SCIENCE & TECHNOLOGY acid groups allows for all kinds of fascinating new chemistry," notes Leo E. Manzer, who recently visited the Le Calorie facility. Manzer retiredfromDuPont last year and is now president of consulting firm Catalytic Insights, Wilmington, Del. At DuPont, he spent several years studying the conversion of levulinic acid to various derivatives. Manzer is particularly interested in developing pyrrolidones, which are used as solT'S WIDELY ANTICIPATED THAT WITHIN Levulinic acid can be produced in yields vents, surfactants, agricultural intermediates, a few decades the world's crude oil ofup to 70%, or about 0.5 kg per kg of cellu- ionic liquids, and nylon intermediates. This and natural gas supplies will no longer lose, along withformicacid and furfural n family of heterocyclic compounds can be be sufficient to meet global needs for as valuable by-products, Fitzpatrick made by catalytic reaction of levutransportation, energy, and chemi- says. Ligninfromthe starting ma- HO linic acid or its esters with low-cost cal products. One primary solution is the terial is another by-product and is sources of nitrogen such as amines development of biorefineries—facilities degraded to a carbon-rich char duror nitriles, he notes. that use chemical or biological processes ing the process. The material can be Levulinic acid Biomass-based feedstocks will to convert sugars, starch, or cellulose from burned or gasified to generate electricity to become more important, Manzer believes, dedicated crops, agricultural residues, or help run the plant. Biofine received a 1999 as companies like DuPont continue to seek municipal waste into basic chemicals that Presidential Green Chemistry Challenge new ways to improve efficiencies and keep in turn can be refined to make fuels, plastics, Award for developing the technology and down costs. For example, DuPont has a goal agricultural chemicals, and more. demonstrating it in a pilot plant. to derive 25% of its revenues from nondeBioethanol, biodiesel, and biomass-deUsed for years in food, fragrance, and spe- pletable resources by 2010. rived plastics have already hit the market- cialty chemical applications, levulinic acid In identifying their top 12 biorefinery place. Now, it's basic chemical feedstocks' is a precursor for methyltetrahydrofuran, chemicals, DOE scientists started with a turn to go green. y-valerolactone, and ethyl levulinate, which list of more than 300 potential compounds. The Department of Energy, as part of its can all be blended with diesel or gasoline to They narrowed the list down through an Biomass Program in the Energy Efficiency create cleaner-burning fuels, Fitzpatrick iterative process that considered the com& Renewable Energy Office, completed a says. Another derivative, diphenolic acid, pounds' compatibility with existing petproject two years ago that identiw rochemical processing, technical | complexity of the syntheses from fied 12 building-block chemicals i biomass, known market potential, as targets for biorefineries (C&EN, § and other factors. The 12 molecules May 31,2004, page 31). The first § have three to six carbon atoms and commercial-scale biomass-based g multiple functional groups as well plant to produce one of these chem< as high potential to be converted to icals, levulinic acid, has been built s new families of compounds. in Caserta, Italy, by Le Calorie, a subsidiary of Italian construction Unofficially, glycerol was the first firm Immobilgi. The 3,000-tonof the top 12 chemicals to achieve per-year plant, part of an ecological commercial development as a bioindustrial park, is being tested and mass-derived feedstock to make is expected to go into full producpropylene glycol and other prodtion in the next few months. ucts. But glycerol is a by-product of the esterification of triglycerides The Le Calorie plant produces in vegetable oil to make methyl eslevulinic acid from cellulose gleaned ters, the principal components of from local tobacco bagasse and pabiodiesel, and it isn't made directly per mill sludge through a process BIOMASS BOOM Fitzpatrick poses at the main from biomass on a commercial scale developed by Biofine Renewables, reactor complex of Le Calorie's plant in Caserta, Italy (C&EN, July 10, page 24). Besides Waltham, Mass. Biofine, a compa- The plant produces levulinic acid from tobacco plant levulinic acid and glycerol, the other nyformedin 1988 to commercialize residue and paper mill sludge. DOE compounds are 1,4-diacids technology developed by chemical engineer Stephen W. Fitzpatrick, licensed its is a potential replacement for suspected (succinic, fumaric, and malic), 2,5-furandilevulinic acid process to Le Calorie. endocrine disrupter bisphenol A in the pro- carboxylic acid, 3-hydroxypropionic acid, The Biofine process uses dilute sulfuric duction ofpolycarbonate resins. Diphenolic aspartic acid, glucaric acid, glutamic acid, acid at 220 °C to hydrolyze cellulose from acid is particularly interesting because it al- itaconic acid, 3-hydroxybutyrolactone, soressentially any plant source into sugars, lows formation of graft copolymers rather bitol, andxylitol/arabinitol. The Le Calorie plant is evidence that which are further transformed to levulinic than the usual linear polycarbonates, Fitzacid, Fitzpatrick explains. Key to the pro- patrick adds. Yet another valuable deriva- developing biorefineries is "not just a pipe cess, which takes only about 20 minutes, tive is 5-aminolevulinic acid, a high-volume dream," Manzer says. "We truly can refine biomass to create is a two-stage reactor design that favors biodegradable herbicide. formation of levulinic acid over a series of "Levulinic acid is nontoxic, and the bi- fuels and value-added chemicals," Fitzpatother possible products. functionality of the keto and carboxylic rick adds.—STEVE RITTER
BIOREFINERY GETS READY TO DELIVER THE GOODS
Italian levulinic acid facility is first to make targeted biomass-based chemical feedstocks
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