Biofuels & Biodiesel
Biofuels are fuels made from plant matter. Types of biofuels include
bioethanol, biodiesel, biogas. In the U.S. most gasoline is currently
being sold with 10% bioethanol due to Renewable Fuel Standards as well
as E85 which is 85% bioethanol and 15% gasoline. ISTC's studies have
mainly focused on biodiesel production as a way to either reduce waste
or mitigate food/fuel crop competition.
Biodiesel is used in diesel engines and burns cleaner (i.e.,
produces fewer emissions) than traditional petroleum diesel fuel.
Biodiesel is biodegradable, making it a remarkable alternative fuel
option in terms of both environmental protection and U.S. energy
independence.
How is Biodiesel Made?
Biodiesel is made from renewable organic resources, such as
vegetable oils, animal fats, or algal oils, all of which are
domestically available. Biodiesel is made by the transesterification
process - a chemical separation of glycerin from fatty acids, which then
bind to alcohol molecules.
Biodiesel vs. Biodiesel Blends
What is commonly referred to or sold as "biodiesel" is often a blend
of pure biodiesel and petroleum diesel (for example, B20 is 20%
biodiesel and 80% petroleum diesel). However, an American Society of
Testing and Materials (ASTM) standard does exist for biodiesel (ASTM
D6751) and, based upon that standard, only pure (100%) biodiesel should
be referred to as such. Any blend of biodiesel and petroleum diesel is
properly referred to as "biodiesel blend." For more information on the
technical definition of biodiesel and the specification for pure
biodiesel, see the National Biodiesel Board web site.
Flow diagram of the biodiesel making process.