Published October 2009
Biodiesel is the methyl ester of fatty acids (FAME) derived from renewable resources such as virgin vegetable oil, animal fats and used cooking oil. This biofuel can be blended with or used as a replacement for petroleum-based diesel in compression ignition engines with minimal modifications.
Governments have encouraged the use of biodiesel through a series of mandates and tax incentives. In the period between 2002 through 2007 the annual growth rate in world production capacity of biodiesel exceeded 50%. In 2008 there were 699 biodiesel manufacturing facilities with a total world biodiesel capacity estimated at 33.2 million metric tons.
The majority of the biodiesel production facilities utilize a homogeneous alkaline catalyst, either sodium hydroxide or sodium methoxide. Axens has commercialized a process for the production of biodiesel via heterogeneous catalysis at elevated temperatures and pressures.
In this review we analyze the technical and economics aspects for the production of 441 million lb/yr (200,000 t/yr) of "biodiesel" using heterogeneous catalysis technology licensed by Catilin LLC. This process operates at pressures and temperatures similar to the conventional homogeneous catalysis process (ambient pressure and 60-65°C).