One of the environmental advantages of biodiesel is that it degrades more quickly than petro-diesel, and so does not pose a long-term harm to the environment. However, this can also be a disadvantage if the fuel degrades before it can be used. In 2006, a specification was added to ASTM 6751 (the U.S. biodiesel quality specification) in order to ensure that biodiesel has adequate protection from oxidation.
To avoid oxidation and extend the shelf life of biodiesel, commercial antioxidants can be added. The University of Idaho's biodiesel lab tested four different brands of oxidative stability additives to see how they compared in terms of effectiveness and cost.
For the results of our experiments, see the complete Tech Note at: http://www.uiweb.uidaho.edu/bioenergy/Oxidativestability.pdf
