Sugar acids levulinic acid

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. 

Jeong G-T, Park D-H (2010) Production of sugars and levulinic acid from marine biomass Gelidium amansii. Appl Biochem Biotechnol 161 41-52... 

Starch and sugar Starch crops, sugar crops and potatoes Saccharose and starch Glucose and fructose Ethanol, lactic acid, 1,3-propanediol, succinic acid, levulinic acid, furans, 3-HP and isoprene... 

While for the production of lactic acid a mechanism is commonly claimed that involves the glucose isomerization to fructose, retro-aldol condensation of fructose followed by the triose isomerization to lactic acid, all these reaction sentences being catalyzed by Lewis acid sites [160], the achieved data indicate that although Brpnsted acidity favors the hydrolysis of short olygomers, an excess in these species does not help a further transformation of glucose to lactic acid. Contrarily, Brpnsted acidity seems to be responsible for different side reactions as (1) dehydration of the sugars to levulinic acid and methyl-pyranoside [161] ... 

In the acid hydrolysis process (79—81), wood is treated with concentrated or dilute acid solution to produce a lignin-rich residue and a Hquor containing sugars, organic acids, furfural, and other chemicals. The process is adaptable to all species and all forms of wood waste. The Hquor can be concentrated to a molasses for animal feed (82), used as a substrate for fermentation to ethanol or yeast (82), or dehydrated to furfural and levulinic acid (83—86). Attempts have been made to obtain marketable products from the lignin residue (87) rather than using it as a fuel, but currently only carbohydrate-derived products appear practical. 

HMF is an important versatile sugar derivative and is a key intermediate between bio-based carbohydrate chemistry and petroleum based industrial organic chemistry (1, 2). The most coimnon feedstock for HMF is fructose and reactions are carried out in water-based solvent systems using acid catalysis (3,4). HMF is unstable in water at low pH and breaks down to form levulinic acid and formic acid, resulting in an expensive HMF recovery process. In strongly polar organic co-solvents, such as dimethylsulfoxide (DMSO), levuhnic acid formation is reduced and HMF yields are improved (5). 

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]. 

It has been shown also that the concentration of sucrose is a critical factor and that to obtain the highest yields very dilute solutions are necessary. Thus Fig. 1 shows the relative yields at different concentrations of sucrose heated with hydrobromic acid, all experiments being carried out under similar conditions. The highest yield of levulinic acid, weighed as crude material, was 79% of the theoretical and was obtained when the concentration of sucrose was 3%. Ploetz has also used the hydrobromic acid method to make levulinic acid and records a yield of 69% of the theoretical from crude sugar, 75% from glucose and 64 % from starch. 

The major soluble components of acid hydrolysates are sugars, such as xylose, glucose, and cellobiose furfurals, such as furfuraldehyde and hydroxymethyl furfural and organic acids, such as levulinic acid, formic acid, and acetic acid (13). When natural sources of cellulose are acid-hydrolized, numerous products can result, largely because of the hemicellulose materials. These make it difficult to produce a relatively pure sugar product and limit the utility of the acid hydrolysis process. 

Levulinic acid is formed by the treatment of six-carbon sugar carbohydrates from starch or lignocellulosics with acids, or by add treatment plus a reductive step of five-carbon sugars derived from hemicellulose. Levulinic add can serve as a building block for the synthesis of many derivatives of interest may be the selective oxidation to succinic and acrylic add. [i-Acetylacrylic add could be used in the production of new acrylate polymers. 

Method Fermentable sugars Levulinic acid Acetic acid Formic acid Furfural HMF Total phenolics ... 

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. 

Fig. 2 -31. Reactions of sugars in the presence of concentrated mineral acids, (a) Pentoses (R = H) yield furfural and hexoses (R = CH2OH) hydroxymethylfurfural. (b) On further heating hydroxymethylfurfural is fragmented under liberation of formic acid. The rest of the molecule is rearranged to levulinic acid, which is lactonized to form a- and /3-angelica lactones.

The liquid portion of biomass-derived process samples may also contain carbohydrate degradation products, such as 5-(hydroxymethyl)-2-furaldehyde (HMF), levulinic acid, and furfural, as well as other components of interest, such as organic acids and sugar alcohols. Portfolio methods are available for the quantitative measurement of these degradation products and byproducts of polymer hydrolysis. 

The removal of water from initially formed biomass sugars is an important process for the production of primary biorefinery building blocks. Of particular interest are 5-hydrox-ymethylfurfural and levulinic acid (from the dehydration of glucose or other C6 sugars) and furfural (from xylose dehydration). Recent research has led to new catalytic processes for the production of each of these materials. 

Levulinic Acid. Dehydration of glucose or other monomeric and polymeric C6 sugars leads to the direct formation of levulinic acid (LA) as a potential primary building block for the biorefinery, and several reviews have described its potential commercial utility 477,478 The preparation of levulinic acid is not difficult, although the mechanism of its formation from carbohydrates is complex, and offers several alternative decomposition pathways (equation 3).479... 

Dahlmann, J., Hydrolytic method for the production of levulinic acid and its derivatives from biomass and sugars. Chemische Berichte 1968, 101, 4251—4253. 

Levulinic Acid. Levulinic acid is formed by the acid catalyzed degradation of hexose sugars via the intermediacy of hydroxymethylfurfural (145). Although its formation was reported as early as 1836 (143), the mechanism of its formation has been studied at least as recently as 1985 (147). 

The only practical methods for preparing levulinic acid depend upon the action of mineral acids upon carbohydrates, a reaction discovered by Grote and Tollens,1 who heated cane sugar with dilute sulfuric acid. The method above described is essentially that of Conrad,2 descriptions of which frequently have appeared 3 in the subsequent literature. The use of vacuum distillation was suggested by Kent and Tollens.4 Levulinic acid has also been prepared from starch by the action of hydrochloric add. ... 

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