Catalytic activity and stability of porous Co–Cu–Mn mixed oxide modified microfibrous-structured ZSM-5 membrane/PSSF catalyst for VOCs oxidation

Abstract

A porous cobalt–copper–manganese mixed oxide modified microfibrous-structured ZSM-5 membrane/PSSF (paper-like sintered stainless steel fibers) catalyst was fabricated by the incipient wetness impregnating method. Catalytic oxidation performances of VOCs in single component (isopropanol or ethyl acetate) and in binary mixtures (isopropanol and toluene, ethyl acetate and toluene) were investigated over the microfibrous-structured ZSM-5 membrane/PSSF catalyst. The stability and durability of the microfibrous-structured ZSM-5 membrane/PSSF catalyst for isopropanol oxidation were also evaluated. The as-synthesized and tested (after being used at 260 °C for 550 h) microfibrous-structured ZSM-5 membrane catalysts have been characterized by a series of techniques including SEM, EDS mapping, XRD, N₂ adsorption–desorption, XPS and H₂-TPR methods. Experimental results indicated that the total destruction of isopropanol or ethyl acetate alone over the microfibrous-structured ZSM-5 membrane/PSSF catalysts can be achieved at a temperature of 280 °C In the case of binary mixtures, the total conversion temperatures for toluene are above 300 °C The porous microfibrous-structured ZSM-5 membrane/PSSF catalyst possesses excellent reaction stability, demonstrating by a high catalytic activity (>90%) during the 550 h long-term catalytic oxidation reaction of isopropanol. After being used at 260 °C for 550 h, the structural and textural properties of the catalyst were changed slightly during the long-term catalytic oxidation process.