An alternative, catalyst free method for transesterification uses supercritical methanol at high temperatures and pressures in a continuous process. In the supercritical state, the oil and methanol are in a singe phase, and reaction occurs spontaneously and rapidly. [1] The process can tolerate water in the feedstock, free fatty acids are converted to methyl esters instead of soap, and the catalyst removal step is eliminated. [2] The high temperatures and pressures required add to the capital cost of the plant, but energy costs of production are similar or slightly less than catalytic production routes. [3]
references
edit- ^ Bunkyakiat, Kunchana (2006). "Continuous Production of Biodiesel via Transesterification from Vegetable Oils in Supercritical Methanol". Energy and Fuels. 20. American Chemical Society: 812–817. Retrieved 2007-12-20.
{{cite journal}}: Unknown parameter|coauthors=ignored (|author=suggested) (help) - ^ Vera, C.R. (2005-8-14). "Production of biodiesel by a two-step supercritical reaction process with adsorption refining" (PDF). 2nd Mercosur Congress on Chemical Engineering, 4th Mercosur Congress on Process Systems Engineering. Rio de Janeiro. Retrieved 2007-12-20.
{{cite conference}}: Check date values in:|date=(help); Unknown parameter|booktitle=ignored (|book-title=suggested) (help); Unknown parameter|coauthors=ignored (|author=suggested) (help) - ^ Kusdiana, Dadan. "Biodiesel fuel for diesel fuel substitute prepared by a catalyst free supercritical methanol" (PDF). Retrieved 2007-12-20.
{{cite web}}: Unknown parameter|coauthors=ignored (|author=suggested) (help)