FATTY METHYL ESTERS FROM VEGETABLE OILS FOR USE AS A DIESEL FUEL

The world is confronted with the twin crisis of fossil fuel depletion and environmental degradation. The indiscriminate extraction and consumption of Fossil fuels have led to a reduction in petroleum. Due to the concern on the availability of recoverable fossil fuel reserves and environmental problems caused by the use of those fossil fuels, considerable attention has been given to biodiesel production. The methyl esters of vegetable oils, known as biodiesel becoming increasing popular, because of its potential as a green alternative fuel for diesel fuel. It has many advantages over conventional diesel fuels. These include biodegradable, non toxic, nil sulfur content, reduced aromatics. It can either be directly used in engine or can be blended with conventional diesel, and requires no engine modification. There are various methods available for the production of biodiesel such as micro emulsification, dilution, pyrolysis, transesterification and esterification, among which transesterification is the best process. Biodiesel is produced by transesterifying the parent oil or fat with an alcohol, usually methanol, in presence of a catalyst usually strong base such as NaOH or KOH or, preferably an increasingly more commonly alkoxide. The transesterification reaction variable that affect yield and purity of the product include molar ratio of alcohol to vegetable oil, type of catalyst, molar ratio of catalyst to oil, temperature and degree of refinement of vegetable oil. In this paper various vegetable oils transesterification was studied with the purpose of achieving the best conditions for biodiesel production.