Search Results (61)

Depending on the feedstock type and the pyrolysis conditions, biochars exhibit different physical, chemical, and structural properties, which highly influence their performance in various applications. This study presents a comprehensive characterization of biochar materials derived from the waste wood of pine (Pinus sylvestris L.) and beech (Fagus sylvatica) after low-temperature pyrolysis at 270 °C, followed by chemical activation using zinc chloride. The resulting materials were thoroughly analyzed in terms of their chemical composition (FTIR), thermal behavior (TGA/DTG), structural morphology (SEM and XRD), elemental analysis, and particle size distribution. The successful modification of raw biomass into carbon-rich structures of increased aromaticity and thermal stability was confirmed. Particle size analysis revealed that the activated carbon of Fagus sylvatica (FSAC) exhibited a monomodal distribution, indicating high homogeneity, whereas Pinus sylvestris-activated carbon showed a distinct bimodal distribution. This heterogeneity was supported by elemental analysis, revealing a higher inorganic content in pine-activated carbon, likely contributing to its dimensional instability during activation. These findings suggest that the uniform morphology of beech-activated carbon may be advantageous in filtration and adsorption applications, while pine-activated carbon’s heterogeneous structure could be beneficial for multifunctional systems requiring variable pore architectures. Overall, this study underscored the potential of chemically activated biochar from lignocellulosic residues for customized applications in environmental and material science domains. Full article

Biodegradable polymer composites offer promising alternatives to petroleum-based plastics, supporting the principles of a zero waste and circular economy. This study investigates the reinforcing potential of alkali-treated wood flour derived from recycled pine (Pinus brutia Ten.) and poplar (Populus alba L.) waste wooden pallets in poly(lactic acid) (PLA) biocomposites. Wood flour was initially recovered through grinding and screening during recycling, followed by alkali treatment via a green chemistry approach to enhance interfacial bonding with the PLA matrix. The impact of alkali concentration and two fabrication methods—additive manufacturing (AM) and injection molding (IM)—on the properties of developed biocomposite materials was assessed through mechanical, physical, morphological, and thermal analyses. IM samples outperformed AM counterparts, with the IM PLA containing 30 wt% wood flour (alkali-treated with 10% solution) showing the highest mechanical gains: tensile (+71.35%), flexural (+64.74%), and hardness (+2.62%) compared to untreated samples. Moreover, the AM sample with 10 wt% wood flour and 10% alkali treatment showed a 49.37% decrease in water absorption compared to the untreated sample, indicating improved hydrophobicity. Scanning electron microscopy confirmed that alkali treatment reduced void content and enhanced morphological uniformity, while thermal properties remained consistent across fabrication methods. This work introduces a green composite using non-toxic materials and treatments, facilitating eco-friendly production aligned with zero waste and circular economy principles throughout the manufacturing lifecycle. Full article

Additive manufacturing (AM) has brought significant breakthroughs to the construction sector, such as the ability to fabricate complex geometries, enhance efficiency, and reduce both material usage and construction waste. However, several challenges must still be addressed to fully transition from conventional construction practices to innovative and sustainable green alternatives. This study investigates the use of non-cementitious traditional mixtures for green construction applications through 3D printing using Liquid Deposition Modeling (LDM) technology. To explore the development of mixtures with enhanced physical and mechanical properties, natural pine and cypress wood shavings were added in varying proportions (1%, 3%, and 5%) as sustainable additives. The aim of this study is twofold: first, to demonstrate the printability of these eco-friendly mortars that can be used for conservation purposes and overcome the challenges of incorporating bio-products in 3D printing; and second, to develop sustainable composites that align with the objectives of the European Green Deal, offering low-emission construction solutions. The proposed mortars use hydrated lime and natural pozzolan as binders, river sand as an aggregate, and a polycarboxylate superplasticizer. While most studies with bio-products focus on traditional methods, this research provides proof of concept for their use in 3D printing. The study results indicate that, at low percentages, both additives had minimal effect on the physical and mechanical properties of the tested mortars, whereas higher percentages led to progressively more significant deterioration. Additionally, compared to molded specimens, the 3D-printed mortars exhibited slightly reduced mechanical strength and increased porosity, attributable to insufficient compaction during the printing process. Full article

