Biodiesel Conversion via Thermal Assisted in-Situ Transesterification of Bovine Fat Using Dimethyl Carbonate as an Acyl Acceptor

This study experimentally evidenced that bovine fat could be directly converted into fatty acid methyl esters (FAMEs) without lipid extraction step via thermally assisted in-situ transesterification on a porous material such as SiO₂ since providing thermal energy from an external heating source drove pseudocatalytic mechanisms caused by mobility difference between lipid in bovine fat and acyl acceptor. In particular, this study employed dimethyl carbonate (DMC) as an acyl acceptor due to its nontoxicity and economic viability. In order to validate thermal assisted in-situ transesterification, thermal degradation of bovine fat was characterized, which revealed that thermal behavior of lipid in bovine fat was nearly identical to refined lipid. The results also evidenced that bovine fat contains 12.51 wt % impurities. Fatty acid profiles were identical under different transesterification conditions, which provide evidence that the thermal assisted in-situ transesterification should be technically feasible. In order to find an optimal reaction condition, in-situ transesterification of bovine fat was tested between 340 and 390 °C; the maximum conversion of bovine fat was achieved at 380 °C. This study reported optimal conditions for thermal assisted in-situ transesterification of bovine fat, and 96.1% FAME yield from bovine fat was achieved at 380 °C.