Ultrasonic Assisted Synthesis and Characterization of xCuO/CeO2–γAl2O3 Nanoatalysts

Document Type: Full article

Authors

Environmental Engineering Research Center (EERC), Faculty of Chemical Engineering, Sahand University of Technology, Sahand New Town, Tabriz, Iran

Abstract

In this paper, xCuO/CeO2–γAl2O3 nano-catalysts were successfully synthesized by precipitation from an aqueous solution which modified via ultrasonic waves. For characterization of xCuO/CeO2–γAl2O3 samples N2 adsorption results showed that the BET surface area of the CuO/CeO2–γAl2O3, X-ray diffraction (XRD), scanning electron microscope (SEM) and energy dispersive X-rays (EDX dot-mapping) were used. The BET, XRD and SEM results indicate that CuO/CeO2-γAl2O3 particles are nano-structured catalysts. These catalysts (xCuO/CeO2–γAl2O3) have high specific surface area and finer particle that confirm SEM pictures. xCuO/CeO2-γAl2O3 catalysts compared to other previous synthesised catalysts for selective CO oxidation. The activity and selectivity of these catalysts obtained in the presence of rich hydrogen stream, with space velocity of 30,000 h−1 in the absence of CO2 and H2O. Results show that CuO/CeO2–γAl2O3 catalyst represents high CO conversion in low temperature (less than 120 ◦C), and selectivity of more than 63% at 100 ◦C. Also, results show that decreasing of CeO2 amount decreases selectivity of CO oxidation.

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