Rod‐Like MnO_x Catalyst Derived from Mn‐MOF‐74 for Chlorobenzene Oxidation at Low Temperature

Abstract

In this study, a series of MnO x catalysts were prepared by pyrolysis of Mn-MOF-74 precursors. The calcination temperature had influence on the structure and catalytic performance of MnO x catalysts in the catalytic oxidation of chlorobenzene. Their physicochemical properties were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), N 2 adsorption/desorption, X-ray photoelectron spectroscopy (XPS), H 2 temperature programmed reduction (H 2 -TPR) and Fourier transform infrared (FTIR), respectively. The order of catalytic activity was as follows: rod-like MnO x -700 > rod-like MnO x -600 > boat-like MnO x -800. The MnO x -700 catalysts exhibited excellent activity for chlorobenzene (CB) decomposition, and the T 90 (temperature with CB conversion of 90 %) was 225 °C. The main reason was that MnO x -700 inherited the advantage of Mn-MOF-74 with high specific surface area, and had higher ratio of Mn 3 + / Mn 4 + (2.51) and O sur /O total (0.53). Meanwhile, the MnO x -700 can maintain over 90 % CB conversion at elevated temperature for 100 h. This work can provide an idea for the further development of high efficiency catalysts prepared via MOF-template in the CB decomposition.