Biodiesel Purification via Ultrasonic-Assisted Solvent-Aided Crystallization

Wet washing is a widely used method for biodiesel purification. However, this technique generates large amount of wastewater that needs to be treated afterward, which costly and time-consuming. Thus, solvent-aided crystallization (SAC) with ultrasonic irradiation as solution movement assistance was introduced. This based on the addition 1-butanol enhance purification via crystallization. During crystallization, two phases are formed, where glycerol solidifies (solid phase) pure remains (liquid phase). Technically, implementation technology can optimize laboratory work by saving time, no cleaning or propeller needed. Biodiesel purity analyzed using gas chromatography-mass spectroscopy (GC-MS), 99% achieved. The optimum parameters in achieving higher fatty acid methyl ester (FAME) were concentration 1 wt.%, coolant temperature 9 °C, time 40 min.