2007 Annual Report
Objective 1: Develop methods for the conversion of agrimaterials to platform chemicals. There are two aspects to this objective: a) the oxidation of seed oils to platform chemicals such as diacids and hydroxyacids; and b) the design and development of better catalysts for regioselective transformations, including the selective addition of aromatics to the double bond of unsaturated fatty acids.
Objective 2: Develop commercially viable processes based on critical fluids to convert ligno-cellulosic materials to fermentable sugars as well as convert vegetable oils to high-value products. There are two sub-objectives to this objective: a) develop commercially viable processes based on critical fluids such as carbon dioxide (CO2), water and/or ethanol to pretreat ligno-cellulosic biomass prior to its conversion via enzymatic hydrolysis to fermentable sugars; and b) use CO2-based critical fluids to improve the commercial viability of processes for enzymatically converting vegetable oils to high-value products such as feruloylated monoacyl- and diacylglycerides. Critical fluid processes will be evaluated for enhancement of these conversions and integration with downstream recovery processes for these high-value products.
New objective for FY08: Fractionation and characterization of pyrolysis oil.
The second approach used a catalyst switching strategy to give basestocks of even lower trans fatty acid levels. In this method, soy, canola, high-oleic sunflower, and high-oleic safflower oils were hydrogenated to a specific point using a selective catalyst, then the catalyst was switched to a nonselective catalyst to further hydrogenate the product. This gave basestocks with trans fatty acid levels even lower than those using the first approach. Both of these strategies can be used with current industrial equipment and commercially available catalysts. Adoption of the second approach would not only give low trans fatty acid products, but could also increase the demand for crops grown on a limited number of acres. Expanded use of safflower oil should lead to expanded planting in areas where more profitable crops, such as corn and soybeans, do not perform as well.
Work on the catalytic conversion of vegetable oils has resulted in the preparation of new products from the oil isolated from Lesquerella and castor. Final characterization of these compounds and optimization of reaction conditions continue.
An apparatus for conducting carbon dioxide explosion experiments of ligno-cellusic materials has been constructed. Corn stover has been extracted with carbon dioxide in both a static as well as dynamic fashion using carbon dioxide. These materials will be subjected to hydrolysis and fermentation to determine differences in their subsequent ethanol yields.
A critical fluid fractionation column for purifying propyl esters from mono-, di-, and triglycerides was designed and built. This column was used to remove the esters without subjecting the mixture to heat and prevented acyl migration in the glycerides observed during vacuum distillation.
Eisenmenger, M., Dunford, N.T., Eller, F.J., Taylor, S.L., Martinez, J. 2006. Pilot scale supercritical carbon dioxide extraction and fractionation of wheat germ oil. Journal of the American Oil Chemists' Society. 10:863-868. Stevenson, D.G., Eller, F.J., Jane, J., Inglett, G.E. 2007. Starch structures and physicochemical properties of a novel beta-glucan-enriched oat hydrocolloid product with and without supercritical carbon dioxide extraction. American Journal of Food Technology. 2(4):248-256. Stevenson, D.G., Eller, F.J., Wang, L., Jane, J., Wang, L., Inglett, G.E. 2007. Oil and tocopherol content and composition of pumpkin seed oil in twelve cultivars. Journal of Agricultural and Food Chemistry. 55(10):4005-4013. Stevenson, D.G., Eller, F.J., Radosavljevic, M., Jane, J., Inglett, G.E. 2007. Characterization of oat products with and without supercritical carbon dioxide extraction. International Journal of Food Science and Technology. 42:1489-1496. Peterson, S.C., Eller, F.J., Fanta, G.F., Felker, F.C., Shogren, R.L. 2007. Effects of critical fluid lipid extraction on the gelatinization and retrogradation of normal dent cornstarch. Carbohydrate Polymers. 67(3):390-397.