2007 Annual Report 1a.Objectives (from AD-416) Biodiesel is an alternative diesel fuel derived from vegetable oils, animal fats or used oils. While it is competitive with (in some aspects even technically superior to) conventional, petroleum derived diesel fuel, its use is still affected by several technical issues that hinder more widespread commercialization. Therefore, this project proposes to improve the combustion characteristics and fuel properties of vegetable oils (emphasizing soybean oil) and their derivatives as alternative diesel fuels, extenders, and additives in the operation of compression ignition (diesel) engines for on road and off road applications. Fatty derivatives will be utilized for performance enhancement and exhaust emission reduction (e.g. nitrogen oxides). Specific objectives for this project include: 1) Improved cold weather start up and operability performance. 2) Novel fuel formulations that reduce regulated exhaust emissions such as nitrogen oxides. 3) Improvement of fuel quality through enhanced oxidative stability and development of new, rapid analytical methods for assessing biodiesel fuel quality. 4) Development of specialty chemicals from biodiesel co-products. 1b.Approach (from AD-416) Improve the fuel properties and combustion characteristics of vegetable oils (emphasizing soybean oil) and their derivatives as alternative fuels, extenders, and additives in the operation of compression ignition (diesel) engines for on road and off road applications. Address technical problems identified by stakeholders and customers. Specific objectives for this project include: develop new alternative fuel formulations with improved cold weather start up and operability performance without compromising fuel quality as defined by appropriate standard fuel specifications; develop alternative fuel formulations with improved combustion performance that reduces harmful, regulated exhaust emissions such as nitrogen oxides, carbon monoxide and particulate matter; develop new biodiesel formulations with improved storage stability with respect to oxidative degradation; develop rapid instrumental methods for monitoring effects of degradation on biodiesel fuel quality during storage, as defined by appropriate standard fuel specifications; identify and develop novel specialty chemicals that may be prepared from glycerol, mono, and diacylglycerols as marketable co products of biodiesel production. 3.Progress Report Research continued towards the overall goals of enhanced understanding of factors governing biodiesel fuel properties and of developing biodiesel fuels with improved fuel properties. In this area, numerous factors were investigated including low-temperature behavior (kinematic viscosity, melting points, freezing point depression, the effects of contaminants), effects of blending with ultra-low sulfur diesel (ULSD) fuels, oxidative stability analysis by three separate methods and cetane number as indicator of fuel ignition and combustion. New additives for improving cold flow properties were developed. Other work included monitoring of the transesterification reaction through which biodiesel is produced, assessing the composition of used cooking oils, and exploring the utility of partially hydrogenated soybean oil methyl esters as potential biodiesel fuel. Collaborated with Alternative Aviation Fuels LLC (Rye Brook, NY) on development of a pilot-scale dry fractionation process for improving the cold flow properties of biodiesel. Collaborated with Iowa State University/University of Idaho on biodiesel education courses. Collaborated with Southwest Research Institute (SwRI) on cetane testing of fatty esters. 4.Accomplishments The following accomplishments each address research under the "Biodiesel" component of National Program 307 Bioenergy and Energy Alternatives. Effects of contaminants on cold flow properties. Storage of biodiesel during cold weather raised concerns with respect to precipitation of trace concentrations of contaminants "leftover" from the production process. Effects of small concentrations of one class of contaminant, monoglycerides, on cold flow properties of biodiesel from soybean oil were determined. Differential scanning calorimetry (DSC) scans were employed to measure phase transitions and other phenomena associated with freezing of samples. Methods were developed for removing solids from affected biodiesel storage tanks owned by a local fuel distributor. Results increased the understanding of how trace concentrations of contaminants may affect fuel quality during long-term storage. Biodiesel blends with ULSD diesel. Mandated reductions in sulfur content of petrodiesel has raised questions among stakeholders and consumers about what happens to fuel properties when ultra-low sulfur diesel (ULSD, 0.000015 percent sulfur content) is blended with biodiesel. Cloud point, pour point, viscosity (thickness), density and other fuel properties were measured for low-level (less than five percent) and mid-level (up to 20 percent) blends of biodiesel from soybean oil in ULSD. Results from this work will be useful to stakeholders, scientists and engineers owing to the scarcity of data relating the affects of blending biodiesel and ULSD in the scientific literature. Effects of temperature on oxidation of biodiesel. The ASTM fuel specification for biodiesel includes a minimum induction period, also known as oil stability index (OSI), for the onset of oxidative degradation. OSI may be problematic because it is measured at high constant temperature to accelerate its analysis and effects of temperature are not sufficiently understood since biodiesel is generally stored at significantly lower temperatures. OSI of biodiesel from soybean oil and used cooking oil feedstocks were analyzed at various temperatures and the results linearly correlated by two mathematical models. One of the models was interpreted to describe reaction kinetics and calculate responses at lower temperatures. This work