Chemicals, biomass levulinic acid

The top 12 building block molecules from biomass, identified by the DOE study (2) present a significant new opportunity for catalytic conversion to a wide variety of specialty and commodity chemicals. Using levulinic acid as an example we have shown that rich new chemistry is possible. Pryrrolidones, reactive acrylic monomers and fuel additives are readily obtained. 

In some cases, the hydrolysis reaction liberates the sugars from the biomass and converts them directly into derivatives such as furfural, hydroxymethyl furfural and/or levulinic acid. These derivatives can be further converted into various chemical intermediates. We will not discuss these further conversions as they are extensively reported in the literature, e.g., for furfural [15, 44], hydroxymethyl furfural [15, 44, 50] and levulinic acid [15, 44-47]. 

DOE, Energy, Efficiency and Renewable Energy, Top value added chemicals fi om biomass. Screening for potential candidates from sugars (a) Levulinic acid, pp. 45-48 (b) 3-Hydroxypropionic acid (3-HPA), pp. 29-31 (c) Four-carbon 1,4-diacids, pp. 22-25 (d) Itaconic acid, pp. 42-44 nrel.gov/docs/fy04osti/ 35523.pdf, 67 pp. 

Biorefinery includes fractionation for separation of primary refinery products. The fractionation refers to the conversion of wood into its constituent components (cellulose, hemicelluloses and lignin). Processes include steam explosion, aqueous separation and hot water systems. Commercial products of biomass fractionation include levulinic acid, xylitol and alcohols. Figure 3.3 shows the fractionation of wood and chemicals from wood. 

When the structure of biomass components has to be quite drastically rearranged compared to the building blocks needed, synthesis gas or different sugars can serve as platform chemicals. The latter can be converted, for example, to sugar-derived building blocks (Figure 2.2.3) - that is, to glycerol, sorbitol, levulinic acid, and furfural. 

In this section, we seek to identify materials that are the reasonable first structures to arise from biomass deconstruction, and to describe how chemically catalyzed processes are being developed for their production. For that reason, commercially practiced processes that use catalysis, such as the reduction of glucose to sorbitol, are mentioned only briefly or not at all. Chemical catalysis will certainly play an additional role in the further conversion of these initial building blocks into secondary intermediates or final marketplace products (e.g., oxidative conversion of levulinic acid into succinic acid), but such multistep possibilities are outside the scope of this discussion. 

The rehydration product of HMF, levulinic acid, is also regarded as a potential biomass derived organic compound [35, 39,40]. Levulinic acid could be utilized as feedstock for several large volume chemicals (Fig. 7), e.g., methyltetrahydrofuran and levulinate esters (fuel additives), delta-amino-levulinic acid (herbicide), and diphenohc acid (replacer for bisphenol A for polycarbonates). 

Abstract The synthesis and chemistry of 5-(hydroxymethyl)furfural (HMF), 5-(chloromethyl)furfural (CMF), and levulinic acid (LA), three carbohydrate-derived platform molecules produced by the chemical-catalytic processing of lignocellulosic biomass, is reviewed. Starting from the historical derivation of these molecules and progressing through modem approaches to their production from biomass feedstocks, this review will then survey their principal derivative chemistries, with particular attention to aspects of commercial relevance, and discuss the relative merits of each molecule in the future of biorefining. 

Keywords 5-(Chloromethyl)furfural 5-(Hydroxymethyl)furfural Biomass Biomass derivatives Biorefinery Catalysis CMF Green chemistry HMF Levulinic acid Platform chemicals Renewable chemistry... 

Galletti AMR, Antonetti C, De Luise V, Valentini G (2011) Conversion of biomass to levulinic acid, a new feedstock for the chemical industry. Chimica e I lndustria 93 112-117... 

The utilization of cellulose as the raw material for production of monomers and polymers is reviewed and discussed. As the most abundant nonfood biomass resource on Earth, cellulose can be catalytically depolymerized to glucose, while glucose is a versatile starting material for a large variety of platform chemicals including ethanol, lactic acid, HMF, levulinic acid, sorbitol, succinic acid, aspartic acid, glutamic acid, itaconic acid, glucaric acid, and so oti. These platforms can be used as monomers directly or further converted to polymerizable monomers for polymer synthesis. 

Alonso et have eliminated pre-treatment steps to fractionate biomass. They made use of certain composition in biomass to obtain fuels and chemicals, and the rest of fraction was separated. The work used gamma-valerolactone (GVL) as solvent, and the cellulosic fraction of lignocellulosic biomass can be converted into levulinic acid (LA), while at the same conditions the hemicellulose fraction can be converted into furfural. The furfural can be separated by distillation during the reaction or can be kept in the reactor and subsequently processed to produce furfutyl alcohol and LA. The lignin was solubilized in the GVL and separated. This process not only obtains the production of fuels and chemicals by utilization of hemicellulose and cellulose, but also it benefits from the elimination of pre-treatment and extraction/separation steps. 

Levuhnic acid is one of the products of selective dehydration of cellulosic biomass feedstocks. Levuhnic acid is produced when six-member ring carbohydrates derived from ceUulose are subjected to acid-catalyzed dehydration conditions (Fig. 9.6) [4, 43]. The other main product of this reaction is formic acid. Although levulinic acid has some potential use as a solvent or in the production of industrial and pharmaceutical chemicals, its current market is minimal [4]. Therefore, the conversion of levulinic acid to a directly usable biofuel has become an important area of interest. In particular, esterification, oxidation, hydrogenation, reductive amination, condensation, and enzymatic conversion have been tested as potential methods to produce useful compounds from levulinic acid [4,44,45]. 

Biotechnology continues to be an important contributor to the biorefinery, especially for the conversion of carbohydrates. The paper by Richard describes a new approach for the fermentation of C sugars, providing methodology for more efficient conversion of biomass carbohydrates to EtOH. The contribution from Nakas discusses the bioproduction of polyhydroxyalkanoates using levulinic acid as a carbon source. Stipanovic describes new approaches for using hemicellulose as a chemical feedstock. 

The US Department of Energy has recently issued a report (2) outlining the top 12 building block chemicals that can be produced from sugars via biological or chemical conversions. They are shown in Table III. Levulinic acid is one of the key building blocks and has been the focus of some of our research at DuPont. This paper will outline some of our research to illustrate the potential for new chemical transformations of these biomass building blocks. 

Waste biomass (poplar sawdust, wheat straw, paper sludge, etc.) Hydrothermal and chemical Hydrothermal conversion of feedstock in the presence of an acid catalyst Levulinic acid Galletti et al. (2012)... 

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