Book Description

In support of the U.S. Dept. of Energy (DOE) Fuels Technologies Program Multiyear Program Plan Goal of identifying fuels that can displace 5% of petroleum diesel by 2010, the Nat. Renewable Energy Lab. (NREL), in collaboration with the Nat. Biodiesel Board (NBB) and with subcontractor Southwest Research Institute, performed a study of biodiesel oxidation stability. The objective of this work was to develop a database to support specific proposals for a stability test and specification for biodiesel and biodiesel blends. B100 samples from 19 biodiesel producers were obtained during Dec. 2005 and Jan. 2006 and tested for stability. Eight of these samples were then selected for additional study, including long-term storage tests and blending at 5% and 20% with a number of ultra-low sulfur diesel (ULSD) fuels. These blends were also tested for stability. The study employed accelerated tests as well as tests intended to simulate three real-world aging scenarios: (1) storage and handling, (2) vehicle fuel tank, and (3) high-temperature engine fuel system. Results were analyzed to determine whether ensuring B100 stability was adequate to ensure the stability of B5 and B20 blends. Several tests were also performed with two commercial antioxidant additives to determine whether these additives might improve stability. This report documents completion of the NREL Fiscal Year 2007 Annual Operating Plan Milestone 10.1. Illus.