Catalytic Production of Levulinic Acid (LA) from Actual Biomass

Optimisation of the biological production of levulinic acid in a mixed microbial culture fed with synthetic grape pomace

Levulinic acid (LA) is a polymer with a vast industrial application range and can be co-produced as a minor by-product during the biological production of polyhydroxyalkanoates (PHA). However, the influence of key parameters as tools for favouring the production of LA over PHA is still unclear. In this study, we investigated how several critical operational conditions, i.e., carbon-nitrogen ratio (C/N), organic loading rate (OLR) and airflow, can be optimised to favour LA accumulation over PHA production by a mixed microbial culture (MMC), using synthetic grape pomace (GP) hydrolysate as the substrate. The results showed that it was possible to direct the MMC towards LA accumulation instead of PHA. The maximum LA yield was 2.7 ± 0.2 g LA/(L·d) using a C/N of 35, an airflow of 5 L/min and an OLR of 4 g sCOD/(L·d). The OLR and, to a lesser extent, the C/N ratio were the main factors significantly and positively correlated with the biological synthesis of LA.

Chitosan as a Bio-Based Ligand for the Production of Hydrogenation Catalysts

Bio-based polymers are attracting increasing interest as alternatives to harmful and environmentally concerning non-biodegradable fossil-based products. In particular, bio-based polymers may be employed as ligands for the preparation of metal nanoparticles (M(0)NPs). In this study, chitosan (CS) was used for the stabilization of Ru(0) and Rh(0) metal nanoparticles (MNPs), prepared by simply mixing RhCl3 × 3H2O or RuCl3 with an aqueous solution of CS, followed by NaBH4 reduction. The formation of M(0)NPs-CS was confirmed by Fourier Transform Infrared Spectroscopy (FT-IR), Differential Scanning Calorimetry (DSC), Thermal Gravimetric Analysis (TGA), Scanning Electron Microscopy (SEM), Energy-Dispersive X-ray Analysis (EDX), Transmission Electron Microscopy (TEM) and X-ray Diffraction (XRD). Their size was estimated to be below 40 nm for Rh(0)-CS and 10nm for Ru(0)-CS by SEM analysis. M(0)NPs-CS were employed for the hydrogenation of (E)-cinnamic aldehyde and levulinic acid. Easy recovery by liquid-liquid extraction made it possible to separate the catalyst from the reaction products. Recycling experiments demonstrated that M(0)NPs-CS were highly efficient up to four times in the best hydrogenation conditions. The data found in this study show that CS is an excellent ligand for the stabilization of Rh(0) and Ru(0) nanoparticles, allowing the production of some of the most efficient, selective and recyclable hydrogenation catalysts known in the literature.

Catalytic Conversion of Levulinic Acid into 2-Methyltetrahydrofuran: A Review

Biomass-derived furanics play a pivotal role in chemical industries, with 2-methyltetrahydrofuran (2-MTHF), a hydrogenated product of levulinic acid (LA), being particularly significant. 2-MTHF finds valuable applications in the fuel, polymer, and chemical sectors, serving as a key component in P-series biofuel and acknowledged as a renewable solvent for various chemical processes. Numerous research groups have explored catalytic systems to efficiently and selectively convert LA to 2-MTHF, using diverse metal-supported catalysts in different solvents under batch or continuous process conditions. This comprehensive review delves into the impact of metal-supported catalysts, encompassing co-metals and co-catalysts, on the synthesis of 2-MTHF from LA. The article also elucidates the influence of different reaction parameters, such as temperature, type and quantity of hydrogen source, and time. Furthermore, the review provides insights into reaction mechanisms for all documented catalytic systems.

Microwave-assisted deep eutectic solvents/dimethyl sulfoxide system for efficient valorization of sugar bagasse waste into platform chemicals: A biorefinery approach for circular bioeconomy

The exploitation of lignocellulosic biomass (LB) such as sugar bagasse waste in biorefineries is the most cost-effective and favourable sustainable approach to producing essential platform chemicals, materials, and energy environmentally benignly. Herein, a microwave-mediated deep eutectic solvents (DESs)/dimethyl sulfoxide (DMSO) system for efficiently processing LB waste into platform chemicals was proposed thereof. Under optimized appropriate diverse parameters such as solvent varieties, catalyst dosage, DMSO addition, reaction time and temperature, the proposed catalytic system (i.e., microwave mediated DESs/DMSO system) has demonstrated significant yields of 5-hydroxymethylfurfural (5-HMF), furfural (FF) and levulinic acid (LevA) of 31.29 %, 28.38 % and 35.65 %, respectively. These favourable results were obtained at the reaction temperature of 140 °C for 40 min. The anticipated catalytic system's activation energy (Ea) was found to be 29.11 kJ/mol. Hence, a practical, inexpensive and sustainable process with the potential of high-value platform chemicals, explicitly for a sustainable strategy in a circular bioeconomy was proposed.

