Mn3O4 derived from Mn-MOFs with hydroxyl group ligands for efficient toluene catalytic oxidation

Abstract

Mn3O4 catalysts have shown great potentials for toluene catalytic oxidation for the spinel structure and weak metal oxygen bonds. In this work, Mn3O4 and Mn2O3 catalysts were obtained by using Mn-MOFs with different ligands as precursors. It was found that the reduction of hydroxyl groups in 2,5-dihydroxyterephthalic acid was favorable for the preparation of Mn3O4 under the proper temperature range. The Mn3O4-MOF-74–300 catalyst exposed the highest Mn3+, Oads/Olatt and reducing capacity. Herein, the Mn3O4-MOFs-74–300 catalyst exhibited excellent performance for toluene oxidation, which could achieve 90% toluene conversion at 218 ℃ (toluene concentration = 1000 ppm and SV = 20000 mL·g−1·h−1). Moreover, the Mn3O4-MOFs-74–300 catalyst exhibited high stability, circulation performance and water resistance in the catalytic test.