Future materials should be made from renewable resources and be sustainable without compromising the mechanical properties compared to conventional products. Kraft lignin is an available renewable raw material, sourced globally as a by-product from paper pulp production, and currently burnt at a low value. Kraft lignin has been converted into thermoplastics, however the mechanical properties worsen by degree of blending. Thermosets containing kraft lignin give materials with high strength, where the lignin matrix contributes to the mechanical properties. However, pre-fractionation or multistep chemistries have been applied to give high performance materials. Herein, we have combined kraft lignin with bio-based glycerol 1,3-diglycidyl ether to give a resin with enhanced mechanical properties. This resin – LigniSet® – is odorless, which is a unique property for kraft lignin-based products. The resin is, due to its hydrophilicity, compatible with natural fibers to give strong composite materials. The material can be recycled to give new materials without reduction in performance. Life cycle assessment shows that transformation of lignin to materials instead of burning shows significant benefits with respect to environmental sustainability.

Deoxygenation of epoxides to alkenes is a valuable transformation in organic synthesis that enables the formation of carbon–carbon double bonds (alkenes or olefins) from epoxides. This reaction offers an alternative strategy for the interconversion of alkene stereoisomers via epoxide formation and stereoinvertive deoxygenation. This review summarizes advancements in epoxide deoxygenation from 2010 to the present, organized by catalytic platforms, including homogeneous transition-metal catalysis, heterogeneous transition-metal catalysis, transition-metal-free protocols, photochemical and electrochemical approaches, and biocatalytic transformations. Mechanistic insights are emphasized, including the role of reductants and catalysts as well as stereochemical outcomes. A brief outlook is presented on the challenges and opportunities for advancing sustainable, stereospecific epoxide deoxygenation.

In this study, cellulose-based films were developed by using microfibrillated cellulose (MFC) and lignin-containing microfibrillated cellulose (Lig-MFC) derived from sequentially extracted spruce bark. The films were coated with the hydrophilic extractives from the fractionation, resulting in additional MFC-coated and Lig-MFC-coated cellulose films. A combination of morphological (AFM), surface (water contact angle (WCA), roughness), optical (UV–vis), and mechanical properties was analyzed to assess structure–property relationships. Coated films exhibited significantly enhanced hydrophobicity and UV-shielding, with WCA increasing from 47° to 76° for MFC and from 66° to 71° for Lig-MFC. Notably, MFC-coated films displayed superior mechanical performance, with a tensile strength of 119 MPa and elongation of 11%, surpassing most lignocellulosic-based films in the literature derived from bark. In addition, this tensile strength falls within or above the range of commonly used materials, such as kraft liner, PET, and LDPE, suggesting realistic opportunities for substitution in short-lived packaging applications. AFM analysis revealed a reduction in surface roughness after coating, correlating with an enhanced WCA. Compared with similar biobased films in the literature, the extractive-coated MFC films show superior performance in terms of strength, flexibility, and UV-shielding properties. This valorization route offers both economic and environmental sustainability advantages compared with incineration for energy recovery. A comparative life cycle assessment (LCA) study showed that valorization of the pulp and hydrophilic extractives from the bark biorefinery into different qualities of MFCs gave substantial climate change benefits stemming from the possibility of substituting packaging materials with high inherent environmental impact.

ZrO₂ incorporated onto Beta zeolite demonstrated high reactivity and selectivity in converting biomass-derived xylose to ethyl levulinate (EL) without the need for external hydrogen. The active sites in ZrO₂, in conjunction with the confinement control provided by the BEA structure, enhance the rate of dehydration, transfer hydrogenation, and ethanolysis, effectively converting xylose via furfural (FF) and furfuryl alcohol (FA) to EL. The highest yields of EL were achieved at 40.3, 21.5 and 52.9% from xylose, xylan and empty fruit bunch (EFB), respectively. Characterization of ZrO₂ dispersed on Beta zeolite indicates its critical role in the catalytic transfer hydrogenation step. Proper tuning of Brønsted and Lewis acid sites efficiently drives the conversion of biomass-derived xylose to EL. Additionally, the Zr-Beta catalysts can be reused up to three times with minimal decline in EL production and the catalyst can be regenerated to achieve more than 90% of its initial activity in both xylose and EFB reactions.