Experimental and Kinetic Modeling of Galactose Valorization to Levulinic Acid

Levulinic acid, a versatile chemical building block, was derived from C6-sugar galactose using sulfuric acid as the catalyst. Galactose is monosaccharide of polysaccharides constituent that is mostly contained in third generation biomass, macro-microalgae. It currently receives high attention to be a source of renewable feedstock. The effect of temperature, catalyst concentration and initial substrate loadings were studied for 60 min, in the temperature range of 150–190 °C, acid concentration of 0.25–0.75 M and initial substrate loading of 0.05–0.25 M. The highest levulinic acid yield of 40.08 wt% was achieved under the following conditions: 0.05 M galactose, 0.75 M acid concentration, 170 °C temperature, and 40 min reaction time. The kinetic model was developed by first order pseudo-irreversible reaction. The results showed that the proposed model could capture the experimental data well. These results suggested that galactose, derived from macro- and micro-algae, can potentially be converted and applied for platform chemicals. Copyright © 2022 by Authors, Published by BCREC Group. This is an open access article under the CC BY-SA License (https://creativecommons.org/licenses/by-sa/4.0). 

Physico-Chemical Properties and Principal Component Analysis of Biobased Thermosets Developed with Different Batches of Industrial Humins

Humins have already shown their potential as thermosetting resins to produce crosslinked networks and composites, with a large variety of properties depending on the used macromolecular approach. Our group has shown that a very interesting class of materials with tunable flexibility can be made by humins co-polymerization with glycerol diglycidyl ether (GDE). To create a clearer picture on structure-reactivity-properties-application interdependent relationship, a principal component analysis (PCA) was applied on several humins batches. The PCA allowed to obtain a clear discrimination between the humins/GDE resins samples in 3 groups which correlate very well with the results of copolymerization reactivity (DSC) and thermosets properties: crosslink density, thermal stability, tan δ, Shore D hardness values, etc.

Kinetic Study of Levulinic Acid from Spirulina platensis Residue

Microalgae have the potential to emerge as renewable feedstocks to replace fossil resources in producing biofuels and chemicals. Levulinic acid is one of the most promising substances which may serve as chemical building blocks. This work investigated the use of Spirulina platensis residue (solid residue after lipids extraction) to produce LA via acid hydrolysis reaction. In this study, Spirulina platensis residue was set to have a solid-liquid ratio of 5% (w/v). The effect of process parameters on the Spirulina platensis residue to levulinic acid hydrolysis reaction was observed at temperatures ranging from 140 to 180 °C under four acid concentrations, i.e., 0.25, 0.5, 0.8, and 1 M. A simplified kinetic model was also developed to describe the behavior of Spirulina platensis residue conversion to levulinic acid, based on the pseudo-homogeneous-irreversible-1^st order reaction. The results showed that the proposed model could capture the experimental data well. The reaction network also considered involvement of intermediate products namely glucose and 5-hydroxymethylfurfural. The results showed that Spirulina platensis residue, with acid catalysts, can be used to produce levulinic acid, and the kinetic model can provide useful information for understanding the Spirulina platensis residue to levulinic acid hydrolysis reaction.

2-Year-Old and 3-Year-Old Italian ALS Patients with Novel ALS2 Mutations: Identification of Key Metabolites in Their Serum and Plasma

Pathogenic variants in ALS2 have been detected mostly in juvenile cases of amyotrophic lateral sclerosis (ALS), affecting mainly children and teenagers. Patients with ALS2 mutations demonstrate early onset cortical involvement in ALS. Currently, there are no effective treatment options. There is an immense need to reveal the underlying causes of the disease and to identify potential biomarkers. To shed light onto the metabolomic events that are perturbed with respect to ALS2 mutations, we investigated the metabolites present in the serum and plasma of a three-year-old female patient (AO) harboring pathogenic variants in ALS2, together with her relatives, healthy male and female controls, as well as another two-year-old patient DH, who had mutations at different locations and domains of ALS2. Serum and plasma samples were analyzed with a quantitative metabolomic approach to reveal the identity of metabolites present in serum and plasma. This study not only shed light onto the perturbed cellular pathways, but also began to reveal the presence of a distinct set of key metabolites that are selectively present or absent with respect to ALS2 mutations, laying the foundation for utilizing metabolites as potential biomarkers for a subset of ALS.

