High-silica zeolite beta as a heterogeneous catalyst in transesterification of triolein for biodiesel production.

Zeolite beta with a high Si/Al ratio as a heterogeneous catalyst in the transesterification of triolein for biodiesel production was synthesized hydrothermally in fluoride media. The prepared zeolite beta was subsequently treated with dilute NaOH solutions to render better catalysis in the transesterification reaction. Effects of heating procedures, namely reflux and microwave heating, to the reaction system and sizes of the zeolite beta particles on the conversion of triolein to biodiesel were investigated as well. A conversion efficiency over 90% could be attained within an hour of the reflux reaction. Moreover, these Na-treated zeolite catalysts still exhibit acceptable endurability and good catalysis in the transesterification reaction after nine consecutive cycles. It is inferred that sodium cations existing in the cages and the defect sites of the NaOH-treated zeolite beta can be supplied to the surface of the catalysts during the transesterification reaction and, thus, to enhance the catalysis. [ABSTRACT FROM AUTHOR]