Wood waste, primarily composed of lignin, cellulose, and hemicellulose, which is typically disposed of through burning and crushing, poses environmental challenges. However, conventional wood waste disposal methods present critical limitations, such as environmental pollution and resource waste. To develop sustainable processing strategies to dispose wood waste, we identified two fungal isolates, SMF410-5-1 and ME1-1, from decayed wood trunks, demonstrating high lignocellulose-degrading enzyme activities, including laccase (Lac, 125.7 U/mL), manganese peroxidase (MnP, 89.3 U/mL), and lignin peroxidase (LiP, 67.9 U/mL). Isolates of ME1-1 and SMF410-5-1 both exhibited superior poplar lignin degradation, while SMF410-5-1 excelled in coniferous wood weight losses, which reached 19.7% for pine after 180 days post inoculation. Moreover, biochemical analyses revealed that isolates of ME1-1 and SMF410-5-1 accelerated the degradation by producing various lignocellulose-degrading enzymes to hydrolyze wood waste. In addition, through multi-locus phylogenetic analysis using sequences of the internal transcribed spacer (ITS), large subunit ribosomal RNA (LSU), and RNA polymerase II second largest subunit (RPB2), SMF410-5-1 and ME1-1 were identified as Phlebia formosana and Auricularia cornea, respectively. This study provides novel insights into fungal-driven biodegradation, offering eco-friendly solutions for forest waste recycling and supporting circular bioeconomy strategies. Full article

Waste production is a worldwide concern due to its adverse impact on the environment, as well as on the health of living beings. Sustainable development states the urgent need to implement actions to gradually replace fossil resources, including the use of renewable raw materials such as residues and secondary raw materials from other industries as a promising alternative to replace fossil resources. This research explores an approach focused on the design of renewable materials by developing a bio-based textile coating with the use of sawdust from radiata pine, which is the result of industrial wood transformation processes. The methodology adopted a transdisciplinary approach, integrating knowledge from design, engineering, and sociology disciplines. A perceived sawdust quality study was carried out in its original format, while two different coated textile substrates were developed, using knife-over-roller and spray coating processes, which were evaluated from user acceptance and functional performance points of views. Finally, a clothing prototype for workwear, using the bio-based coatings, was developed, employing a mono-material design concept (i.e., using the same material in all its forms). The results obtained from users and laboratory studies favour the knife-over-roller coating and the removable clothing design, which provides improved usability performance. The obtained conclusions highlight that transdisciplinary collaboration is essential to address complex challenges in the development of solutions, placing the design of material as a necessary prior action in the design process of final products. Full article

Biomass carbon foams are extensively utilized across various fields due to their favorable properties and cost-effectiveness. In this study, triethylene glycol (TEG), nylon 66 (PA66), and 3-glycidyl-oxypropyl-trimethoxy-silane (KH560) were incorporated into pine wood liquefaction resin to successfully prepare three novel modified carbon foams (MCFs), and their characteristics were investigated. The results indicate that the compressive strength and specific surface area of the three MCFs were significantly enhanced. Specifically, the compressive strength increased by 37%, 46%, and 89% following modification with TEG, PA66, and KH560, respectively, while the specific surface areas ranged from 383.4 to 499.3 m²/g. Additionally, the cell structures of the three MCFs exhibited greater uniformity, with larger average pore sizes, thinner ligament thicknesses, and increased opening porosities. Notably, the opening porosity of KH560-modified carbon foam (KH560-PLP-PF-CF) reached its maximum value at 87.95%. XPS analysis confirmed the successful introduction of Si-containing molecular bonds, including Si-OH-Si, Si-OH, and Si-CH, into KH560-PLP-PF-CF. Furthermore, FT-IR analysis revealed characteristic Si-O vibration peaks, PA66 amide peaks, and TEG ether bond absorption peaks in the three MCFs. The incorporation of flexible functional groups effectively enhanced their compressive properties. The findings of this study expand the potential for utilizing biomass waste to partially replace phenol in the development of novel carbon foams. Full article