Catalytic Production of Levulinic and Formic Acids from Fructose over Superacid ZrO2–SiO2–SnO2 Catalyst

Catalytic conversion of fructose to levulinic and formic acids over tin-containing superacid (H0 = −14.52) mixed oxide was studied. Mesoporous ZrO2–SiO2–SnO2 (Zr:Si:Sn = 1:2:0.4) was synthesized by the sol–gel method. The fructose transformation was carried out in a rotated autoclave at 160–190 °C for 1–5 h using a 20 wt.% aqueous solution. The results showed that doping ZrO2–SiO2 samples with Sn4+ ions improved both fructose conversion and selectivity toward levulinic and formic acids. Under optimal conditions of 180 °C, 3.5 h and fructose to catalyst weight ratio 20:1, levulinic and formic acids yields were 80% and 90%, respectively, at complete fructose conversion. At this, humic substances formed in the quantity of 10 wt.% based on the target products.

Reaction Kinetics of Levulinic Acid Synthesis from Glucose Using Bronsted Acid Catalyst

Glucose is one of the primary derivative products from lignocellulosic biomass, which is abundantly available. Glucose has excellent potential to be converted into valuable compounds such as ethanol, sorbitol, gluconic acid, and levulinic acid (LA). Levulinic acid is an exceptionally promising green platform chemical. It comprises two functional groups, ketone and carboxylate, acting as highly reactive electrophiles for a nucleophilic attack. Therefore, it has extensive applications, including fuel additives, raw materials for the pharmaceutical industry, and cosmetics. This study reports the reaction kinetics of LA synthesis from glucose catalyzed by hydrochloric acid (HCl), a Bronsted acid, that was carried out under a wide range of operating conditions; i.e. the temperature of 140–180 °C, catalyst concentration of 0.5–1.5 M, and initial glucose concentration of 0.1–0.5 M. The highest LA yield of 48.34 % was able to be obtained from an initial glucose concentration of 0.1 M and by using 1 M HCl at 180 °C. The experimental results show that the Bronsted acid-catalyzed reaction pathway consists of glucose decomposition to levoglucosan (LG), conversion of LG to 5-hydroxymethylfurfural (HMF), and rehydration of HMF to LA. The experimental data yields a good fitting by assuming a first-order reaction model. Copyright © 2021 by Authors, Published by BCREC Group. This is an open access article under the CC BY-SA License (https://creativecommons.org/licenses/by-sa/4.0). 

Valorization of cigarette butts for synthesis of levulinic acid as top value-added chemicals

Unprecedented in the literature, levulinic acid (LA), one of the top value-added intermediates of chemical industry, is obtained from cigarette butts as cellulose feedstock by means of a one-pot hydrothermal process carried out at 200 °C for 2 h and catalysed by phosphoric acid. The protocol avoids the use of more aggressive and toxic H₂SO₄ and HCl, that are generally employed on several cellulose sources (e.g. sludge paper), thus minimizing corrosion phenomena of plants. Neither chemical pre-treatment of butts nor specific purification procedure of LA are required. Notably, by simply modifying acid catalyst (e.g. using CH₃COOH), another top value-added fine chemical such as 5-hydroxymethylfuraldehyde (HMF) is obtained, thus widening the scope of the method. Being cigarette filters a waste available in quantities of megatonnes per year, they represent an unlimited at no cost source of cellulose, thus enabling the up-scale to an industrial level of LA production.

Mini-Review on the Synthesis of Furfural and Levulinic Acid from Lignocellulosic Biomass

Efficient conversion of renewable biomass into value-added chemicals and biofuels is regarded as an alternative route to reduce our high dependence on fossil resources and the associated environmental issues. In this context, biomass-based furfural and levulinic acid (LA) platform chemicals are frequently utilized to synthesize various valuable chemicals and biofuels. In this review, the reaction mechanism and catalytic system developed for the generation of furfural and levulinic acid are summarized and compared. Special efforts are focused on the different catalytic systems for the synthesis of furfural and levulinic acid. The corresponding challenges and outlooks are also observed.

