What is Biodiesel?
Biodiesel is a domestic, renewable fuel for diesel engines. Made from agricultural co-products and byproducts such as soybean oil, other natural oils, and greases, it is an advanced biofuel. To be called biodiesel, it must meet the strict quality specifications of ASTM D 6751. Biodiesel can be used in any blend with petroleum diesel fuel.
Technical Definition for Biodiesel (ASTM D 6751) and Biodiesel Blend:
Biodiesel, n - a fuel comprised of mono-alkyl esters of long chain fatty acids derived from vegetable oils or animal fats, designated B100, and meeting the requirements of ASTM D 6751.
Biodiesel Blend, n - a blend of biodiesel fuel meeting ASTM D 6751 with petroleum-based diesel fuel, designated BXX, where XX represents the volume percentage of biodiesel fuel in the blend.
How is biodiesel made?
Biodiesel is made through a chemical process called transesterification whereby the glycerin is separated from the fat or vegetable oil. The process leaves behind two products -- methyl esters (the chemical name for biodiesel) and glycerin (a valuable byproduct usually sold to be used in soaps and other products).