphology and mechanical strength of cellulose nanofiber.

Properties of poly(butylene adipate-co-terephthalate)/thermoplastic starch filled with treated and untreated sugarcane bagasse fiber

Sugarcane bagasse, comprising fibrous rind and spongy pith, is frequently employed as a reinforcing agent in both concrete and plastic composites. In thin plastic films, sugarcane bagasse is typically utilized as finely ground particles within the composite film. The integration of this agricultural byproduct into biodegradable plastic films could potentially lower production expenses and promote the film's biodegradability. This study presents the development of poly(butylene adipate-co-terephthalate) (PBAT)/thermoplastic starch (TPS) (90/10) formulations incorporating varying loadings of sugarcane bagasse fibers. The impact of alkaline and silane surface treatments on tensile strength, thermal properties, and water barrier properties was investigated. Upon the inclusion of sugarcane bagasse (5%, 10%, 15%, and 20%), a decrease in tensile strength from 23.47 to 8.41 MPa and elongation at break from 1135% to 55.83% was observed. Conversely, the Young's modulus increased from 47.12 to 188.50 MPa following the addition of 20% sugarcane bagasse in the PBAT/TPS matrix. Modest enhancements in tensile properties, thermal characteristics, and water barrier properties were noted after treating the bagasse fibers with alkaline and silane. Scanning Electron Microscope (SEM) analysis revealed that silane-treated sugarcane bagasse exhibited increased surface roughness due to the removal of lignin and hemicellulose, facilitating better adhesion between the fibers and the PBAT/TPS matrix.

A soft processing technology for the extraction of cellulose from plant residues and agri-food wastes

In this study, cellulose was extracted from giant cane (GC), Posidonia oceanica seagrass (PO), coffee silverskin (CS), and brewer's spent grain (BSG) as alternatives to conventional sources of cellulose. The extraction protocol involved three steps: i) hemicellulose and lignin removal through alkaline hydrolysis in a 5% (w/v) NaOH solution (solid-to-liquid ratio = 1:100 g/mL, T = 25 °C, t = 2 h, ω = 300 rpm), ii) removal of organic compounds and ashes through a 95% (v/v) ethanol solution (solid-to-liquid ratio = 1:25 g/mL, T = 25 °C, t = 0.5 h, ω = 500 rpm), and iii) double bleaching in a 1% (w/v) acidic (pH = 4) NaClO2 solution (solid-to-liquid ratio = 1:50 g/mL, T = 90 °C, t = 1.5 h, ω = 500 rpm). Yield, purity, crystallinity degree, and morphology of cellulose extracted through a soft-chemical cascade process were assessed by gravimetric, infrared (FT-IR), nuclear magnetic resonance (NMR) spectroscopy, X-ray diffraction (XRD), and scanning electron microscopy (SEM) analyses. Averaged cellulose extraction yields of 36.4, 38.6, 23.1, and 22.2% for GC, PO, CS, and BSG were obtained, respectively. All cellulose samples had high purity, though lower than the ultra-pure bacterial cellulose, which was due to the slight contamination from unremoved hemicellulose and lignin residues. Cellulose samples exhibited similar chemical features and the typical fibril-like morphology of microcrystalline cellulose (6–13 μm in width). The versatility of the proposed extraction procedure supports the sustainable conversion of low-cost organic biomasses to valuable products with manifold industrial applications (e.g., food packaging).

Establishment of efficient system for bagasse bargaining: Combining fractionation of saccharides, recycling of high-viscosity solvent and dismantling

Sugarcane bagasse (SCB) has a recalcitrant structure, which hinders its component dismantling and subsequent high value utilization. Some organic solvents are favorable to dismantle lignocellulose, but their high viscosity prevents separation of components and reuse of solvents. Herein, ethylene glycol phenyl ether (EGPE)-acid system is used as an example to develop green and efficient methods to dismantle SCB, purify polysaccharides and lignin, and reuse solvents. Results show that dismantling SCB at 130 °C, 0.5 % H2SO4, and 100 min can obtain 85.5 % cellulose recovery, 94.1 % hemicellulose removal and 83.7 % lignin removal. Different molecular weight saccharides are separated by membranes filtration and centrifugation, and lignin recovered by antisolvent precipitation. The solvent recovered by distillation, achieving high dismantling efficiency of 89.2 % cellulose recovery, 94.1 % hemicellulose removal and 94.4 % lignin removal after four recycles. Results show a promising approach for the closed-loop process of dismantling lignocellulose, fractionating saccharides, and reusing solvents in high-viscosity systems.