Synergistic Catalytic Effect of Sulphated Zirconia—HCl System for Levulinic Acid and Solid Residue Production Using Microwave Irradiation

The synergistic conversion of Miscanthus xGiganteous with sulphated zirconia and dilute hydrochloric acid was investigated. The sulphated zirconia was prepared using H2SO4 impregnation and characterised using X-ray Diffraction (XRD), Energy-dispersive X-ray (EDX), Scanning Electron Miscroscope (SEM) spectroscopy and nitrogen adsorption–desorption measurements. The microwave-assisted reaction was evaluated at various temperatures, reaction times and catalyst-to-biomass ratios, with and without the presence of trace HCl in the solution medium for the conversion of Miscanthus xGiganteous to levulinic acid. The highest levulinic acid yield of 63.8% was achieved at 160 °C, 80 min and a 2:1 catalyst-to-biomass ratio, with 10 mM HCl. The catalyst recyclability was investigated with and without calcination, finding that significant humin deposition on the catalyst surface likely caused catalyst deactivation. The post-reaction solid residue was also characterised using SEM, EDX, XRD, elemental composition and nitrogen adsorption–desorption measurements. Findings indicate that this residue could potentially be used as a soil amendment or as a fuel source. The synergistic conversion of real lignocellulosic biomass with sulphated zirconia and trace hydrochloric acid showed remarkable promise and should be investigated further.

Novel Intensified Alternatives for Purification of Levulinic Acid Recovered from Lignocellulosic Biomass

The development of a bio-based economy has its foundations in the development of efficient processes to optimize biomass potential. In this context there are a multitude of molecules that can be either synthetized or recovered from biomass, among those the so-called 12 building-blocks reported by the US Department of Energy. Even if their identification and importance is clearly defined, research efforts concerning the purification or separation of these platform molecules are limited. To fill this gap, different configurations for the purification of levulinic acid recovered from lignocellulosic biomass are examined and compared in this work. In particular, hybrid configurations obtained by the combination of liquid-liquid extraction and distillation have been considered. It was demonstrated how a deep understanding of the subspace including all extraction-assisted simple column distillation configurations represents a fundamental step in the synthesis of different process alternatives. From a separation efficiency and economic standpoint, the proposed intensified liquid-liquid thermally equivalent configuration (LL-TE) and liquid-liquid side stream column configuration (LL-SSC) are promising solutions. Nonetheless, their performances are deeply interrelated to the purity target defined by the designer.

Metabolic engineering of Saccharomyces cerevisiae for the production of top value chemicals from biorefinery carbohydrates

The implementation of biorefineries for a cost-effective and sustainable production of energy and chemicals from renewable carbon sources plays a fundamental role in the transition to a circular economy. The US Department of Energy identified a group of key target compounds that can be produced from biorefinery carbohydrates. In 2010, this list was revised and included organic acids (lactic, succinic, levulinic and 3-hydroxypropionic acids), sugar alcohols (xylitol and sorbitol), furans and derivatives (hydroxymethylfurfural, furfural and furandicarboxylic acid), biohydrocarbons (isoprene), and glycerol and its derivatives. The use of substrates like lignocellulosic biomass that impose harsh culture conditions drives the quest for the selection of suitable robust microorganisms. The yeast Saccharomyces cerevisiae, widely utilized in industrial processes, has been extensively engineered to produce high-value chemicals. For its robustness, ease of handling, genetic toolbox and fitness in an industrial context, S. cerevisiae is an ideal platform for the founding of sustainable bioprocesses. Taking these into account, this review focuses on metabolic engineering strategies that have been applied to S. cerevisiae for converting renewable resources into the previously identified chemical targets. The heterogeneity of each chemical and its manufacturing process leads to inevitable differences between the development stages of each process. Currently, 8 of 11 of these top value chemicals have been already reported to be produced by recombinant S. cerevisiae. While some of them are still in an early proof-of-concept stage, others, like xylitol or lactic acid, are already being produced from lignocellulosic biomass. Furthermore, the constant advances in genome-editing tools, e.g. CRISPR/Cas9, coupled with the application of innovative process concepts such as consolidated bioprocessing, will contribute for the establishment of S. cerevisiae-based biorefineries.

