Fatty acid profile of alternative feedstocks for biodiesel production and implications for fuel properties

Authors: Moser, Bryan

Submitted to: American Chemical Society National Meeting
Publication Type: Abstract Only
Publication Acceptance Date: 3/18/2018
Publication Date: 3/18/2018
Citation: Moser, B.R. 2018. Fatty acid profile of alternative feedstocks for biodiesel production and implications for fuel properties [abstract]. American Chemical Society National Meeting, March 18-22, 2018, New Orleans, LA. Paper No. ANYL 269.

Interpretive Summary:

Technical Abstract: Feedstock accounts for approximately 80% of biodiesel production expenses when commodity lipids such as soybean oil are utilized. Furthermore, commodity lipids have competing food-related applications. Consequently, low-cost alternatives that do not displace existing food production are of interest to improve the economics of biodiesel production while simultaneously augmenting lipid supply. Herein the fatty acid profiles of alternative feedstocks are described, which include camelina, corn dried distillers’ grains with solubles, coriander, field pennycress, Osage orange, seashore mallow, and wild Brazilian mustard. Generally, the most common fatty acids identified via GC-FID were linoleic, oleic, linolenic, and palmitic acids. Erucic acid was the most common constituent in field pennycress and wild Brazilian mustard whereas petroselenic acid predominated in coriander. Because cold flow, oxidative stability, kinematic viscosity, and cetane number are strongly influenced by fatty acid composition, fuel properties of the corresponding methyl esters were determined and compared against the biodiesel fuel standards ASTM D6751 and EN 14214. Coriander methyl esters were within the limits of the aforementioned standards whereas esters from other feedstocks failed one or more fuel specifications. For instance, methyl esters enriched in polyunsaturated fatty esters exhibited low oxidative stability, those with high amounts of saturated fatty esters displayed poor cold flow performance and those with very long chain constituents gave high kinematic viscosities. Such deficiencies can be ameliorated with performance-enhancing additives and/or with complementary blending strategies. In summary, alternative feedstocks are critical to the economics of the biodiesel industry, but fatty acid composition must be considered due to its impact on fuel properties.