Refining technologies for the purification of crude biodiesel

In biodiesel production, downstream purification is an important step in the overall process. This article is a critical review of the most recent research findings pertaining to biodiesel refining technologies. Both conventional refining technologies and the most recent biodiesel membrane refining technology are reviewed. The results obtained through membrane purification showed some promise in term of biodiesel yield and quality. Also, membranes presented low water consumption and less wastewater discharges. Therefore, exploration and exploitation of membrane technology to purify crude biodiesel is necessary. Furthermore, the success of membrane technology in the purification of crude biodiesel could serve as a boost to both researchers and industries in an effort to achieve high purity and quality biodiesel fuel capable of replacing non-renewable fossil fuel, for wide range of applications.

► We critically reviewed research findings pertaining to different techniques for the purification of crude biodiesel.
► Purification of crude of biodiesel using wet washing could lead to significant wastewater discharges.
► Crude biodiesel purification using dry washing technique is waterless but the adsorbents are not regenerated.
► Refining of crude biodiesel via membranes provide high-quality finished products.
► Membrane biodiesel purification is less energy consuming and generates almost zero wastewater.