ABSTRACT
Introduction This chapter summarizes the University of Idaho research related to biodegradability, biochemical oxygen demand (BOD5), chemical oxygen demand (COD), and toxicity of biodiesel (1-5). These studies were conducted in the mid-1990s using neat oils and biodiesel from a variety of feedstocks including soy, canola, rapeseed, and others. Both methyl and ethyl esters were included in most studies. Phillips 2-D low-sulfur diesel fuel was used as a comparison petrodiesel in all of the studies. In some studies, blends of the 2-D reference fuel with the test vegetable oil-based fuels were included as noted in each section. The fuel nomenclature is as follows: Phillips 2-D low-sulfur diesel control fuel, 2-D (petrodiesel); 100% rapeseed methyl ester, RME; 100% rapeseed ethyl ester, REE; 50% RME/50% 2-D, 50RME; 50% REE/50% 2-D, 50REE; 20% RME/80% 2-D, 20RME; 20% REE/80% 2-D, 20REE.
