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چکیده
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To assess the synergism effect of plasma and ultrasound treatment on the physicochemical properties and catalytic performance of supported-Pt nanocatalysts, a series of nanostructured Pt(1 wt.%)/Al2O3–CeO2(30 wt.%) catalysts were prepared by plasma and/or ultrasound-assisted impregnation methods and tested for the total oxidation of toluene. The nanocatalysts were characterized by XRD, FESEM, FTIR,EDX and N2 adsorption–desorption measurements. XRD data confirmed the formation of CeO2 as the crystalline phase with an average crystallite size of about 8.7 nm for all samples. EDX dot mapping indicated homogenous dispersion of elements. The results indicated that the remarkable synergetic effect of ultrasound irradiation on the surface morphology and elemental dispersion, especially when it is coupled with plasma treatment. All treated nanocatalysts showed lower temperature activity and better catalytic performance in toluene oxidation with high stability, in particular, ultrasound–plasma assisted synthesized nanocatalyst exhibited the approximately complete oxidation of toluene at 180 C. It is observed that even at higher concentrations of toluene (3000 ppm) or GHSV, plasma–ultrasound assisted synthesized nanocatalyst had still enough destruction ability to reduce the pollutant. Therefore, the plasma–ultrasound hybrid synthesis method can lead to an excellent preparation of supported nanocatalysts, esp., those for VOCs oxidation.
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