A highly efficient and cost-effective Ni-Mo/Zr-SBA-15 catalyst was developed for the selective hydrogenation of biomass-derived oleic acid to octadecanol, a high-value fatty alcohol. By systematically optimizing the Ni/Mo weight ratio and varying the ZrO_x content, the 10Ni-10Mo/10Zr-SBA-15 catalyst exhibited excellent performance, achieving 100% conversion and 93.5% selectivity to octadecanol at 220 °C and 3.0 MPa of H₂. Characterization results revealed that Mo species enhanced Ni dispersion, while the synergistic Ni-MoO_x interfacial sites contributed to the high catalytic performance. Metallic Ni is the main active site for H₂ activation/dissociation. The incorporation of Mo species in the 10Ni/10Zr-SBA-15 catalyst increased the density of oxygen vacancies and enhanced the amount of Lewis acid sites. Additionally, ZrO_x species contributed to the properties of the SBA-15 support, introducing more Lewis acid sites to the catalyst. The combined effect of metallic sites, oxygen vacancy/redox centers, and Lewis acidity facilitated the hydrogenation process, C–O/C = O bond activation, and strengthened oleic acid adsorption, which was crucial for octadecanol production. Moreover, the 10Ni-10Mo/10Zr-SBA-15 catalyst demonstrated high stability and reusability, maintaining its activity over four consecutive reaction cycles without significant deactivation.

An indolizidine alkaloid, (−)-8a-epi-lentiginosine was synthesized from d-glucose using the Pd-BiPhePhos catalyzed intramolecular Tsuji–Trost reaction of non−derivatized allylic alcohol as a key construction of the hydroxylated pyrrolidine ring to give the desired product in good yield and high stereospecificity (dr = 97:3). The absolute configuration and structure of (−)-8a-epi-lentiginosine were confirmed by NMR and X-ray crystal structure analysis. The crystal structure of (−)-8a-epi-lentiginosne showed the envelope conformation of the five-membered ring, which is an N-atom in the endo-position, and the fused six-membered ring adopts a chair conformation similar to the DFT optimized structure. The solid-state packing is dominated by a 1D-hydrogen-bonded network along the a-axis involving both hydroxyl groups and the amine. The large HOMO–LUMO energy gap indicated the high stability of the compound.

Bark represents 10 % dry weight of spruce trees and is a major side stream from pulp production. Currently, pulp mills burn bark to produce energy with a low economic value, directly emitting biogenic carbon dioxide to the atmosphere. Biorefining bark using a continuous flow-through fractionation process generates high added-value compounds (tall oil, starch, phenol, and pulp) that allow for extended carbon storage durations. This study assesses the potential future environmental impacts of valorising bark instead of burning it. We conduct a LCA study combining a prospective consequential modelling perspective with an input-related functional unit and account for the effects of storing biogenic carbon in the bark-based products. Our findings show that biorefining bark maintains lower environmental impacts than combustion, reducing time-differentiated climate impacts by up to 30 %, but only when the carbon dioxide used for pulping is recirculated and the fractionation processes are integrated with a co-located pulp mill supplying surplus waste energy, considered to have no associated environmental impacts. Storing biogenic carbon for a longer period of time has a positive effect on mitigating short-term climate impacts. However, our analysis reveals that while time-dependent climate impacts decrease, there is an increase in human toxicity and ecotoxicity impacts, with combustion performing better in these categories. This highlights the importance of expanding the scope of LCA studies to include impacts beyond climate change. Overall, this work demonstrates that combining a prospective consequential modelling perspective with an input-related functional unit is a relevant approach to study potential future impacts of emerging biorefineries and thus supports the development of a sustainable circular bioeconomy.

α-Amino ketones were synthesized by a Meinwald rearrangement of biomass-based amino epoxides using copper(II) triflate as a catalyst. The regioselectivity of the rearrangement can be rationalized in terms of the reaction proceeding via the most stable carbocationic intermediate to give various α-amino α′-aryl ketones in moderate to good yields. This is an attractive method to prepare α-amino ketones using a benign and inexpensive catalyst.

A novel combination of strong Brønsted acidity (B), from propyl sulfonic acid functionalized on H–Y zeolite (HY-PrSO3H); Lewis acidity (L), by dispersion of SnO2; and confinement control showed high reactivity and selectivity in the conversion of cellulose to ethyl levulinate (EL). An optimal catalyst for EL formation was found by combining the Faujasite (FAU) structure, which incorporates strong Brønsted and Lewis acids in a B/L acidity ratio of 3.9. The resulting catalyst showed high yield of EL 63.7, 57.6 and 24.8%, from fructose, glucose, and empty palm fruit bunch (EFB), respectively. By isolating the cellulose from EFB, the yield from cellulose in EFB could be increased to 42.8% with a selectivity of 74.8%. Moreover, the catalyst could be reused up to 3 times with decreased of EL formation; and moreover, 90% of initial activity was regained after regeneration.