Preparation of solid acid catalyst SO42−/TiO2/γ-Al2O3 for esterification: A study on catalytic reaction mechanism and kinetics

In this work, a series of SO42−/TiO2/γ-Al2O3 solid acid catalysts were synthesized by impregnation method, in which nano-TiO2 was prepared by sol–gel method, and then the nano-TiO2 sol was loaded on porous γ-Al2O3 supporter through impregnation. The structure and property of catalyst were characterized by XRD, N2-BET, SEM, TEM, XPS, NH3-TPD, Pyridine-IR and FT-IR. In addition, the catalyst of chelate bidentate coordination acid center model was established. The catalytic performance test was carried out in the esterification of n-butyl alcohol with lauric acid and the catalyst showed excellent activity. The experimental results showed that the medium strength acid sites were more dominant active sites than the strong and weak acid sites for the rapid esterification reaction. Its kinetic behaviors and activation energy were studied for the esterification under the catalytic reaction condition.