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Ball milling is a widely studied technique known for its effectiveness in processing lignocellulosic materials and generating nanocellulose. However, the importance of fiber swelling in facilitating the extraction of microfibrillated cellulose through ball milling remains largely unexplored. Here, we delve into the influence of ball milling on the morphological traits of cellulosic fibers with different water contents and their fibrillation. The introduction of water into the system disrupts both inter- and intra-molecular hydrogen bonds within the fiber microstructure, leading to rapid replenishment and water-fiber interactions that promote fiber swelling. Notably, softwood-derived bleached kraft pulp fibers, distinguished by their greater length compared to hardwood-derived counterparts, exhibit superior swelling potential while preserving fiber morphology. After 24 hours of ball-milling swollen fibers with a 90 % water content, the proportion of short fibers (<0.4 mm) increase significantly to 65.3 %, a substantial 42.7 % enhancement compared to non-milled fibers. Extended ball milling durations further improve transparency and mechanical strength of microfibrillated cellulosic network (paper). Transmittance at 550 nm reaches 85.3 % relative to ball milling for 24 hours, while mechanical tensile strength reaches 47.4 MPa relative to ball milling for 12 hours, a 144.3 % increase compared to non-milled fibers (19.4 MPa). These findings highlight the critical role of fiber swelling in enabling efficient mass production of high-quality microfibrillated cellulose via ball milling, presenting promising avenues for commercial-scale production across diverse value-added applications. • Fiber swelling in softwood pulp via ball milling boosts microfibrillated cellulose. • Crucial water disruption enhances fiber swelling via hydrogen bonds. • Water content decisively shapes cellulosic particle morphology during milling. • Promising commercial-scale potential across versatile applications. [ABSTRACT FROM AUTHOR]

Cellulose is an organic compound belonging to polysaccharides. This biopolymer is made of glucose subunits. This compound plays an essential role in the structure and strength of plants. This polymer has biodegradable, biocompatible, and renewable properties. Agricultural wastes are excellent sources for cellulose extraction. Agricultural wastes are lignocellulosic materials, and cellulose and lignin are the main components of these wastes. Millions of tons of agricultural waste are thrown away and burned yearly. This large amount of waste leads to environmental pollution and waste of renewable energy resources. Upgrading such waste by developing innovative products such as cellulose nanomaterials and nanocomposites can have high environmental and economic benefits. The intelligent use of agricultural waste as a rich source of cellulose can be primarily responsible for the increase in population and industrialization of countries. Optimal cellulose extraction from agricultural waste can be widely used in various fields of agriculture, industry, medicine, and energy. Different chemical, physical, physicochemical, and biological methods have been presented to extract cellulose and its derivatives from agricultural waste. In this review, we will discuss the position and importance of cellulose, the importance of agricultural waste in the extraction of cellulose, and the use of extracted cellulose from agrarian wastes in various sources. • Agricultural wastes as an excellent source for cellulose extraction. • The use of agricultural waste intelligently to extract cellulose and use it in various industries. • Cellulose extracted from agricultural waste as a natural biocompatible and degradable polymer can greatly interest agriculture. [ABSTRACT FROM AUTHOR]

The present work provides a comprehensive study on the utilization of rapeseed stalks, an agricultural waste, as a raw material for the production of resin-free fiberboards and particleboards, using LCNFs as binder. The rapeseed stalks underwent appropriate crushing and fibrillation and were combined with a novel class of lignocellulosic nanofibers (LCNFs) derived from date palm waste, another agricultural residue. The incorporation of LCNFs in both fiberboards and particleboards resulted in increased density and enhanced mechanical properties, dimensional stability, and fire resistance. These positive effects can be attributed to several factors. Firstly, the incorporation of LCNFs led to a reduction in porosity, positively impacting the modulus of rupture, modulus of elasticity, and internal bonding of the produced fiberboards and particleboards. Notably, fiberboards containing 15 wt% LCNF exhibited superior specific properties compared to our commercial reference. Additionally, this densification effect mitigated moisture absorption and thickness swelling, as even a 2 wt% incorporation of LCNF in fiberboards showed reduced values for both properties. Secondly, the high lignin content of the LCNFs contributed to decreased hydrophilicity in the fiberboards and particleboards, leading to significant improvements in water contact angle, water absorption, and thickness swelling. Lastly, the increased density of the fiberboards and particleboards resulted in improved fire resistance, with flame propagation time being higher for all boards containing LCNFs, even at low content (2 wt%), compared to the commercial fiberboard. Notably, fiberboards demonstrated superior performance compared to particleboards, attributed to factors such as low cohesion, particle heterogeneity, and excessive porosity. Overall, this study demonstrates the feasibility of utilizing agricultural waste as a raw material for board production, eliminating the need for urea-formaldehyde resins and paraffin waxes commonly found in commercial fiberboards. [Display omitted] • Fiber- and particleboards from rapeseed stalks and date palm wastes were produced. • LCNFs provided improved mechanical performance and dimensional stability. • Fire retardancy of fiberboards was better than the commercial reference. • Density plays a key role in the main properties of particleboards and fiberboards. • Lignin from LCNFs were determinant in the hydrophobization and fire retardancy. [ABSTRACT FROM AUTHOR]