Direct Alcoholysis of Carbohydrate Precursors and Real Cellulosic Biomasses to Alkyl Levulinates: A Critical Review

Alkyl levulinates (ALs) represent outstanding bio-fuels and strategic bio-products within the context of the marketing of levulinic acid derivatives. However, their synthesis by acid-catalyzed esterification of pure levulinic acid, or by acid-catalyzed alcoholysis of furfuryl alcohol, although relatively simple, is still economically disadvantageous, due to the high costs of the pure precursors. The direct one-pot alcoholysis of model C6 carbohydrates and raw biomass represents an alternative approach for the one-step synthesis of ALs. In order to promote the market for these bio-products and, concurrently, the immediate development of new applications, it is necessary to speed up the intensification of their production processes, and this important achievement is onlypossible by using low-cost or, even better, waste biomasses, as starting feedstocks. This review provides an overview of the most recent and promising advances on the one-pot production of ALs from model C6 carbohydrates and real biomasses, in the presence of homogeneous or heterogeneous acid catalysts. The use of model C6 carbohydrates allows for the identification of the best obtainable ALs yields, resulting in being strategic for the development of new smart catalysts, whose chemical properties must be properly tuned, taking into account the involved reaction mechanism. On the other hand, the transition to the real biomass now represents a necessary choice for allowing the next ALs production on a larger scale. The improvement of the available synthetic strategies, the use of raw materials and the development of new applications for ALs will contribute to develop more intensified, greener, and sustainable processes.

Production of Levulinic Acid from Cellulose and Cellulosic Biomass in Different Catalytic Systems

The reasonable and effective use of lignocellulosic biomass is an important way to solve the current energy crisis. Cellulose is abundant in nature and can be hydrolyzed to a variety of important energy substances and platform compounds—for instance, glucose, 5-hydroxymethylfurfural (HMF), levulinic acid (LA), etc. As a chemical linker between biomass and petroleum processing, LA has become an ideal feedstock for the formation of liquid fuels. At present, some problems such as low yield, high equipment requirements, difficult separation, and serious environmental pollution in the production of LA from cellulose have still not been solved. Thus, a more efficient and green catalytic system of this process for industrial production is highly desired. Herein, we focus on the reaction mechanism, pretreatment, and catalytic systems of LA from cellulose and cellulosic biomass, and a series of existing technologies for producing LA are reviewed. On the other hand, the industrial production of LA is discussed in depth to improve the yield of LA and make the process economical and energy efficient. Additionally, practical suggestions for the enhancement of the stability and efficiency of the catalysts are also proposed. The use of cellulose to produce LA is consistent with the concept of sustainable development, and the dependence on fossil resources will be greatly reduced through the realization of this process route.

New Intensification Strategies for the Direct Conversion of Real Biomass into Platform and Fine Chemicals: What Are the Main Improvable Key Aspects?

Nowadays, the solvothermal conversion of biomass has reached a good level of development, and now it is necessary to improve the process intensification, in order to boost its further growth on the industrial scale. Otherwise, most of these processes would be limited to the pilot scale or, even worse, to exclusive academic investigations, intended as isolated applications for the development of new catalysts. For this purpose, it is necessary to improve the work-up technologies, combining, where possible, reaction/purification unit operations, and enhancing the feedstock/liquid ratio, thus improving the final concentration of the target product and reducing the work-up costs. Furthermore, it becomes decisive to reconsider more critically the choice of biomass, solvent(s), and catalysts, pursuing the biomass fractionation in its components and promoting one-pot cascade conversion routes. Screening and process optimization activities on a laboratory scale must be fast and functional to the flexibility of these processes, exploiting efficient reaction systems such as microwaves and/or ultrasounds, and using multivariate analysis for an integrated evaluation of the data. These upstream choices, which are mainly of the chemist’s responsibility, are fundamental and deeply interconnected with downstream engineering, economic, and legislative aspects, which are decisive for the real development of the process. In this Editorial, all these key issues will be discussed, in particular those aimed at the intensification of solvothermal processes, taking into account some real case studies, already developed on the industrial scale.

