Bio-polyethylene (BioPE, derived from sugarcane), sugarcane bagasse pulp, and two compatibilizers (fossil and bio-based), were used to manufacture biocomposite filaments for 3D printing. Biocomposite filaments were manufactured and characterized in detail, including measurement of water absorption, mechanical properties, thermal stability and decomposition temperature (thermo-gravimetric analysis (TGA)). Differential scanning calorimetry (DSC) was performed to measure the glass transition temperature (Tg). Scanning electron microscopy (SEM) was applied to assess the fracture area of the filaments after mechanical testing. Increases of up to 10% in water absorption were measured for the samples with 40 wt% fibers and the fossil compatibilizer. The mechanical properties were improved by increasing the fraction of bagasse fibers from 0% to 20% and 40%. The suitability of the biocomposite filaments was tested for 3D printing, and some shapes were printed as demonstrators. Importantly, in a cradle-to-gate life cycle analysis of the biocomposites, we demonstrated that replacing fossil compatibilizer with a bio-based compatibilizer contributes to a reduction in CO₂-eq emissions, and an increase in CO₂ capture, achieving a CO₂-eq storage of 2.12 kg CO₂ eq/kg for the biocomposite containing 40% bagasse fibers and 6% bio-based compatibilizer.

Soda-ethanol pulps, prepared from a forestry residue pine sawdust, were treated according to high-consistency enzymatic fibrillation technology to manufacture nanocellulose. The obtained nanocellulose was characterized and used as ink for three-dimensional (3D) printing of various structures. It was also tested for its moisture sorption capacity and cytotoxicity, as preliminary tests for evaluating its suitability for wound dressing and similar applications. During the high-consistency enzymatic treatment it was found that only the treatment of the O₂-delignified pine pulp resulted in fibrillation into nano-scale. For 3D printing trials, the material needed to be fluidized further. By 3D printing, it was possible to fabricate various structures from the high-consistency enzymatic nanocellulose. However, the water sorption capacity of the structures was lower than previously seen with porous nanocellulose structures, indicating that further optimization of the material is needed. The material was found not to be cytotoxic, thus showing potential as material, e.g., for wound dressings and for printing tissue models.

New biobased processes and products are emerging to replace conventional ones in the search for sustainable development. Xylitol is one of the most commercially valuable products from xylan-rich lignocellulosic biomass. Xylitol has multiple applications in the pharmaceutical, food, nutraceutical, and beverage industries. Recent research focuses on obtaining xylose from low-cost lignocellulosic materials through the biological route, optimizing xylitol conversion, improving byproduct removal, and increasing crystallization speed. The biological route can be an environmentally friendly alternative due to the possibility of lower energy demand and utilizing renewable feedstocks which are key factors to reach sustainability. Several integration strategies are being evaluated and are critical to developing a commercial platform. Process integration can considerably reduce the demand for energy and reagents. Also, the value-added products produced alongside xylitol are crucial, and these products are usually energy generation and bioethanol. Further, new value-added products show promising results and are relevant to improving the economic performance of the processes. The market trends of xylitol are expected to reach close to USD 1.5 billion in 2030. In addition, the improvement needed in the conversion steps and obtained yields, producing commercial-scale xylitol through the biological route, is a promising alternative to finding a more sustainable way to produce xylitol.

Alkaline treatment is well suited for extracting high-molecular-weight hemicelluloses, specifically hardwoods xylans, which, due to their polymer structure and chemical characteristics, enable the production of films with desirable mechanical, barrier, and optical properties for packaging applications. Despite its relevance, the optimization of antisolvent addition has received little attention in the literature. This study explores the use of eucalyptus industrial residue as feedstock, utilizing a statistical design to determine the optimal extraction conditions for hemicelluloses while minimizing the lignin content in the recovered liquor. The process uses alkali loads that are compatible with those in conventional Kraft pulp mills. Optimal extraction conditions involve a temperature of 105 °C, 16.7% NaOH charge, and 45 min at maximum temperature. The resulting liquor was subjected to ethanol precipitation under varying pH conditions (initial pH, 9, 7, 5, and 2) and different ethanol-to-liquor ratios (1:1 to 4:1). The acidification was performed using hydrochloric, sulfuric, and acetic acids. Ethanol served as the main antisolvent, while isopropyl alcohol and dioxane were tested for comparison. Results show that 2.3 ± 0.2% of xylans (based on oven-dry biomass) could be extracted, minimizing lignin content in the liquor. This value corresponds to the extraction of 15.6% of the xylans present in the raw material. The highest xylan precipitation yield (78%) was obtained at pH 7, using hydrochloric acid for pH adjustment and an ethanol-to-liquor ratio of 1:1. These findings provide valuable insight into optimizing hemicellulose recovery through antisolvent precipitation, contributing to more efficient biomass valorization strategies within lignocellulosic biorefineries.

We identified the significant technical-economic factors, uncertainty, and risks in the pine sawdust biorefinery design for bioethylene and lignin production.

The soda–ethanol process was conceived as a sulfur-free pulping process, which may also be an alternative to conventional alkaline pulping, such as kraft or soda–AQ in the biorefinery context. An in-depth study using two experimental designs was conducted to establish the viability of soda–ethanol delignification of pine sawdust. At first, a simple factorial design involving the ethanol–water ratio (ethanol:water) and the alkaline load (AL, % over dry wood, odw) was applied to define the levels of these variables and their eventual interaction. Then, a 3² experimental design was performed to evaluate the ability of the process concerning the pulping of pine sawdust. The tested conditions were carefully selected to screen a broad range of cooking times (60, 100, and 140 min) and alkaline loads (19.0, 23.3, and 27.6 %odw) to obtain pulps with different extents of delignification (residual lignin contents). Finally, the kraft, soda–AQ, and soda–ethanol treatments were compared. Soda–ethanol pulping was shown to be a suitable delignification stage for a biorefinery scheme of Pinus elliottii and Pinus taeda sawdust. It has many advantages over traditional processes regarding its environmental impact, harmless chemicals, and selectivity. The tested conditions were similar to those frequently used in conventional pulping at an industrial scale, suggesting the technical feasibility of the soda–ethanol process for pine sawdust processing.