Synthesis of Ni-CeO2 catalyst for the partial oxidation of methane using RF thermal plasma

• Published in: Chinese journal of catalysis Vol. 37; no. 5; pp. 743 - 749
• Main Authors: Lee, M.Y., Nam, J.S., Seo, J.H.
• Format: Journal Article
• Language: English
• Published: Elsevier B.V 01.05.2016
• Subjects: Carbon deposition; Ceria; Methane; Nickel catalyst; Partial oxidation; RF thermal plasma; Methane; Nickel catalyst; Carbon deposition; Partial oxidation; Ceria; RF thermal plasma
• ISSN: 1872-2067; 1872-2067
• DOI: 10.1016/S1872-2067(15)61071-3

Ni-CeO2 catalysts with a nickel content of 50 mol% were prepared using RF thermal plasma, and their catalytic activities for methane partial oxidation were characterized. For the synthesis of Ni-CeO2 catalysts, a precursor containing Ni (∼5-μm diameter) and CeO2 (∼200-nm diameter) powders were heated simultaneously using an RF plasma at a power level of ∼52 kVA and a powder feeding rate of ∼120 g/h. From the X-ray diffraction data and transmission electron microscopy images, the precursor formed into high crystalline CeO2 supports with nanosized Ni particles (<–50-nm diameter) on their surfaces. The catalytic performance was evaluated under atmospheric pressure at > 500 °C and a CH4:O2 molar ratio of 2:1 with Ar diluent. Although the Ni content was high (∼50 mol%), the experimental results reveal a methane conversion rate of > 70%, selectivities of CO and H2 greater than 90% and slight carbon coking during an on-stream test at 550 °C for 24 h. However, at 750 °C, the on-stream test revealed the formation of filament-like carbons with an increased methane conversion rate over 90%. Epoxides were Ni-CeO2 nano catalyst was prepared by in-flight treatment of Ni and CeO2 powders in RF thermal plasma. The as-prepared catalyst showed high catalytic activities during the partial oxidation of methane.