Alkyl levulinates

Notably, ethyl or butyl levulinates could be entirely derived from cellulosic feedstocks, without the need for additional hydrogen. However, the chemical properties of these levulinates, including their capacity to act as solvents, would require modification of the materials used in today s combustion systems. Furthermore, longterm road trials employing alkyl levulinate as blends or even as a pure biofuel would be necessary to assess the resulting overall engine efficiency and exhaust emissions. 

Alkyl levulinate esters 72 can be prepared by homogeneous acid-catalyzed Fischer esterification of LA [188], under solid acid catalysis [189, 190], by acid-catalyzed... 

As an alternative to landfilling or high-temperature incineration, the acid-catalyzed decomposition in alcohol efficiently and safely converts the composite materials to alkyl levulinate at moderate temperatures. The product composition obtained by heating particle board chips in ethanol with sulforic acid catalyst for 30 min at 200°C was similar to that obtained from ordinary wood treatment. The charcoal product was removed by filtration the ethanol, water, and ethyl formate product flash-distilled and the ester levulinate separated from the resinous product by extraction into diethyl ether. In this case, the resinous products also contained the UF binding resins that were initially present in the waste board. The UF resin-derived components were intimately mixed with or chemically attached to the lignin resin there was no way to extract and separate the lignin from the UF component. 

Yields for several alcohols were determined for the reaction of particle board at 190°C for 40 min reaction time (2% sulfuric acid catalyst). The results for the various alcohols are given in Table II. Methanol and ethanol are essentially equivalent in forming the alkyl levulinate on a weight percent basis. For longer-chain alcohols, the yields drop off substantially with size. In the case of the aminoethanol, methoxyethanol, and hexanol, the solid material is recovered as brown granules and cannot be dried easily. No alkyl levulinate is found in the solvent phase. By comparison with water as the solvent, the charcoal yield was 46 wt% and the levulinic acid was 18% as determined by gas chromatography. 

Table II. Formation of Alkyl levulinates in Reactions of Particle Board in...

A major goal for promoting commercialization of the alcohol processing of waste particle board and plywood is the expansion of markets for alkyl levulinates. The major current market for alkyl levulinates is in fragrances, where the ethyl levulinate has a value of about 10/lb. Butyl levulinate is also used but the market is relatively small for both esters. 

Levulinic acid as platform molecule to oxygenated fuels alkyl levulinates and valeric biofuels... 

Low-alkyl levulinates, and particularly ethyl levulinate (EL), can be advantageously used as oxygenated biofuels. They can be easily obtained by esterification of levulinic acid with a lower alcohol such as ethanol. Such reaction occurs even at room temperature, but the rate is very low and needs to be accelerated by either increasing... 

However, as previously discussed for alkyl levulinates, this approach would necessitate a source of high-purity levulinic acid. Therefore, research studies have lately... 

Intrinsic energy of FA can also be upgraded by means of etherification with short-chain alcohols, transformation of alkyl-furfuryl ethers into alkyl levulinates and esterification with short alkyl carboxylic acids. In the following, we wiU discuss the most... 

Geboers, J., Wang, X., de Carvalho, A.B., Rinaldi, R., 2014. Densification of biorefinery schemes by H-transfer with Raney Ni and 2-propanol a case study of a potential avenue for valorization of alkyl levulinates to alkyl y-hydroxypentanoates and y-valerolactone. Journal of Molecular Catalysis A Chemical 388—389, 106—115. 

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