The cleaning of water polluted by toxic geogenic compounds is challenging and demands novel, sustainable and low-cost adsorbents. To address this environmental problem, agricultural wastes functionalized with lanthanum have been studied for the depollution of arsenate and fluoride in aqueous solution. A simple and straightforward approach was utilized to anchor lanthanum on the surface of avocado seed, cauliflower stem, and macadamia nut shell wastes with the aim of effectively removing these toxic water pollutants and avoiding the microorganism growth on the biomass and its degradation during prolonged equipment operation. The adsorption mechanism using these modified biomass samples was endothermic and multi-ionic, involving up to two arsenate and three fluoride ions that can interact with the biomass surface functionalities. The simultaneous adsorption of these pollutants was antagonistic, and the co-anion concentration inhibited the adsorption of target geogenic pollutants. Overall, the fluoride adsorption properties of these modified lignocellulosic wastes were better than those for arsenate. The antibacterial activity of the lanthanum-modified biomass samples may enable for their use in packed-bed columns for long-term water treatment processes. The adsorption and antimicrobial properties of these functionalized biomass residues are promising for the implementation of efficient and economic processes for purifying water contaminated by arsenate and fluoride. [Display omitted] • Lanthanum-functionalized biomass wastes removed arsenate and fluoride from water. • Simultaneous fluoride and arsenate adsorption was antagonistic. • Cauliflower stems functionalized with lanthanum was the best adsorbent. • Lanthanum-functionalized biomass wastes showed antibacterial properties. [ABSTRACT FROM AUTHOR]

Various pretreatment techniques can change the physical and chemical structure of lignocellulosic biomass and improve the hydrolysis rates. High-intensity ultrasound could be a promising technique in the biomass pretreatment process. The objective of this work was to study the effect of biomass concentration, pH, ultrasonic power level and sonication time on the production yield in total sugars (S T ) and reducing sugars (S R ) during the pretreatment of banana flower-stalk biomass. A qualitative evaluation was carried out by scanning electron microscopy, showing a disruptive effect on the biomass structure at high ultrasonic power levels and low biomass concentrations. An experimental design with three-levels for the four-variables was used in order to set the conditions for the pretreatments. Stepwise regression (SRG) and an artificial neural network (ANN) were applied in order to establish mathematical models that could represent and be used to study the dependence of the factors on both the S T and S R yields. The statistical results indicated that the ANN approach provided a more accurate estimation than SRG. [ABSTRACT FROM AUTHOR]

During the pretreatment of lignocellulosic biomass for second generation bioethanol production, fermentation inhibitors are released. To overcome this, the use of a robust industrial strain together with agro-industrial by-products as nutritional supplementation was proposed to increase ethanol productivity and yields. Two factorial experimental designs were carried out to optimize fermentation of hydrolysate from autohydrolysis of Eucalyptus globulus . The most influential variables on ethanol production were cheese whey and K 2 O 5 S 2 (potassium metabisulfite) supplementation. Nutrient addition effect was demonstrated using the whole slurry from autohydrolysis in two process configurations (separate hydrolysis and fermentation, SHF and simultaneous saccharification and fermentation, SSF). Comparing the supplemented SHF and SSF assays with non-supplemented, 2.3 and 7.4 fold higher ethanol concentrations were obtained, respectively. In the case of SSF, 50.4 g L −1 of ethanol concentration and 92.2% of ethanol conversion were attained, demonstrating an improved fermentation performance in industrial lignocellulose fermentations. [ABSTRACT FROM AUTHOR]

Highlights: [•] Dilute-acid pretreatment of Jatropha curcas shells for enzymatic hydrolysis was assessed. [•] Cellulose conversions above 80% were achieved in the enzymatic hydrolysis. [•] Optimal conversion was predicted for pretreatment at 136°C, 30min and 1.5% H2SO4. [•] Water extraction prior to pretreatment was found to further improve the enzymatic conversion. [ABSTRACT FROM AUTHOR]

Abstract: In this work, dilute sulphuric acid prehydrolysis of residual empty pods of Moringa oleifera fruits was investigated as pretreatment for enzymatic hydrolysis of cellulose. In experiments performed at 130–190°C for 10–30min, corresponding to a severity range between log R o =1.9 and log R o =4.2, the effect of pretreatment conditions on the recovery of polysaccharides and on the enzymatic convertibility of cellulose was evaluated. Overall cellulose recovery was above 95% in the pretreatments performed at 130 and 160°C, and between 87 and 90% in the pretreatments at 190°C, while xylan recovery in the most severe pretreatments was only 24.7–50.2%. The highest sugar concentration in the acid prehydrolysates (15.0g/L) was obtained in the pretreatment performed at 160°C and 20min. The formation of degradation products was low at mild pretreatment conditions, but it increased with the severity. Furfural concentration reached 4.04g/L at log R o =3.1 and decreased again with a further increase of the pretreatment severity. HMF, formic acid and levulinic acid were formed only in the most severe pretreatments. The pretreatment was effective for improving the enzymatic hydrolysis of cellulose, and the highest conversion (84.3%) was achieved in the material pretreated at mid severity (log R o =3.1). [Copyright &y& Elsevier]

• High-quality boards can be produced from alternative lignocellulosic raw materials. • Panels made from alternative materials meet the requirements for panels of type P2. • New raw materials should be focused on plants that are already grown for various purposes. • Alternative raw materials may limiting wood harvesting for panels production. One way to reduce the use of wood resources and simultaneously to manage wastes in the form of forest and agricultural biomass, as well as biomass originating from the food processing industry, is to use those wastes in particleboard production as an alternative raw material to wood chips. This article highlights the potential of woody biomass from non-forest sources. Based on a review of the current scientific literature, an attempt is made to identify the raw materials with the greatest potential, considering their availability and the quality of boards made from them. Suggestions are also made regarding the search for new raw materials, based on their production potential. [ABSTRACT FROM AUTHOR]