Citric Acid Modified CuMnO/ZSM-5 as a Low-Cost and Stable Catalyst for the Efficient Decomposition of Toluene

In this work, Cu-Mn oxide catalysts supported on ZSM-5 zeolite (Cu7Mn3Ox/ZSM-5) were modified by low-cost method of acid leaching and employed for the catalytic oxidation of toluene. For investigating the effect of acid modification on catalysts deeply, the prepared materials were characterized by N-2 adsorption-desorption, XRD, SEM, H-2-TPR, XPS, NH3-TPD, Py-IR and TG. In the decomposition of toluene, the citric acid modified Cu7Mn3Ox/ZSM-5 exhibited excellent performance of toluene conversion and adsorption compared to Cu7Mn3Ox/ZSM-5. The preferable performance was associated with the improved pore structure and surface area, along with the more Mn4+ and Cu2+ species formed after citric acid modification. Significantly, citric acid modified Cu7Mn3Ox/ZSM-5 exhibited satisfied hydrothermal stability and good regeneration ability as well, which would offer an economical strategy to prepare effective catalysts for VOCs treatment.