Activationof Commercial CaO for Biodiesel Productionfrom Rapeseed Oil Using a Novel Deep Eutectic Solvent.

A deepeutectic solvent (DES) consisting of choline chloride andglycerol (1:2 molar ratio) was prepared and used as the solvent inCaO-catalyzed transesterification of rapeseed oil to produce biodiesel.In addition to its solvent role, DES activated commercial CaO to bea catalyst for the transesterification reaction. The yield of fattyacid methyl ester (FAME) with the addition of DES reached 91.9%, whilethe FAME yield with no DES was only 4.0%. The commercial CaO samplesbefore and after reaction were characterized by Powder X-ray diffraction(XRD), Fourier transform infrared spectroscopy (FT-IR), and ScanningElectronic Microscopy (SEM). These measurements indicate that thesurface of commercial CaO is typically covered by a layer of CaCO3and Ca(OH)2which inhibits the activity of CaO,while the addition of DES can eliminate this inhibiting layer leadingto CaO activation. [ABSTRACT FROM AUTHOR]