LCA studies comparing biodiesel synthesized by conventional and supercritical methanol methods

Biodiesel is one of the candidates for alternative fuels since it is renewable, sustainable and produced from domestic or non-food crop resources with less detrimental environmental impact. There are several different approaches to the production process. In this paper a new production method, the supercritical methanol process, was investigated and its environmental performance was compared with the conventional alkali-catalyzed process using LCA as a tool. The supercritical process is technically a simpler production process and offers the advantages of higher yields and the production of less environmentally damaging wastes. However, it still generates a significantly higher environmental load since the methanol recovery unit requires a large amount of energy.