Construction of highly active layered zeolite MCM-22 loading Pt catalyst for toluene deep oxidation

Abstract

Toluene, as a typical Volatile organic compound (VOC), is challenging to degrade at low temperatures due to its highly stable benzene ring. Herein, a novel layered zeolite MCM-22 loaded Pt (Pt@MCM-22) catalyst with excellent degradation performance for toluene was synthesized by one-pot method. The 0.5 %Pt@MCM-22 achieved 90 % toluene conversion at 159 °C (T90 = 159 °C), and the apparent activation energy value was only 77.2 kJ·mol−1 (Ea = 77.2 kJ·mol−1). The catalyst demonstrated outstanding long-term and cyclic stability. Moreover, high activity was maintained even after high-temperature treatment and in humid environments. In addition, the 0.5 %Pt@MCM-22 catalyst was rich in adsorbed oxygen (Oads) and possessed excellent oxygen mobility. The enrichment of Pt0 species provided a suitable active site for toluene oxidation. The catalytic oxidation of toluene was confirmed to follow the Mars-van Krevelen (MvK) mechanism by in situ diffuse reflectance infrared Fourier transform spectroscopy (in situ DRIFTS) measurements, and density functional theory (DFT) calculation implied that the hydroxyl groups on the catalyst can provide active oxygen for toluene oxidation. This work represents an innovative and efficient approach for the design and fabrication of highly active catalysts for toluene removal, providing a catalyst with excellent catalytic performance.