Enhanced epoxidation of soybean oil by novel Al 2 O 3 –ZrO 2 –TiO 2 solid acid catalyst

This study aims to develop highly efficient, recyclable solid catalysts for the epoxidation of vegetable oils. An Al 2 O 3 –ZrO 2 –TiO 2 solid acid catalyst was prepared by a co‐precipitation/impregnation method and characterised through scanning electron microscopy, energy‐dispersive spectroscopy, X‐ray diffraction, X‐ray photoelectron spectroscopy, Fourier‐transform infrared and nitrogen adsorption–desorption analyses. The solid acid catalyst with a high surface area and typical slit pore adsorption was successfully synthesised. Al 2 O 3 –ZrO 2 –TiO 2 also exhibits high stability and improved catalytic efficiency in the epoxidation of soybean oil. An oil conversion rate of 86.6%, which is higher than that of conventional catalysts, was obtained with a catalyst loading of 0.8 wt% and was maintained at 76.6% even after recycling the catalyst three times. The performance of the solid catalyst was slightly superior to that of H 2 SO 4 . Therefore, this novel catalyst may potentially be applicable in catalysing soybean oil epoxidation.