A family of lignin-based polyols (LBPs) has been prepared and characterized using a novel and unprecedented synthetic approach consisting of a cationic ring opening polymerization reaction of oxiranes in the presence of tetrahydrofuran as both the solvent and co-monomer and an organosolv lignin (OL) at atmospheric pressure and room temperature in acidic media. This new route avoids the drawbacks of the current base-catalyzed lignin oxypropylation method used to obtain LBPs, such as the formation of a large amount of side products, the harsh reaction conditions (high temperatures (>150 °C) and pressure) resulting in lignin fragmentation and the generation of phenolic moieties that produce an unpleasant odour limiting the fields of application of LBPs. To demonstrate the versatility of the novel proposed synthetic route, several LBPs were obtained using butylene oxide, propylene oxide, glycidol and epichlorohydrin as oxiranes. The characterization of the obtained LBPs was performed by means of gel permeation chromatography (GPC), thermo-gravimetric analysis (TGA), differential scanning calorimetry (DSC), and attenuated total reflection-Fourier transform infrared (ATR-FTIR), as well as determination of the hydroxyl number. LBPs with a lignin content from 11.3 to 30.1 wt%, and weight average molecular weights from 2730 to 30 258 g mol⁻¹, and hydroxyl values from 53 to 253 mg KOH per g were obtained. Furthermore, the reactivity of these LBPs with diisocyanates was evidenced and a plausible reaction mechanism is proposed. This novel developed method is of potential industrial interest, mainly in the field of the pulp industry, of which the major byproduct is lignin, as well as in the bio-polyol and bio-polymer industries.

Lignin-based polyols (LBPs) with controlled microstructure were obtained by cationic ring opening polymerization (CROP) of oxiranes in an organosolv lignin (OL) tetrahydrofuran (THF) solution. The control on the microstructure and consequently on the properties of the LBPs such as hydroxyl number, average molecular weight, melting, crystallization and decomposition temperatures, are crucial to determine the performance and application of the derived-products. The influence of key parameters, for example, molar ratio between the oxirane and the hydroxyl groups content in OLO, initial OL concentration in THF, temperature, specific flow rate and oxirane nature has been investigated. LBPs with hydroxyl numbers from 35 to 217 mg KOH/g, apparent average M_w between 5517 and 52,900 g/mol and melting temperatures from −8.4 to 18.4 °C were obtained. The CROP procedure allows obtaining of tailor-made LBPs for specific applications in a very simple way, opening the way to introduce LBPs as a solid alternative to substitute currently used fossil-based polyols.

The selective hydrogenation of CO₂ for the production of net-zero fuels and essential chemical building blocks is a promising approach to combat climate change. Key to this endeavor is the development of catalysts with high activity and selectivity for desired hydrocarbon products in the C2–C5 range. The process involves a two-step reaction, starting with the reverse water–gas shift (RWGS) reaction and proceeding to the Fischer–Tropsch reactions under high pressure. Understanding the catalyst features that control the selectivity of these pathways is crucial for product formation, as well as identifying morphological changes in the catalysts during the reaction to optimize their performance. In this study, an innovative method for synthesizing iron–ruthenium bimetallic catalysts is introduced, capitalizing on the synergistic effects of these metals as active phases. This method leverages ionic liquids as solvents, allowing for the precise and uniform distribution of active metal phases. Advanced characterizations and extensive catalytic tests have demonstrated that the use of ionic liquids outperformed traditional colloid-based techniques, resulting in superior selectivity for target hydrocarbons. The success of this inventive approach not only advances the field of CO₂ hydrogenation catalysis, but also represents a significant stride towards sustainable e-fuel production.

Carbon dioxide is ideal for carboxylation reactions as a renewable and sustainable C1 feedstock and has significant recognition owing to its low cost, non-toxicity, and high abundance. To depreciate the environmental concentration of CO₂, which causes the greenhouse gas effect, developing new catalytic protocols for organic synthesis in CO₂ utilization is of great importance. This review focuses on carboxylation reactions using CO₂ as a C1 feedstock to synthesize value-added functionalized carboxylic acids and their corresponding derivatives via catalytically generated allyl metal intermediates, photoredox catalysis, and electrocatalysis with a focus on recent developments and opportunities in catalyst design for carboxylation reactions. In this article, we describe recent developments in the carboxylation of C–H bonds, alkenes, and alkynes using CO₂ as the C1 source for various reactions under different conditions, as well as the potential direction for the further development of CO₂ utilization in organic synthesis.

Current global challenges associated with energy security and climate emergency, caused by the combustion of fossil fuels (e.g., jet fuel and diesel), necessitate the accelerated development and deployment of sustainable fuels derived from renewable biomass-based chemical feedstocks. This study focuses on the production of long-chain (straight and branched) ketones by direct α-alkylation of short chain ketones using both homogenous and solid base catalysts in water. Thus, produced long-chain ketones are fuel precursors and can subsequently be hydrogenated to long-chain alkanes suitable for blending in aviation and liquid transportation fuels. Herein, we report a thorough investigation of the catalytic activity of Pd in combination with, (i) homogenous and solid base additives; (ii) screening of different supports using NaOH as a base additive, and (iii) a comparative study of the Ni and Pd metals supported on layered double oxides (LDOs) in α-alkylation of 2-butanone with 1-propanol as an exemplar process. Among these systems, 5%Pd/BaSO₄ with NaOH as a base showed the best results, giving 94% 2-butanone conversion and 84% selectivity to alkylated ketones. These results demonstrated that both metal and base sites are necessary for the selective conversion of 2-butanone to alkylated ketones. Additionally, amongst the solid base additives, Pd/C with 5% Ba/hydrotalcite showed the best result with 51% 2-butanone conversion and 36% selectivity to the alkylated ketones. Further, the screening of heterogenous acid-base catalysts 2.5%Ni/Ba_1.2Mg₃Al₁ exhibited an adequate catalytic activity (21%) and ketone selectivity (47%).