Preparation of CaO/KIT-6 solid base catalyst and its catalytic performance in transesterification

CaO/KIT-6 was successfully prepared by loading activated calcium oxide particles on the surface of mesoporous silica (KIT-6) by post-synthesis method and tested for the transesterification of soybean oil with methanol. The catalyst was characterized by XRD, XPS, CO₂-TPD, N₂ adsorption-desorption and TEM. It is found that when the molar ratio of methanol to oil is 12, the reaction temperature is 65 °C, the addition of catalyst is 8% and the Ca/Si atomic ratio is 0.4, the conversion of soybean oil exceeds 99.9% at 2 h. After 5 cycles, the catalytic activity decreases slightly and the conversion is still up to 90%. Compared with CaO and other supported catalysts, CaO/KIT-6 catalyst exhibits higher catalytic performance and good reusability at lower methanol-to-oil molar ratio.