Search Results (95)

Packaging demand currently exceeds 144 Mt per year, of which >90% is conventional plastic, generating over 100 Mt of waste and 1.8 Gt CO₂-eq emissions annually. In this review, we systematically survey three classes of lignocellulosic feedstocks, agricultural residues, fruit and vegetable by-products, and forestry wastes, with respect to their physicochemical composition (cellulose crystallinity, hemicellulose ratio, and lignin content) and key processing pathways. We then examine fabrication routes (solvent casting, extrusion, and compression molding) and quantify how compositional variables translate into film performance: tensile strength, elongation at break (4–10%), water vapor transmission rate, thermal stability, and biodegradation kinetics. Highlighted case studies include the reinforcement of poly(vinyl alcohol) (PVA) with 7 wt% oxidized nanocellulose, yielding a >90% increase in tensile strength and a 50% reduction in water vapor transmission rate (WVTR), as well as pilot-scale extrusion of rice straw/polylactic acid (PLA) blends. We also assess techno-economic metrics and life-cycle impacts. Finally, we identify four priority research directions: harmonizing pretreatment protocols to reduce batch variability, scaling up nanocellulose extraction and film casting, improving marine-environment biodegradation, and integrating circular economy supply chains through regional collaboration and policy frameworks. Full article

This study evaluates the structural properties and adsorption capacities of four bio-based adsorbents, sawdust (SD), straw (ST), chicken feathers (CFs), and shrimp shells (SSs), for chemical oxygen demand (COD) removal from olive mill wastewater (OMW). Response Surface Methodology (RSM) with a Box–Behnken Design (BBD) was applied to optimize the operational parameters, resulting in maximum COD uptake capacities of 450 mg/g (SD), 575 mg/g (ST), 700 mg/g (CFs), and 750 mg/g (SSs). Among these materials, SSs exhibited the highest COD removal efficiency of 85% under optimal conditions (pH 8, 20 g/L, 30 °C, 5 h, 111 rpm). A mixture design approach was then used to explore the synergistic effects of combining lignocellulosic (SD and ST), chitin-based (SSs), and keratin-based (CFs) adsorbents. The optimized blend (SD 10%, ST 28.9%, SS 38.3%, and CF 22.6%) achieved a COD removal efficiency of 82%, demonstrating the advantage of using mixed biopolymer systems over individual adsorbents. Adsorption mechanisms were investigated through isotherm models (Langmuir, Freundlich, Temkin, and Redlich–Peterson) and kinetic models (pseudo-first-order, pseudo-second-order, Elovich, and intraparticle diffusion). Lignocellulosic adsorbents predominantly followed physisorption mechanisms, while chitin- and keratin-rich materials exhibited a combination of physisorption and chemisorption. Thermodynamic analysis confirmed the spontaneous nature of the adsorption process, with SSs showing the most favorable Gibbs free energy (ΔG = −21.29 kJ/mol). A proposed mechanism for the adsorption of organic compounds onto the bio-adsorbents involves hydrogen bonding, electrostatic interactions, π–π interactions, n–π stacking interactions, hydrophobic interactions, and van der Waals forces. These findings highlight the potential of biopolymer-based adsorbents and their optimized combinations as cost-effective and sustainable solutions for OMW treatment. Full article

The environmental impact of petroleum-based plastics has driven a global shift toward sustainable alternatives like biodegradable polymers, including polylactic acid (PLA), polybutylene succinate (PBS), and polycaprolactone (PCL). Yet, these bioplastics often face limitations in mechanical and thermal properties, hindering broader use. Reinforcement with cellulose nanofibrils (CNFs) has shown promise, yet most research focuses on conventional sources like wood pulp and cotton, neglecting agricultural residues. This review addresses the potential of maize husk, a lignocellulosic waste abundant in South Africa, as a source of CNFs. It evaluates the literature on the structure, extraction, characterisation, and integration of maize husk-derived CNFs into biodegradable polymers. The review examines the chemical composition, extraction methods, and key physicochemical properties that affect performance when blended with PLA, PBS, or PCL. However, high lignin content and heterogeneity pose extraction and dispersion challenges. Optimised maize husk CNFs can enhance the mechanical strength, barrier properties, and thermal resistance of biopolymer systems. This review highlights potential applications in packaging, biomedical, and agricultural sectors, aligning with South African bioeconomic goals. It concludes by identifying research priorities for improving compatibility and processing at an industrial scale, paving the way for maize husk CNFs as effective, locally sourced reinforcements in green material innovation. Full article

