A novel solid acid catalyst synthesized from ZnAl2O4 spinel and its application in the esterification of acetic acid and n-butyl alcohol

Abstract

A new spinel-style S₂O₈²⁻/ZnAl₂O₄ solid acid catalyst was prepared by sol–gel method. The catalytic performance was evaluated by the esterification of n-butyl acetate. The structure, morphology and acidity of the samples were characterized by X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FT-IR), Field emission scanning electron microscopy (FE-SEM), N₂ physisorption, X-ray photoelectron spectroscopy (XPS) and NH₃ temperature programmed desorption (NH₃-TPD). The results showed that the catalytic performances were significantly affected by the calcination temperature. S₂O₈²⁻/ZnAl₂O₄-600 exhibited the highest catalytic activity of 91.7% under the optimum reaction conditions. The characterization showed that the mesoporous structure S₂O₈²⁻/ZnAl₂O₄-600 maintained the well crystallinity of spinel as well as the spinel-style carrier in the sulfidation and recycling.