Supercritical methanol (SCM) is a method of transesterification reaction without the presence of catalyst in the process. In
this method the temperature and pressure of the reactants reach up to the critical temperature and pressure of alcohol (239 ◦C and 8.1 MPa for methanol). In these conditions the solubility parameter of alcohol is reduced to a value near to triglycerides which leads to formation of a single phase solution [10]. In addition, absence of catalyst in the process, leads to simpler separation and purification steps of biodiesel.