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What is biodiesel?

Biodiesel is a liquid fuel made up of fatty acid alkyl esters, fatty acid methyl esters (FAME), or long-chain mono alkyl esters. It is produced from renewable sources such as new and used vegetable oils and animal fats and is a cleaner-burning replacement for petroleum-based diesel fuel. It is nontoxic and biodegradable. Biodiesel has physical properties similar to those of petroleum diesel:

Biodiesel's Physical Characteristics
Specific gravity0.87 to 0.89
Kinematic viscosity @ 40°C3.7 to 5.8
Cetane number46 to 70
Higher heating value (btu/lb)16,928 to 17,996
Sulfur, wt%0.0 to 0.0024
Cloud point °C-11 to 16
Pour point °C-15 to 13
Iodine number60 to 135
Lower heating value (btu/lb)15,700 to 16,735

Like petroleum diesel, biodiesel is used to fuel compression-ignition (diesel) engines. Low-level blends of biodiesel with petroleum diesel also provide benefits.