The Activity and Characterization of Pd/Ce_0.5Zr_0.5O₂ Catalyst for the Reduction of NO

Abstract:

Pd catalysts and Ce_0.5Zr_0.5O₂ mixed oxides (CZ) was prepared by co-precipitation technique and their physicochemical properties were characterized by specific surface area measurements (BET), scanning electron microscope (SEM), and X-ray diffraction (XRD) techniques. CeO₂-ZrO₂ solid solutions supported with Pd are investigated as catalysts for reduction of NO. The research presented in this paper is focused on the intrinsic structure of CeO₂-ZrO₂ solid solution and catalytic behavior of NO over Pd/Ce_0.5Zr_0.5O₂ mixed oxides catalyst. The incorporation of ZrO₂ into the CeO₂ framework strongly promotes the reduction of Ce⁴⁺ in the bulk of the support. The surface area of Ce_0.5Zr_0.5O₂ was 32 m²/g after calcination in air at 1000 °C for 5 h. XRD results revealed the existence of Zr-rich phase in CZ sample. The experimental results show that the best Pd/Ce_0.5Zr_0.5O₂ catalyst yielded 97.75% NO conversion at typical reaction temperatures (280-320 C) and the high gas hourly space velocity of 15,000 h¹. The effect of the calcination temperature was also investigated, and the optimal calcination temperature was 400-500 C.

• Periodical: Advanced Materials Research (Volume 800)
• Pages: 93-97
• DOI: https://doi.org/10.4028/www.scientific.net/AMR.800.93
• Online since: September 2013
• Authors: Xue Tao Wang, Xu Bin, Shu Juan Kang, Cheng Rui Qu
• Keywords: Catalyst, Ce_0.5Zr_0.5O₂, NO Removal

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