1a. Objectives (from AD-416):
Objective 1: [addresses NP 307 Action Plan Problem Statements 3(c)(1), 3(c)(2) and 3(a)(4)] Develop new technologies that enable (1) commercial direct (‘in-situ’) production of biodiesel, and (2) commercially-preferred processes for the production of biodiesel from available, low-cost feedstocks. Objective 2: [addresses NP 307 Problem Statements 3(c)(1), 3(c)(2) and 3(a)(4)] Develop technologies that enable commercially-preferred technologies to remove performance-degrading biodiesel contaminants such as catalysts, sterol glucosides and sulfur. Objective 3: [addresses NP 307 Problem Statement 3(c)(5), and NP 306 Problem Statement 2c] Develop technologies that enable; (1) commercial production of hyperbranched polymer products from byproduct glycerol; and (2) commercially-viable and environmentally benign processes for new high-value industrial products made from fatty acids or the combination of fatty acids and lignin derivatives.
1b. Approach (from AD-416):
Develop technologies to use heterogenous catalysts to replace homogenous catalysts in the synthesis of biodiesel from free fatty acids and from glycerides in low quality feedstocks. Improve and scale-up methods newly develop method for biodiesel synthesis from trap grease. Using chromatographic and spectroscopic technologies, identify the structures of sulfur containing species contaminating biodiesel from low quality feedstocks and develop methods for their removal. Using enzymatic catalysis, remove sterol glucoside contaminants from vegetable oil based biodiesels. Develop new methods for the use of novel solid catalysts to modify fatty acids, in some cases through their combination with lignin degradation products generated by the pyroloysis of lignocellulosic feedstocks, to produce lubricants, personal care materials, and other functional lipids. Develop organic chemical methods to produce prepolymers from biodiesel glycerol and organic di-acids and use these to produce hyper-branched polymers. Determine the size and structures of these and determine their physical properties.
3. Progress Report:
An ARS technology for the direct production of biodiesel from raw agricultural materials was optimized, using soybeans as the substrate. Biodiesel recovery was maximized while reducing the use of chemical reagents. An economic model was constructed that allows potential industrial adopters to accurately assess the cost of constructing and operating a facility to produce biodiesel by this new technology. Biodiesel is subjected to nearly 20 Official Assays to ensure its quality. For the first time a method was created to standardize the test system employed to conduct one of these assays, that for Cold Soak Filtration time (CSFT). This standardization method will give greater uniformity and reliability to CSFT data, thereby helping to ensure the in-field performance of biodiesel. A previously developed method achieves chemical rearrangement of the fatty acids found in vegetable oils and animal fats, resulting in ‘branched’ structures that can be used to improve cosmetics, paints, and lubricants. Continuing studies have now resulted in a process for retaining/regenerating the activity of the rearrangement catalyst. This reduces catalyst use and improves the environmental friendliness of the reaction. In further work, the economic model for this fatty acid branching technique was modified to incorporate the impact of adopting the new catalyst regeneration technology. The resulting model highlighted the substantial savings that could be realized by adopting catalyst regeneration. Derivatives of fats and oils such as phenolic-branched-chain fatty acid products are potentially useful as lubricant additives and antioxidants. Researchers developed an efficient technology to join the fatty acids found in agricultural fats and oils with phenolic compounds, and means to purify the resulting products. Methods to analyze the physical properties of these new compounds were developed. This determination of properties will facilitate the identification of applications. To develop further outlets for the abundant glycerol co-product of biodiesel production, researchers examined the effects of infusing biobased polymers such as corn fiber gum, pectin, sugarcane bagasse and microcrystalline cellulose into gels and films produced from glycerol. The properties of the resulting hybrids make them potentially good candidates in agricultural and medicinal applications because of their abilities to absorb and desorb organic solvents. An innovative stepwise procedure for constructing fatty acid oligomers was developed. This approach is useful for incorporating branching units, which alter lubrication and rheology properties, at selected points in the chain. Several examples were prepared, viscosities of the materials were measured, and they compare well with other known lubricants. These new bio-based lubricants were also chemically modified to make them resistant to hydrolytic degradation. Such improved stability is rare in fat-derived materials, so this procedure may open the door to utilizing bio-based lubricants in harsh environments that have previously been amenable only to petroleum products.
Ngo, H., Dunn, R.O., Hoh, E. 2013. C18-unsaturated branched-chain fatty acid isomers: characterization and physical properties. European Journal of Science and Lipid Technology. 115:676-683.