The aim of this paper is to carry out a rheological study of the pressing of pine wood sawdust, after which obtaining briquettes from the same wood material with a hydraulic installation and analyzing their properties. In order to know the rheological behavior during pressing, the fractions resulting from sorting the sawdust with 4 × 4, 3 × 3, 2 × 2, and 1 × 1 mm² sieves were used, respectively, six fractions (the fraction larger than 4 × 4 mm² and the smaller one of 1 × 1 mm² are added) and a specific pressing device, placed on a universal testing machine. The results obtained in the rheological study showed that the obtained density does not increase proportionally with the pressure, the best results (density of 1030 kg/m³) being obtained at a pressure of 180 MPa. Within the briquettes, higher densities were obtained for the sawdust fraction smaller than 1 × 1 mm², but the breaking strength was higher for the fraction larger than 4 × 4 mm². As a general conclusion, it was found that pine sawdust is easily compressible, and the briquettes obtained from it have good properties for use in combustion. Full article

Given the construction challenges and the impacts of industrial waste generation and the implications of using chemical adhesives, this study aims to evaluate epoxy as an alternative resin, whose application in the production of wood particleboards is still underexplored. In this regard, its results were compared with those of widely used adhesives, such as urea-formaldehyde (UF). Pine wood particles were used, and epoxy resin was applied as a binder in 5%, 10%, and 15% proportions. Panels were manufactured under pressing parameters of 5 N/mm² for 10 min at 110 °C. Physical and mechanical properties of panels were evaluated using Brazilian, European, and American standards. The results showed that epoxy resin is potentially convenient for the particleboard industry, as the 15% trait panels met the P4 class criteria in the Brazilian and European standards and D-2 for the American code, and the 10% trait panels achieved the M-3i class for the American document. Although 5% adhesive was insufficient to envelop wood particles, these traits with greater percentages reached high enveloping ratings in the scanning electron microscopy (SEM) test, making epoxy resin viable for the panel industry as a potential alternative to formaldehyde-based adhesives. Full article

The use of low-cost agricultural and forestry waste for the preparation of modified phenolic foam (MPF) has attracted widespread attention and has shown promising prospects. This study proposes a novel method for producing MPF using pine sawdust. The full components of pine wood powder and its liquefied products were used as raw materials, and the resin was modified with a silane coupling agent (KH560), triethylene glycol (TEG), and nylon 66 (PA66). Subsequently, three novel MPFs were successfully fabricated using a transplanted core foaming technique, and their material properties were subsequently investigated. The results showed that all three MPFs exhibited excellent compressive strength and flame retardancy, with compressive strength ranging from 5.93 MPa to 12.22 MPa and oxygen index values between 36.2% and 41.5%. In terms of water resistance, the MPFs significantly outperformed traditional phenolic foam (PF); in particular, the addition of 4% KH560 and PA66 reduced the water absorption rate to as low as 2.5%. Furthermore, the powdering rate and thermal conductivity of all MPFs were significantly reduced, with chalking rates decreasing by 28.57% to 50%. This research presents a novel method for preparing MPF using agroforestry waste as a partial replacement for phenol. This approach achieves high-value utilization of pine sawdust while maintaining the performance of the MPF, thus broadening the avenues for MPF production. Full article

