The concept of using vegetal oil as an engine fuel likely dates when Rudolf Diesel (1858-1913) developed the first engine to run on peanut oil, as he demonstrated at the World Exhibition in Paris in 1900. Unfortunately, R. Diesel died 1913 before his vision of a vegetable oil powered engine was fully realized.
Rudolf Diesel firmly believed the utilization of a biomass fuel to be the real future of his engine. He wanted to provide farmers the opportunity to produce their own fuel. In 1911, he said "The diesel engine can be fed with vegetable oils and would help considerably in the development of agriculture of the countries which use it".
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"The use of vegetable oils for
engine fuels may seem insignificant today. But such oils may become in
the course of time as important as the petroleum and coal tar products
of the present time" Rudolf Diesel, 1912 |
After R. Diesel death the petroleum industry was rapidly
developing and produced a cheap by-product "diesel fuel" powering a
modified "diesel-engine". Thus, clean vegetable oil was forgotten as a
renewable source of power.
Modern diesels are now designed to run on a less viscous fuel than vegetable
oil but, in times of fuel shortages, cars and trucks were successfully run
on preheated peanut oil and animal fat. It seems that the upper rate for
inclusion of rapeseed oil with diesel fuel is about 25% but crude vegetal
oil as a diesel fuel extender induces poorer cold-starting performance
compared with diesel fuel or biodiesel made with fatty esters (McDonnel K
et al. JAOCS 1999, 76, 539).
Today's diesel engines require a clean-burning, stable fuel operating under
a variety of conditions. In the mid 1970s, fuel shortages spurred interest
in diversifying fuel resources, and thus biodiesel as fatty esters was
developed as an alternative to petroleum diesel. Later, in the 1990s,
interest was rising due to the large pollution reduction benefits coming
from the use of biodiesel. The use of biodiesel is affected by legislation
and regulations in all countries (Knothe G, Inform 2002, 13, 900). On
February 9, 2004, the Government of the Philippines directed all of its
departments to incorporate one percent by volume coconut biodiesel in diesel
fuel for use in government vehicles. The EU Council of Ministers adopted new
pan-EU rules for the detaxation of biodiesel and biofuels on October 27,
2003. Large-volume production occurs mainly in
Europe, with
production there now exceeding 1.4 million tons per year. Western European
biodiesel production capacity was estimated at about 2 million metric tons
per year largely produced through the transesterification process, about
one-half thereof in Germany (440,000 and 350,000 MT in France and Italy,
respectively). In the United States, by 1995, 10 percent of all federal
vehicles were to be using alternative fuels to set an example for the
private automotive and fuel industries. Several studies are now funded to
promote the use of blends of biodiesel and heating oil in USA. In USA
soybean oil is the principal oil being utilized for biodiesel (about 80,000
tons in 2003). Details may be viewed on-line through the
National Biodiesel Board web site.
Several reviews on sources, production, composition and properties of
biodiesel may be consulted for further information:
- Bajpai D et al., J Oleo Sci 2006, 55, 487
- Ramadhas AS et al., Renewable Energy 2004, 29, 727-742
A review of the use of vegetable oils as engine fuels may be consulted (Ramadhas
AS et al. Renew Energy 2007, 29, 727).
The book of Nitske WR et al. may be consulted for the history of
biodiesel (Nitske WR, Wilson CM, Rudolf Diesel: Pioneer of the age of
power)