Levulinic acid Biofine process

The most widely used approach for producing levulinic acid is the direct hydrolysis of biomass or carbohydrates, catalyzed by aqueous acid.478,480 483 However, this forms large amounts of side products and intractable materials, requiring an expensive separation that drives up its cost. Several years ago, a new process developed by the Biofine Corporation eliminated many of the existing production problems. The Biofine process... 

The Biofine process produces levulinic acid, furfural and formic acid from lignocellulose in a two-step process using dilute sulfuric acid as a catalyst [45], The first step depolymerises the polysaccharides and converts the resulting 6-carbon sugars into hydroxymethylfurfural by a dehydration reaction at 210-220 °C and 25 bar. The second step converts hydroxymethylfurfural to the products at 190-200 °C and 14 bar (Scheme 1). 

Paper mill sludge (as well as other forms of cellulose) can be converted to levulinic acid in 70-90% yield by hydrolysis to glucose followed by controlled heating (12.14) in a process developed by Biofine, Inc.41... 

Hayes, D.J., Fitzpatrick, S.W., Hayes, M.H.B., and Ross, J.R.H. (2005) The biofine process - production of levulinic acid, furfural, and formic acid from lignocellulosic feedstocks, in Eiorefineries Industrial Processes and Products, vol. 1 (eds B. Kamm, P.R. Gruber, and M. Kamm), Wiley, Weinheim, Germany, pp. 139-164. 

Entry 13 describes another high yielding approach to LA that involves the intermediacy of CMF 2, the preparation of which was covered in Sect. 3 of this chapter. Using com stover as an example, submission to the CMF process (biphasic aq. HCl/solvent reaction, 80°C, 3 h) gives CMF in 80% yield, during which levulinic acid is co-produced in 8% yield. Hydrolysis of the CMF at 190°C for 20 min provides a 91% yield of LA, for a net conversion from biomass of 81% over two steps. The Biofine and CMF methods are co-rendered graphically in Scheme 23. 

The acid catalysed hydrolysis of cellulose-containing biomass to levulinic acid (LA) has been known for a number of years but yields are low and tars are formed. However, by careful control of the temperature and pressure (i), Biofine Inc., has been able to develop a high yield process in a pilot plant. Commercial scaleup at several locations is in development (4). Although the literature contains numerous references to LA chemistry, the scope is limited. We now report a number of new reactions of levulinic acid. 

A second very large potential market for levulinic acid is in the production of the photodynamic pesticide delta aminolevulinic acid (DALA). DALA is the active ingredient in a range of environmentally benign broad-spectrum herbicides and insecticides under development at the University of Illinois, Urbana Champaign (14). Biofine, in conjunction with the National Renewable Energy Laboratory (NREL), Golden, CO has developed and patented a process for conversion of levulinic acid to DALA in reasonable yield (75). 

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