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Title: Biodiesel Fuel Quality and the ASTM Standard

item Knothe, Gerhard

Submitted to: Meeting Abstract
Publication Type: Proceedings
Publication Acceptance Date: 9/22/2009
Publication Date: 9/22/2009
Citation: Knothe, G.H. 2009. Biodiesel Fuel Quality and the ASTM Standard [abstract]. Proceedings of the 16th International Oil Palm Conference and Expo, Cartagena, Columbia.

Interpretive Summary:

Technical Abstract: Biodiesel is usually produced from vegetable oils, animal fats and used cooking oils with alternative feedstocks such as algae receiving increasing interest. The transesterification reaction which produces biodiesel also produces glycerol and proceeds stepwise via mono- and diacylglycerol intermediates. As a result, small amounts of glycerol, lipid starting material, and intermediates may remain in the final biodiesel product even after purification. Depending on the feedstock, other materials originally contained in a feedstock may carry over into biodiesel. The fatty acid profile of a biodiesel fuel corresponds to that of its feedstock. Due to the variety of feedstocks with different fatty acid profiles this results in different properties of the fuel. The overall quality of a biodiesel fuel is affected by all of these issues. Therefore, these issues are addressed by various specifications in the ASTM (American Society for Testing and Materials) as well as other biodiesel standards. The ASTM standard has also received numerous updates over time. The various specifications in the ASTM standard as well as some differences to other standards are discussed.