The transesterification process will be adopted for the
preparation of ethyl ester or methyl ester of Castor
(Ricinus communis) oil. In the preparation of ethyl ester
(biodiesel), five distinct stages will be involved,
1) Heating of oil.
2) Preparation of alkaline mixture.
3) Adding of alkaline alcohol to oil and stirring the
mixture.
4) Settling of separation of glycerol.
5) Washing of ethyl ester with water.
The biodiesel can be obtained by transesterification of
castor oil using either ethanol or methanol as the Transesterification
agent. The extraction of biodiesel from castor
oil, in the presence of the catalysts faster with methanol
as the transesterification agent compared with ethanol.
The maximum yield of esters depends on the reaction
time and that is 1 hour with methanol or of 5 hours with
ethanol. However, while similar yields of fatty acid esters
may be obtained following ethanolysis or methanolysis,
the reaction times required to attain them are
very different, with methanolysis being much more rapid
[16]. The transesterification of castor oil via ethanolysis
or methanolysis can be improved through the development
of more efficient catalytic systems and processes, to
maintain kinetic control of the reaction, and by optimization
of purification procedures.