Optimization and characterization of a biphasic solvent system for vinegar residue pretreatment: Enhanced fractionation efficiency, propionic acid production, and sustainability

This study introduces a novel biphasic solvent system composed of phenoxyethanol and p-Toluenesulfonic acid (p-TsOH) for the pretreatment of vinegar residue (VR). The system achieves high cellulose retention (80.15 %) and effective removal of hemicellulose (97.10 %) and lignin (88.31 %) under mild conditions (127°C, 1.9 h). Structural changes in pretreated VR were analyzed, revealing significant improvements in enzymatic hydrolysis yield, achieving nearly 90 % conversion.The hydrolysate supports fermentation by Acidpropionibacterium jensenii, leading to efficient propionic acid production. The sugar-to-acid conversion rate of 28.15 % highlights the hydrolysate’s quality for lignocellulosic biotransformation. Density functional theory and molecular dynamics simulations confirm stable lignin interactions in the system, driven by hydrogen bonding, van der Waals forces, and π-π stacking, which promote lignin removal. Recycling phenoxyethanol over four cycles maintains high cellulose digestibility (84–95 %) and consistent delignification rates (88–89 %). The mass balance validated the efficient fractionation of biomass. A comprehensive analysis was conducted on the sustainability, safety, and environmental impact of the system. In conclusion, this study presents a novel biphasic solvent system that effectively fractions biomass, enhances solvent recovery, and reduces environmental impact. This system demonstrates broad applicability to different lignocellulosic biomasses, contributing to both economic and ecological sustainability.

Enhancing enzymatic conversion of castor stalk through dual-functional ethanolamine pretreatment

Castor stalk from hemp plants is an attractive lignocellulosic feedstock for biomass refining valorization due to its similar chemical composition to hardwoods. In this study, the castor stalk fibers were pretreated with efficient dual-functional ethanolamine to achieve delignification and swelling of the cellulosic fibers, followed by cellulase enzymatic digestion for biomass conversion. Experimental results showed that ethanolamine pretreatment at 160 °C for 1 h effectively removed 69.20 % of lignin and 43.18 % of hemicellulose. In addition to efficient delignification and removal of hemicellulose, the study also revealed that supramolecular structure of cellulose was another major factor affecting enzymatic hydrolysis performance. The lowered crystallinity (60–70 %) and swelled crystal sizes (2.95–3.04 nm) promoted enzymatic hydrolysis efficiency during the heterogeneous reaction process. Under optimal conditions (160 °C, 1 h; enzyme loading: 15 FPU/g substrate), promoted yields of 100 % glucose and over 90 % xylose were achieved, which were significantly higher than those obtained from untreated castor stalk. These findings highlighted the effectiveness of the dual-functional ethanolamine pretreatment strategy for efficient bioconversion of lignocellulosic feedstocks. Overall, this study provides valuable insights into the development of new strategies for the efficient utilization of biomass resources, which is essential for the sustainable development of our society.

Oil palm frond leaves (OPFLs), a high recalcitrant biomass as an alternative cellulose source for glucose conversion

Among the oil palm biomass, oil palm frond leaves (OPFLs) are under-valued since they can be classified as a high recalcitrance feedstock due to the high lignin and hemicellulose content. This work proposes a new way of using OPFLs as alternative cellulose sources for glucose conversion by an application of various pre-treatments at varying parameters. From green pre-treatment, steam explosion (SE) is much more effective in disrupting the OPFLs structure in contrast to hydrothermal (HT) pre-treatment, by a vast dissolution of hemicellulose and depolymerization of lignin. The pre-impregnation with H2SO4 prior to steam explosion was beneficial to enhance the hemicellulose removal up to 89.94 %. The 2D-HSQC NMR analysis divulged the reduction of ß-O-4 linkage and S/G value after the SE and HT pre-treatment, verifying the degradation of lignin-carbohydrate linkage in OPFLs. Meanwhile, the dilute NaOH pre-treatment enhanced the delignification by 87.14 %. SEM analysis revealed a well-disrupted structure of pre-treated OPFLs exposing a higher cellulosic fraction, whereas SEC analysis divulged a decreasing pattern of degree of polymerization of cellulose. The enzymatic analysis revealed that pre-treated OPFLs yielded higher glucose ranging from 29.81 % to 49.98 % w/w, which was ∼3-fold higher than raw OPFLs (14.31 % w/w). A maximum cellulose digestibility (100 %) was achieved by steam-exploded OPFLs after 72 h of enzymatic hydrolysis. This suggests the potency of various pre-treatments to enhance enzymatic saccharification of OPFLs producing a higher glucose yield.

