Biodiesel consists of mono alkyl esters produced from vegetable oils,animal or old
cooking fats. Soy biodiesel is fuel alternative produced from soybean oil. Biodiesel contains no petroleum diesel, but it can be blended with petroleum diesel.
Since the oil embargo of 1973 by the OPEC a lot of research was done on biodiesel in various universities and government agencies in the USA. Soy biodiesel can be used in diesel engines with little or no modifications. Soy biodiesel is made through a chemical process called transesterification whereby the glycerin is separated from the soybean oil. The process gives two products: methyl esters (the chemical name for biodiesel) and glycerin (used to make soap).
Biodiesel is mainly produced and used in the USA. In 1999 about 0.5 million gallons was produced and this value increased to about 25 million gallons in 2003.
Advantages of soy biodiesel
As compared to normal diesel, soy biodiesel has following advantages:
- Biodiesel is better for the environment - Soy biodiesel is better for the environment because it is made from renewable resources and has lower emissions compared to petroleum diesel. The use of biodiesel in a conventional diesel engine results in substantial reduction of unburned hydrocarbons, carbon monoxide, and soot. The use of biodiesel does not increase the CO2 level in the atmosphere, since growing soybeans consumes also CO2. Biodiesel is also more biodegradable than conventional diesel. Studies at the University of Idaho have illustrated biodiesel degraded for 95 percent after 28 days compared to 40 percent for diesel fuel.
- Better lubricant - Lubrication tests have demonstrated the lubrication advantage of biodiesel.
The production of biodiesel demand new land or lands previously dedicated to food crops or forests. This may result in deforestation and shortage of foods. Only when marginal lands or agricultural residues are used the environmental advantages of biodiesel are maximal.