The paper presents the mechanical and hygrothermal properties of cement mortars containing bio-powders made from lavender waste and black pine wood. The wastes were mechanically ground with a hammer mill to a fraction not exceeding 0.5 mm and then dried in air-dry conditions. The influence of bio-additives in amounts of 1.5% and 2.5% of the overall mortar volume was tested. The aim of the paper was to determine the impact of bio-additives on the mechanical and hygrothermal properties of the tested cement mortars. This publication included tests of compressive and flexural strength, elastic modulus, water absorption, absorption due to capillary rise, sorption and desorption properties, thermal properties, microstructural tests using mercury intrusion porosimetry and SEM, and EDS. The main conclusions of the research indicate that mortars with both 1.5% and 2.5% bio-powders are characterized by strong bactericidal properties, lower sorption properties at high air humidity, lower thermal conductivity, reduced compressive strength by 22–27%, no significant effect on the flexural strength, and significant reduction in capillary action of mortars both with short-term and long-term water exposure. Full article

Thermogravimetric analysis (TGA) was performed on six samples of pine wood, poplar sawdust and olive residue, and the kinetic parameters were evaluated by using isoconversional models. The hemicellulose, cellulose and lignin contents were also estimated using the Fraser–Suzuki deconvolution method. In addition, a range of thermodynamic parameters and combustion indices was calculated. Significant correlations were found between the kinetic, thermodynamic and combustion parameters. The ignition index showed an inverse relationship with the activation energy, whereas the burnout index correlated with enthalpy values for most samples. Higher heating rates during TGA increased ignition and combustion efficiencies but decreased combustion stability. Differences in behaviour were detected between the olive residues, which had a much higher lignin content (51.2–56.9%), and the woody biomass samples (24.2–29.2%). Moreover, the sample with the highest ash content also exhibited some distinctive characteristics, including the lowest high heating value and ignition index, coupled with the highest activation energy, indicating a less favourable combustion behaviour than the other samples. The particle size of the samples was also found to be critical for both combustion efficiency and safety. Full article

Diverse types of waste are generated during the sawmilling process. One of them is pine wood shavings (PWSs). This waste can be transformed by pyrolysis into biochar (BC) to produce a sustainable material that can serve as an asphalt binder modifier. In this study, a BC produced with PWS as biomass (BC-PWS) was used to modify the properties of an asphalt cement (AC). This type of BC has not been investigated as a modifier of ACs and asphalt mixtures. Three BC-PWS contents were used for this purpose (BC/AC = 5, 10, and 15% by weight). Conventional characterization tests such as penetration, softening point, and rotational viscosity were performed on the unmodified and modified ACs. Rheological properties were also evaluated at high and intermediate temperatures, and observations were made with a scanning electron microscope (SEM). The modified BC/AC = 10% binder was chosen to manufacture a hot-mix asphalt (HMA). Marshall, indirect tensile strength—ITS, Cantabro, resilient modulus (RM), permanent deformation, and fatigue resistance (under stress-controlled mode) tests were performed on the HMA. The Tensile Strength Ratio (TSR) parameter was determined from ITS tests. BC-PWS is a promising material as an AC modifier from the technical-environmental point of view, which tends to enhance the evaluated properties of AC and HMA (monotonic load, rutting, fatigue, moisture damage, and raveling resistance), without resorting to increases in asphalt content or increases in mixing and compaction temperatures. Full article

This study explores the use of pine wood biochar (BC) waste gasified at 950 °C as fillers in polymer matrices to create BC@biopolymer composites with perspectives in groundwater remediation. Four biochar samples underwent different sieving and grinding processes and were extensively characterized via UV–Vis, FTIR, and FESEM–EDS, highlighting the fact that that BCs are essentially graphitic in nature with a sponge-like morphology. The grinding process influences the particle size, reducing the specific surface area by about 30% (evaluated by BET). The adsorption performances of raw BC were validated via an adsorption isotherm using trichloroethylene (TCE) as a model contaminant. A selected BC sample was used to produce hydrophilic, stable polymer composites with chitosan (CS), alginate (ALG), potato starch (PST), and sodium carboxymethylcellulose (CMC) via a simple blending approach. Pilot sedimentation tests over 7 days in water identified BC@PST and BC@CMC as the most stable suspensions due to a combination of both hydrogen bonds and physical entrapment, as studied by FTIR. BC@CMC showed optimal distribution and retention properties without clogging in breakthrough tests. The study concludes that biopolymer-based biochar composites with improved stability in aqueous environments hold significant promise for addressing various groundwater pollution challenges. Full article