Optimization of Cellulose Recovery Using Deep Eutectic Solvent Fractionation: A Response Surface Method Approach

Lignocellulosic biomass is a crucial renewable energy source for producing biofuels and valuable compounds, making it an attractive alternative to fossil resources. In this study, an environmentally friendly method was developed for cellulose fractionation from sugarcane bagasse using deep eutectic solvents (DESs), focusing on achieving high cellulose purity and specific physicochemical properties. The effects of different parameters were investigated by comparing four DESs: choline chloride–lactic acid (ChCl-LA), choline chloride–glycerol (ChCl-G), choline chloride–urea (ChCl-U), and choline chloride–polyalcohol (ChCl-P), under various reaction temperatures and times. The fractionation process was conducted under standard conditions at a temperature of 100 °C for 120 min with a 1:1 molar ratio. The results indicated that all DESs produced comparable cellulose recovery, ranging from 91.83% to 97.07%. A relatively high cellulose recovery was observed in the presence of ChCl-LA, at 95.47%. In addition, ChCl-LA demonstrated the highest efficiency in removing hemicellulose and lignin, at 95.36% and 93.38%, respectively, and high recovery yields of 70.45% for hemicellulose, and 70.66% for the lignin fraction. The fractionation conditions were further optimized using response surface methodology (RSM), achieving a ChCl-LA ratio of 1:2 v/v at 120 °C for 120 min. This resulted in impressive yields: 97.86% cellulose recovery, 96.50% hemicellulose removal, 74.40% hemicellulose recovery, 77.3% lignin recovery, and 71.5% lignin yield from sugarcane bagasse. These results closely match the predicted values, emphasizing the effectiveness of the process and its potential for economic application in lignocellulosic biorefinery operations.

From Field to Pharmacy: Isolation, Characterization and Tableting Behaviour of Microcrystalline Cellulose from Wheat and Corn Harvest Residues.

A lack of strategies for the utilization of harvest residues (HRs) has led to serious environmental problems due to an accumulation of these residues or their burning in the field. In this study, wheat and corn HRs were used as feedstock for the production of microcrystalline cellulose (MCC) by treatment with 2-8% sodium hydroxide, 10% hydrogen peroxide and further hydrolysis with 1-2 M hydrochloric acid. The changes in the FT-IR spectra and PXRD diffractograms after chemical treatment confirmed the removal of most of the lignin, hemicellulose and amorphous fraction of cellulose. A higher degree of crystallinity was observed for MCC obtained from corn HRs, which was attributed to a more efficient removal of lignin and hemicellulose by a higher sodium hydroxide concentration, which facilitates the dissolution of amorphous cellulose during acid hydrolysis. MCC obtained from HRs exhibited lower bulk density and poorer flow properties but similar or better tableting properties compared to commercial MCC (CeolusTM PH101). The lower ejection and detachment stress suggests that MCC isolated from HRs requires less lubricant compared to commercial MCC. This study showed that MCC isolated from wheat and corn HRs exhibits comparable tableting behaviour like commercial sample, further supporting this type of agricultural waste utilization.

Innovative Approaches for Manufacturing Epoxy-Modified Wood and Cellulose Fiber Composites: A Comparison between Injection Molding and 3D Printing.

The current study focused on improving the properties of polylactic acid (PLA) for wider application in load-bearing scenarios. Various methods were explored to optimize the interaction between PLA and natural fibers, particularly wood fibers (WFs). Alkalized and epoxy-impregnated WFs were evaluated against untreated WFs and cellulose fibers in both injection molding (IM) and fused deposition modeling (FDM). FTIR analysis revealed the removal of hemicellulose and lignin in alkalized WFs and uniform epoxy curing. Addition of fibers reduced PLA's thermal stability while acting as nucleating agents. Additionally, fibers augmented the storage modulus of biocomposites, with alkalized fibers exhibiting the highest tensile modulus in IM. FDM samples with a 0° raster angle showed superior impact resistance compared to IM counterparts. Moreover, raster angle significantly influenced FDM biocomposite properties, enhancing the tensile strength and modulus of untreated WF and cellulose fibers at 0°. Although FDM did not produce alkalized WF samples, epoxy impregnation emerged as a promising method for enhancing PLA/WF composite mechanical properties in the IM process, offering valuable insights for composite material development.