contributed towards the understanding of the effects of temperature on oxidation of biodiesel in standardized tests. It also raised questions on the validity of employing responses measured at high temperatures and interpreting them analogously at lower, more realistic storage temperatures. Glycerol polyesters. The development of biobased products from biodiesel derived glycerol continued with the preparation of several polyesters obtained by the condensation of glycerol with adipic acid, azelaic acid, suberic acid, and sebacic acid. These reactions did not require a catalyst and were completed at modestly elevated temperatures up to 125 deg C. These polymers are considered biodegradable and have shown promise as weed barriers or mats and can also serve as controlled-release materials to deliver fertilizer or pesticides in agricultural applications. Glycerol polyesters could replace common petrochemical polymers such as polyethylene or polypropylene. Large quantities of glycerol continue to be produced during the conversion vegetable oils into biodiesel fuels. This application would provide an outlet for the surplus glycerol. Ultraviolet (UV) screen components. The esterification reaction of glycerol with cinnamic acid and related ultraviolet (UV) absorbing compounds was investigated to determine conversion rates for potential commercialization. These materials will not be absorbed into the skin from a topical formulation and do not present the health risks associated with sunscreen components that are made from fatty or oil compounds. New results on biodiesel low-temperature behavior. Biodiesel and numerous fatty esters which can comprise biodiesel were evaluated for their kinematic viscosity behavior at low temperatures down to -10 deg C and melting points of esters with low melting points were determined. Kinematic viscosity measurements were carried out in increments of 5 deg C. A new index for assessing low-temperature viscosity behavior was developed. The results aid in developing a biodiesel fuel with composition modified for optimizing fuel properties. Structural effects in biodiesel oxidation. Since exposure to the oxygen in air is a major factor affecting the fuel quality of commercial biodiesel, fatty esters were subjected to oxidation by means of accelerated oxidation tests. The tests used were the oil stability index and Rancimat. The two methods generate comparable data, with no neat unsaturated fatty compound achieving the requirements of oxidation stability specifications in standards. The results will contribute significantly in devising biodiesel fuels with improved fuel properties. Cetane numbers determined. A variety of fatty esters not previously tested for their cetane numbers were evaluated in this respect. The cetane number is a prime diesel fuel quality index related to ignition and combustion, with long-chain fatty esters performing well in this respect. The new data established more closely which kinds of fatty esters have cetane numbers meeting the specifications in biodiesel standards. The new data will assist in establishing which fatty esters should be enriched in biodiesel fuels with enhanced fuel properties. New cold flow additives for biodiesel. Several fatty derivatives with bulky moieties were synthesized from oleic acid by treatment of an assortment of alkyl oleates with a variety of alcohols in the presence of sulfuric acid catalyst to provide a series of alpha-hydroxy ethers. The materials were analyzed for low temperature behavior through cloud-point and pour-point determination. Generally, the 2-ethylhexoxy ethers of oleates containing bulky head groups were found to have the best low-temperature performance. These results demonstrate that agricultural-based materials have potential as cold-flow additives for biodiesel. Partial hydrogenation of soybean oil methyl esters. Partially hydrogenated soybean oil methyl esters (PHSME) were prepared in a two-step sequence (hydrogenation and transesterification) in an effort to satisfy the European Union biodiesel specification (EN 14214). A number of physical properties of the resultant methyl esters were measured and it was concluded that PHSME is acceptable for use as biodiesel fuel both in the European Union and the United States of America. These results demonstrate that soybean oil-derived biodiesel, after partial hydrogenation, is acceptable for use in the large European biodiesel market. 5.Significant Activities that Support Special Target Populations None 6.Technology Transfer Number of new CRADAs and MTAs 2 Number of active CRADAs and MTAs 2 Number of invention disclosures submitted 1 Number of web sites managed 1 Number of non-peer reviewed presentations and proceedings 18 Number of newspaper articles and other presentations for non-science audiences 9 Review Publications Dunn, R.O. 2006. Oxidative stability of biodiesel by dynamic mode pressurized-differential scanning calorimetry (P-DSC). Transactions of the ASABE. 49(5):1633-1641. Knothe, G.H. 2006. Analyzing biodiesel: Standards and other methods. Journal of the American Oil Chemists' Society. 83(10):823-833. Moser, B.R., Erhan, S.Z. 2006. Synthesis and evaluation of a series of alpha-hydroxy ethers derived from isopropyl oleate. Journal of the American Oil Chemists' Society. 83(11):959-963. Moser, B.R., Haas, M.J., Winkler, J.K., Jackson, M.A., Erhan, S.Z., List, G.R. 2007. Evaluation of partially hydrogenated methyl esters of soybean oil as biodiesel. European Journal of Lipid Science and Technology. 109:17-24. Moser, B.R., Erhan, S.Z. 2007. Preparation and evaluation of a series of alpha-hydroxy ethers from 9,10-epoxystearates. European Journal of Lipid Science and Technology. 109:206-213. Vaughn, S.F., Holser, R.A. 2007. Evaluation of biodiesels from several oilseed sources as environmentally-friendly contact herbicides. Industrial Crops and Products 26(1):63-68. Knothe, G.H. 2007. Some aspects of biodiesel oxidative stability. Fuel Processing Technology. 88:677-699.