Lignocellulosic biomass is a sustainable renewable resource for producing biopolymers, chemicals, and high-value compounds. This study proposes a biomass valorization concept that combines hydrodynamic cavitation (HC) and hydrothermal separation (HTS) to produce high-value products. Aspen Plus software was used in this study to develop the first simulation-driven integration of HC and HTS for biomass valorization in the biorefinery concept. The overall separation efficiency and component yield for standalone HC and HTS processes agreed with the experimental data. The findings from the simulation results indicate that the coupled processes yielded a significant enhancement in overall separation efficiency. This coupling resulted in a 24.5% increase compared to a single HC process and 16.75% higher efficiency than a single HTS process for sugarcane bagasse. The sensitivity analysis showed that incrementing HTS temperature and reaction time results in higher component yield and overall separation efficiency. The increase in the S/L ratio demonstrated a higher component yield in the process downstream, whereas the efficiency remained approximately the same. The effect of the HTS pressure was negligible on component yield and overall separation efficiency. Moreover, this study identified the optimal process parameters of the coupled process. At the optimal condition, quadratic models showed an overall separation efficiency of 79.41 ± 2.71% for the HC-HTS coupled process. This approach promises superior biomass utilization over traditional processes, minimizing waste and environmental impact while expanding the potential applications of biomass. Full article

The aim of this scoping review is to investigate the potential development of an alternative material derived from renewable biological resources such as goldenberry calyx and modified cassava starch as the matrix. Moreover, this paper reviews the impact of combining starch and lignocellulosic fiber on improving the properties of bioplastic materials. The goldenberry calyx is a type of lignocellulosic waste with a low moisture content, which offers logistical advantages, as a high moisture content can accelerate waste deterioration. However, studies on the utilization of goldenberry calyx are scarce. In addition, due to its low cost and availability, starch is the main polysaccharide for biofilm development as a matrix. Combining these two materials can result in a composite material with suitable and adequate properties for packaging applications, although no studies have been published on this specific combination. Starch and lignocellulosic fiber are complementary as the properties of starch biopolymers improve when a hydrophobic material (lignocellulosic fibers) is incorporated. Moreover, starch strengthens fibers by enhancing their biodegradability through its water absorption capacity. In this study, modified cassava starch, with its higher amylose content, is suggested for use, as the proportion of amylose correlates with enhanced bioplastic properties. Full article

Nut by-products, particularly shells, are a globally abundant agricultural residue. Their widespread accumulation poses a serious environmental challenge. However, nut shells are of great interest due to their inherent lignocellulosic composition. For instance, they are rich in cellulose, a high-value biopolymer widely used in the production of bio-based materials. Therefore, this review critically analyses conventional and novel pre-treatment strategies for the extraction of cellulose from nut shells, emphasising the importance of optimising valorisation routes to minimise ecological impact. Various techniques—ranging from alkaline treatments to emerging approaches such as deep eutectic solvents and hydrothermal methods—have been examined and compared. The findings in cellulose purification through different strategies reveal that, while some methods are promising, others remain underexplored. Emphasis is placed on the necessity of comprehending the specific structural and chemical characteristics of each type of nut shell; as such, knowledge is fundamental to understanding the efficiency of the applied methods. This review highlights the growing interest in the valorisation of nut shell by-products as promising lignocellulosic resources of significant utility. Therefore, it also reveals the need for further research, focusing on process scalability, cost-efficiency, and environmental impact. Advancing in these areas is essential to enable the transition of nut shells from waste to a highly valuable resource. Full article

The growth of plants highly depends on the soil’s water availability and properties. Hydrogels (HGs) have been used for decades to enhance soil water retention, whereas developing eco-friendly and sustainable HGs for agricultural applications is still necessary to ensure water and food security. In this study, renewable and cost-effective HGs were prepared from all-lignocellulose fibers of date palm biomass after carboxymethylation followed by citric acid (CA) crosslinking. HGs showed high equilibrium swelling capacity (EWC%), even in salty media, whereas purified HGs showed about 700–400 EWC% in deionized water. Further, HGs’ effect on germination was studied on Chico III tomato, mint, Basilico red, and chia seeds. The results revealed that HGs enhanced the soil properties, with taller and healthier plants observed in HG-amended soil. FTIR, thermal analysis, and microscope imaging were utilized to evaluate HGs’ and raw materials’ characteristics. The findings in this study support the idea that all-lignocellulose could be used for HG production without separation. Full article

