Comparative Study of Quick Lime and CaO as Catalysts of Safflower Oil Transesterification

Abstract

This work aimed to contrast the performance of quicklime and CaO reagent grade as heterogeneous catalysts for the safflower oil transesterification reaction. Quicklime was characterized by TGA analysis, XRD, atomic absorption, nitrogen physisorption and by Hammett method. In the safflower transesterification reaction, four main variables were studied: addition reagents order, reagents dosage, type of catalyst and methanol-oil molar ratio. The addition reagents order was not found to be determinant on time for reaching equilibrium or maximum methyl esters yield. On the contrary, reagents dosage was found to negatively affect reaction rate and methyl esters yield. It was found that quicklime performs better than CaO and this was ascribed to an increased basicity found in the former. From the results can also be inferred that the use of quicklime as catalyst of the transesterification reaction allows the decrease of the process cost by reducing both, the reaction time and the required amount of alcohol.