Recently, Environmental problems of global warming and depletion of resources etc. have become aggravated. As one of the solution, Bio Diesel Fuel (BDF) that is the alternate fuel of light oil is paid to attention. BDF is clean energy where SOx is not generated when burning because it uses botanical wasted oil where the sulfur element is not included for the raw material. However, in the method by the stir of the past it takes time to produce, mass production is difficult because the production in series is impossible, and there is a problem that costs rise more than light oil. In this research, the mixture fluid of wasted oil and the methanol that is the raw material of BDF is made for a methyl ester to react by the supersonic wave and it will produce in a short time compared with the stir method and element of obtained fuel and vehicle exhaust emission when burning with engine are evaluated.