This review discusses the potential of emerging technologies, as well as their integration with conventional methods, to optimize the extraction of lignocellulosic compounds from cocoa pod hull (CPH), an agro-industrial residue that represents approximately 76% of the total weight of the fruit. CPH is primarily composed of cellulose, hemicellulose, lignin, and pectin. Emerging technologies such as microwave-assisted extraction, hydrothermal treatment, subcritical water, ionic liquids, deep eutectic solvents, and ultrasound treatment have proven effective in recovering value-added compounds, especially when combined with conventional techniques to improve process efficiency. Furthermore, the use of technologies such as high-voltage electric discharge (HVED) is proposed to reduce inorganic contaminants, such as cadmium, ensuring the safety of by-products. The CPH compounds’ applications include use in the food, pharmaceutical, cosmetics, agricultural, biopolymer, and environmental industries. The conversion of CPH to biochar and biofuels via pyrolysis and supercritical extraction is also discussed. The integration of technologies presents an opportunity to valorize CPH and optimize by-product development; however, as research continues, process scalability and economic viability must be assessed. Full article

During the conventional biomass fractionation, the degradation and dissolution of lignin and hemicellulose result in a complex extract which remains very challenging for the thorough separation and purification of a wide variety of fractionated products, limiting their further utilization. Herein, we proposed a facile and efficient strategy for fractionating biomass and simultaneously in situ converting of both lignin and hemicellulose into single products using a formic acid–phloroglucinol system. The introduced phloroglucinol could react with lignin fragments and hemicellulose-derived products, and the generated intermediate product from hemicellulose can be further condensed with lignin fragments, finally forming single lignin-based functional biopolymers containing heterocyclic structures. Only small amounts of hemicellulosic derivatives, such as oligosaccharides, monosaccharides, furfural, and 5-HMF, were detected in the extracted solution, indicating a highly directional and effective in situ conversion process of hemicellulose. The constructed specific structures on fabric surfaces by using the chelation between lignin-based functional biopolymers and metal ions achieved the preparation of functional fabrics with stable hydrophobicity. The dynamic contact angle of water droplets on the surface of prepared fabric only decreased from 122° to 116.8° over 30 min. This work strategy provides an ideal route to maximize the utilization of both lignin and hemicellulose without involving complex separation and purification procedures. This strategy is the first demonstration of using the targeted fractionation system to achieve the simultaneous conversion of hemicellulose and lignin into single functional biopolymers directly from lignocellulosic biomass. Full article

The enhanced use of wood residues from the timber industry contributes to mitigating the global climate crisis. Currently, bark, a by-product of the timber industry, is primarily burned for thermal energy generation. However, with the growing demand for lignocellulosic products and the emphasis on extending life cycles, it would be more beneficial to prioritize substantial uses of bark over thermal utilization. Although numerous methods for substantial bark utilization have been explored, a significant untapped potential remains. The extractives obtained through water extraction, for instance, can be applied to various further uses like biopolymers or medical applications. This study investigates the impact of hot water extraction on the mechanical and physical properties of bark-based panels, with the aim of extending the life cycle of tree bark and its valorization in bio-based composites. The findings demonstrate that hot water extraction can enhance the bending properties (modulus of rupture, modulus of elasticity) of bark-based panels. Additionally, the extractives obtained from the process have potential applications in the pharmaceutical and adhesive industries. The study also includes an LCIA that highlights the differences between the three scenarios addressed in this research, namely energy generation from bark-based biomass, extraction of bark, and use of extracted bark residues in the production of bark-based particleboard. Full article

Environmental pollution and the accumulation of industrial waste are increasingly serious issues that impose financial burdens on businesses and pose threats to ecosystems. As industrial production continues to grow, the volume of waste generated by humanity is rising, leading to a heightened need to search for effective waste management and recycling methods. One promising approach is the concept of a circular economy, where industrial waste, including agricultural and food processing waste, is transformed into new products. The goal is to maximize the utilization of natural resources, particularly in food production. This article presents various concepts for utilizing specific types of plant-based waste, particularly lignocellulosic, pectin, and starch wastes, in biotechnological processes aimed at producing value-added food ingredients with a technological function. The literature clearly shows that this waste can be effectively used in the cultivation of different microorganisms to produce enzymes, polyols, oligosaccharides, carboxylic acids, and biopolymers, among other products. However, further research is needed to explore more efficient and environmentally friendly methods, especially in the utilization of lignocellulose in biotechnology. This research shows knowledge gaps in existing discussed solutions. Full article