The need, or even the obligation, to take care of the natural environment compels a search for new technological solutions, or for known solutions to be adapted to new applications. The maxim is ‘don’t harm, but improve the world for future generations’. In the wood industry in particular, given that it is based on a natural raw material, we must look for ecological solutions. Trees grow, but the demand for wood exceeds the volume of tree growth. In industrial manufacturing, one of the ways to make full use of wood is through chipless processing, which occurs during rotary cutting (peeling). In addition, wood is a natural material, each fragment of which has a range of properties. In addition, wood defects in quality manipulation generate a lot of waste. The aim of this study was to analyse the quality effect of the tested layered composites for flooring materials on production application. The practical purpose was to exchange actual sawing-based production for chipless production. The composite base layers were made of pine wood (Pinus L.) veneers with differing quality classes. The samples were subjected to three-point bending tests to calculate the moduli of elasticity and stiffness, which are the most important parameters. Because both analysed parameters describe product quality, the analyses were based on the creation of Shewhart control charts for each parameter. In theory, these control charts are tools for analysing whether the production process is stable and yields predictable results. To have full control over the process, five elements have to be applied: central line (target), two types of control lines (upper and lower) and two types of specification lines (upper and lower). New types of layered composites for flooring may be applied to production once verified using Shewhart control charts. It turns out that it is possible to produce the base layer of the flooring materials using the rotary cutting (peeling) method without having to analyse the quality of the raw material. This is a way to significantly increase the efficiency of production in every element of manufacturing. Full article

Carbon nanofibers based on lignin from wood waste have a promising potential for the ability to produce electrodes that can modernize existing energy storage technology. The most important detail is that the low cost, as well as the availability of the initial products for the production of lignin, will reduce the cost of energy storage devices and contribute to improving the environment. In this study, pine sawdust and elm sawdust were used as raw materials for the production of lignin, which accumulate in large quantities in metal workshops in Almaty. Lignin extraction was carried out using an organosolvent method, which is environmentally friendly, low-cost, uses minimal amounts of strong acids and metal catalysts, does not pollute water, and does not emit sulfur dioxide (SO₂). A comprehensive study of the characteristics of the obtained lignins from wood waste was carried out. Infrared spectroscopy (IR) revealed that the obtained lignin contains aromatic, phenolic, hydroxyl, methyl, and methoxyl groups. The results of nuclear magnetic resonance (NMR) spectroscopy showed the presence of a high number of syringyl (S) links compared to guaiacyl (G), which contribute to increased efficiency in the thermal processing of lignin. Also, this study investigated the use of the obtained lignins to produce continuous fibers by electrospinning. The effect of lignin mass on the viscosity of the lignin/polyacrylonitrile (PAN) solution and the effect of the carbonization temperature on the physico-chemical characteristics of the lignin/PAN solution were investigated. The following research methods were used for this purpose: Raman spectroscopy, thermogravimetric analysis (TGA), electron scanning microscopy, energy dispersion analysis, IR, NMR, and optical microscopy. The conditions for the production of lignin-containing carbon fibers at temperatures of 800, 900, and the carbonation heating rate, is an important parameter in the production of carbon fibers as it strongly affects the characteristics of the resulting carbon fibers. The heating rate affects were studied, and it was found that, at a heating rate of 5 °C/min and a carbonation temperature of 800 °C, porous carbon nanofibers with a diameter of 47 nm are formed in a nitrogen medium for 60 min. Full article