(502a) Comparative Study of Transesterification of Refined Oil Using a Batch Reactor Versus a High Shear Mixer Pilot Scale Reactor

Biodiesel was synthesized with refined soy bean, corn, and canola oil using methanol in the presence of sodium methoxide catalyst. The transesterification reaction was first studied using a 3 liter batch reactor in the laboratory. Following the reactor study a pilot scale process using a 1 gallon per minute high shear mixer reactor was designed and built to mimic transesterification conditions conducted in the laboratory.

In each reactor setting (i.e. 3 liter reactor and high shear mixer reactor), synthesized biodiesel was made in two successive steps with glycerine separation in between. A typical biodiesel synthesis process utilizes an acid to neutralize the sodium methoxide followed by water washing to clean the biodiesel before vacuum drying. Here the biodiesel was cleaned and neutralized using commercially available ion exchange resins (Amberlite BD 10 dry, Dowex DR-G8, and Purolite PD-206). For the first study (3 liter reactor), these resins were mixed in with the biodiesel for 20 minutes. The resins were separated before vacuum drying. In the case of the high shear mixer reactor, the resins were packed into a fixed bed column.

Analysis of both the crude and refined biodiesel in this study included soap content analysis, free fatty acid analysis, as well as free and total glycerine analysis. The total glycerine analysis gave an indication of how well the starting refined oil was converted into biodiesel.