Microbial and enzymatic conversion of levulinic acid, an alternative building block to fermentable sugars from cellulosic biomass

Levulinic acid (LA) is an important chemical building block listed among the top 12 value-added chemicals by the United States Department of Energy, and can be obtained through the hydrolysis of lignocellulosic biomass. Using the same approach as in the catalytic production of LA from biomass, catalytic methods to upgrade LA to higher value chemicals have been investigated. Since the discovery of the catabolic genes and enzymes in the LA metabolic pathway, bioconversion of LA into useful chemicals has attracted attention, and can potentially broaden the range of biochemical products derived from cellulosic biomass. With a brief introduction to the LA catabolic pathway in Pseudomonas spp., this review summarizes the current studies on the microbial conversion of LA into bioproducts, including the recent developments to achieve higher yields through genetic engineering of Escherichia coli cells. Three different types of reactions during the enzymatic conversion of LA are also discussed. KEY POINTS: • Levulinic acid is an alternative building block to sugars from cellulosic biomass. • Introduction of levulinic acid bioconversion with natural and engineered microbes. • Initial enzymatic conversion of levulinic acid proceeds via three different pathways. • 4-Hydroxyvalerate is one of the target chemicals for levulinic acid bioconversion.

MCM-41 Supported Co-Based Bimetallic Catalysts for Aqueous Phase Transformation of Glucose to Biochemicals

The transformation of glucose into valuable biochemicals was carried out on different MCM-41-supported metallic and bimetallic (Co, Co-Fe, Co-Mn, Co-Mo) catalysts and under different reaction conditions (150 °C, 3 h; 200 °C, 0.5 h; 250 °C, 0.5 h). All catalysts were characterized using N2 physisorption, Temperature Programmed Reduction (TPR), Raman, X-ray Diffraction (XRD) and Temperature Programmed Desorption (TPD) techniques. According to the N2-physisorption results, a high surface area and mesoporous structure of the support were appropriate for metal dispersion, reactant diffusion and the formation of bioproducts. Reaction conditions, bimetals synergetic effects and the amount and strength of catalyst acid sites were the key factors affecting the catalytic activity and biochemical selectivity. Sever reaction conditions including high temperature and high catalyst acidity led to the formation mainly of solid humins. The NH3-TPD results demonstrated the alteration of acidity in different bimetallic catalysts. The 10Fe10CoSiO2 catalyst (MCM-41 supported 10 wt.%Fe, 10 wt.%Co) possessing weak acid sites displayed the best catalytic activity with the highest carbon balance and desired product selectivity in mild reaction condition. Valuable biochemicals such as fructose, levulinic acid, ethanol and hydroxyacetone were formed over this catalyst.

Continuous Flow Upgrading of Selected C2-C6 Platform Chemicals Derived from Biomass

The ever increasing industrial production of commodity and specialty chemicals inexorably depletes the finite primary fossil resources available on Earth. The forecast of population growth over the next 3 decades is a very strong incentive for the identification of alternative primary resources other than petro-based ones. In contrast with fossil resources, renewable biomass is a virtually inexhaustible reservoir of chemical building blocks. Shifting the current industrial paradigm from almost exclusively petro-based resources to alternative bio-based raw materials requires more than vibrant political messages; it requires a profound revision of the concepts and technologies on which industrial chemical processes rely. Only a small fraction of molecules extracted from biomass bears significant chemical and commercial potentials to be considered as ubiquitous chemical platforms upon which a new, bio-based industry can thrive. Owing to its inherent assets in terms of unique process experience, scalability, and reduced environmental footprint, flow chemistry arguably has a major role to play in this context. This review covers a selection of C₂ to C₆ bio-based chemical platforms with existing commercial markets including polyols (ethylene glycol, 1,2-propanediol, 1,3-propanediol, glycerol, 1,4-butanediol, xylitol, and sorbitol), furanoids (furfural and 5-hydroxymethylfurfural) and carboxylic acids (lactic acid, succinic acid, fumaric acid, malic acid, itaconic acid, and levulinic acid). The aim of this review is to illustrate the various aspects of upgrading bio-based platform molecules toward commodity or specialty chemicals using new process concepts that fall under the umbrella of continuous flow technology and that could change the future perspectives of biorefineries.

Contribution to the production and use of biomass-derived solvents – a review

In this review key processes for the synthesis of greener or more sustainable solvents derived from renewable sources (saccharides, lignocellulose and triglycerides) are discussed. It is shown that a series of platform chemicals such as glycerol, levulinic acid and furans can be converted into a variety of solvents through catalytic transformations that include hydrolysis, esterification, reduction and etherification reactions. It was also considered several aspects of each class of solvent regarding performance within the context of the reactions or extractions for which it is employed.