Synthesis and characterization of S2O82 −/ZnFexAl2 − xO4 solid acid catalysts for the esterification of acetic acid with n-butanol

• New spinel-types of S2O82 −/ZnFexAl2 − xO4 solid acid catalysts were prepared.
• S2O82 −/ZnFexAl2 − xO4 maintained the spinel structure as well as ZnFexAl2 − xO4.
• A certain addition of Fe played a significant effect on the acid properties.
• S2O82 −/ZnFe0.15Al1.85O4 showed the highest catalytic activity.
• S2O82 −/ZnFe0.15Al1.85O4 exhibited the excellent reusability.

New spinel-types of S2O82 −/ZnFexAl2 − xO4 solid acid catalysts were prepared by sol–gel method. Their catalytic performances for the synthesis of n-butyl acetate were investigated. The catalysts were characterized by means of XRD, IR, XPS, FT-IR of adsorbed pyridine and NH3-TPD. The experimental results showed that S2O82 −/ZnFexAl2 − xO4 solid acid catalysts maintained the spinel structure as well as the support of ZnFexAl2 − xO4. Fe3 + ions were well incorporated and highly dispersed into the spinel lattice. S2O82 −/ZnFe0.15Al1.85O4 exhibited the maximum conversion of acetic acid with 98.2%. Moreover, S2O82 −/ZnFe0.15Al1.85O4 showed better reusability, which remained above 72.7% conversion of acetic acid even after being used five times.