The stoichiometry for the reaction is 3:1 M ratio of alcohol to oil, however, since the reaction is reversible, in practice, excess alcohol (6:1) is required to shift the equilibrium to the products side to raise the product yield and allow its phase separation from the glycerol to be formed [14,19].
Methanol and ethanol are used most frequently, especially methanol because of its low cost and its physical and chemical advantages (polar and shortest chain alcohol).
The presence of a catalyst considerably accelerates the adjustment of the equilibrium.