Catalytic combustion of toluene over cerium modified CuMn/Al2O3/cordierite monolithic catalyst

X-ray diffraction (XRD) patterns from 5 to 85° were performed on Rigaku D/Max 2500 instrument equipped with X-ray source of Cu-Kα (λ=1.54056 Å). The N2 adsorption-desorption isotherms were obtained at 77 K using Micromeritics 3H-2000PS2. The standard Brunauer-Emmett-Teller (BET) and Barrett-Joyner-Halenda (BJH) methods to calculate the specific surface and pore size, respectively. The morphology and elemental composition of the samples were observed by scanning electron microscopy (SEM) and energy dispersive X-ray spectroscopy (EDX). X-ray photoelectron spectroscopy (XPS) experiments were operated using a ESCALAB 250 with Al Kα (hν = 1486.6 eV) excitation source. The reducibility of sample was characterized by hydrogen temperature-programmed reduction (H2-TPR). Typically, samples (150 mg) were pretreated at 300 °C for 1 h in Ar. The samples were heated from 30 °C to 900 °C in 5% H2/Ar (30 ml/min) at 10 °C/min after cooling to room temperature. For O2-TPD, 100 mg of sample was pretreated under argon at 120 °C for 60 min with a heating ramp of 10 °C/min to remove physisorbed gases and residual feed gas. After naturally cooling to room temperature, the gas was switched to 5 vol% O2/Ar and maintained 1 h. Finally, the catalyst was heated with a rate of 10 °C/min from room temperature to 900 °C.  In order to evaluate the mechanical stability of the catalyst, the adhesion of the active components of CuMnCex/Al2O3/Cor was tested by ultrasonic vibration method.