In line with environmental awareness movements and social concerns, the textile industry is prioritizing sustainability in its strategic planning, product decisions, and brand initiatives. The use of non-biodegradable materials, obtained from non-renewable sources, contributes heavily to environmental pollution throughout the textile production chain. As sustainable alternatives, considerable efforts are being made to incorporate biodegradable biopolymers derived from residual biomass, with reasonable production costs, to replace or reduce the use of synthetic petrochemical-based polymers. However, the commercial deployment of these biopolymers is dependent on high biomass availability and a cost-effective supply. Residual forest biomass, with lignocellulosic composition and seasonably available at low cost, constitutes an attractive renewable resource that might be used as raw material. Thus, this review aims at carrying out a comprehensive analysis of the existing literature on the use of residual forest biomass as a source of new biomaterials for the textile industry, identifying current gaps or problems. Three specific biopolymers are considered: lignin that is recovered from forest biomass, and the bacterial biopolymers poly(hydroxyalkanoates) (PHAs) and bacterial cellulose (BC), which can be produced from sugar-rich hydrolysates derived from the polysaccharide fractions of forest biomass. Lignin, PHA, and BC can find use in textile applications, for example, to develop fibers or technical textiles, thus replacing the currently used synthetic materials. This approach will considerably contribute to improving the sustainability of the textile industry by reducing the amount of non-biodegradable materials upon disposal of textiles, reducing their environmental impact. Moreover, the integration of residual forest biomass as renewable raw material to produce advanced biomaterials for the textile industry is consistent with the principles of the circular economy and the bioeconomy and offers potential for the development of innovative materials for this industry. Full article

The transformation of biomass into renewable fuels and chemicals has gained remarkable attention as a sustainable alternative to fossil-based resources. Metal-based catalysts, encompassing transition and noble metals, are crucial in these transformations as they drive critical reactions, such as hydrodeoxygenation, hydrogenation, and reforming. Transition metals, including nickel, cobalt, and iron, provide cost-effective solutions for large-scale processes, while noble metals, such as platinum and palladium, exhibit superior activity and selectivity for specific reactions. Catalytic advancements, including the development of hybrid and bimetallic systems, have further improved the efficiency, stability, and scalability of biomass transformation processes. This review highlights the catalytic upgrading of lignocellulosic, algal, and waste biomass into high-value platform chemicals, biofuels, and biopolymers, with a focus on processes, such as Fischer–Tropsch synthesis, aqueous-phase reforming, and catalytic cracking. Key challenges, including catalyst deactivation, economic feasibility, and environmental sustainability, are examined alongside emerging solutions, like AI-driven catalyst design and lifecycle analysis. By addressing these challenges and leveraging innovative technologies, metal-based catalysis can accelerate the transition to a circular bioeconomy, supporting global efforts to combat climate change and reduce fossil fuel dependence. Full article

Bioresources have been gaining popularity due to their abundance, renewability, and recyclability. Nevertheless, given their diverse composition and complex hierarchical structures, these bio-based sources must be carefully processed to effectively extract valuable raw polymeric materials suitable for producing man-made organic fibres. This review will first highlight the most relevant bio-based sources, with a particular focus on promising unconventional biomass sources (terrestrial vegetables, aquatic vegetables, fungi, and insects), as well as agroforestry and industrial biowaste (food, paper/wood, and textile). For each source, typical applications and the biopolymers usually extracted will also be outlined. Furthermore, acknowledging the challenging lignocellulosic structure and composition of these sources, an overview of conventional and emerging pre-treatments and extraction methods, namely physical, chemical, physicochemical, and biological methodologies, will also be presented. Additionally, this review aims to explore the applications of the compounds obtained in the production of man-made organic fibres (MMOFs). A brief description of their evolution and their distinct properties will be described, as well as the most prominent commercial MMOFs currently available. Ultimately, this review concludes with future perspectives concerning the pursuit of greener and sustainable polymeric sources, as well as effective extraction processes. The potential and main challenges of implementing these sources in the production of alternative man-made organic fibres for diverse applications will also be highlighted. Full article

Understanding the deterioration processes in wooden artefacts is essential for accurately assessing their conservation status and developing effective preservation strategies. Advanced imaging techniques are currently being explored to study the impact of chemical changes on the structural and mechanical properties of wood. Nonlinear optical modalities, including second harmonic generation (SHG) and two-photon excited fluorescence (TPEF), combined with fluorescence lifetime imaging microscopy (FLIM), offer a promising non-destructive diagnostic method for evaluating lignocellulose-based materials. In this study, we employed a nonlinear multimodal approach to examine the effects of artificially induced delignification on samples of Norway spruce (Picea abies) and European beech (Fagus sylvatica) subjected to increasing treatment durations. The integration of SHG/TPEF imaging and multi-component fluorescence lifetime analysis enabled the detection of localized variations in nonlinear signals and τ-phase of key biopolymers within wood cell walls. This methodology provides a powerful tool for early detection of wood deterioration, facilitating proactive conservation efforts of wooden artefacts. Full article