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What is Biodiesel?

Biodiesel is bio-based alternative fuel to diesel fuel made from the transesterification reaction of vegetable oil or animal fat. Although biodiesel is proven and used in diesel engines with added benefits to the engine, such as increased lubricity, there is a lingering question of whether use of biodiesel causes any engine trouble.

It has been proven that if pure biodiesel (aka B100) meets the ASTM D6751 specification, a biodiesel blend of up to 20% (aka B20)is approved by most engine manufacturers. Biodiesel can be blended and used in many different concentrations. X% of biodiesel by volume in Biodiesel-diesel mixture is called BX. A quality assurance program such as BQ9000 certifies the producer, marketer and test laboratories to enusure that B100 meets the ASTM D6751 specification. In fact, the the word biodiesel now can only be used for fuel that meets ASTM D6751.

ASTM International develops specifications for a wide variety of products, including conventional diesel fuel (ASTM D975). This specification allows for biodiesel concentrations of up to 5% (B5) to be called diesel fuel, with no separate labeling required at the pump. Low-level biodiesel blends, such as B5, are ASTM approved for safe operation in any compression-ignition engine designed to be operated on petroleum diesel. This can include light-duty and heavy-duty diesel cars and trucks, tractors, boats, and electrical generators.

The National Biodiesel Board and the University of Idaho under the Biodiesel Education Program has been actively involved in educating producers, distributors, and engine manufacturers about the importance of biodiesel meeting the quality.