- 作者: 丑凌軍、蔡迎春、張兵、牛建中、季生福、李樹本
- 作者服務機構: State Key Laboratory for Oxo Synthesis and Selective Oxidation, Lanzhou Institute of Chemical Physics, Chinese Academy of Sciences, Lanzhou 730000, P. R. China
- 中文摘要: CeO2-promoted Na-Mn-W/SiO2 catalyst has been studied for catalytic oxidation of methane in a micro-stainless-steel reactor at elevated pressure. The effect of operating conditions, such as GHSV, pressure and CH4/O2 ratio, has been investigated. 22.0% CH4 conversion with 73.8% C2-C4 selectivity (C2/C3/C4 = 3.8/1.0/3.6) was obtained at 1003 K, 1.5×105 h-1 GHSV and 1.0 Mpa. The results show: Elevated pressure disadvantages the catalytic oxidation of methane to C2-C4 hydrocarbons. Large amounts of C3 and C4 hydrocarbons are observed. The unfavorable effects of elevated pressure can be overcome by increasing GHSV; the reaction is strongly dependent on the operating conditions at elevated pressure, particularly dependent on GHSV and ratio of CH4/O2. Analyses by means of XRD, XPS and CO2-TPD show that CO2 produced from the reaction makes a weakly poisoning capacity of the catalyst; information of changeful valence on Ce and Mn was detected over the near-surface of the Ce-Na-W-Mn/SiO2 catalyst; the existence of Ce3+/Ce4+ and Mn2+/ Mn3+ ion couple supported that the reaction over the catalyst followed the Redeal-Redox mechanism. Oxidative re-coupling of C2H6 and CH4 in gas phase or over surface of catalyst produces C3 or C4 hydrocarbons.
- 英文摘要: --
- 中文關鍵字: OCM; Elevated pressure; CeO2-promoted Na-Mn-W/SiO2 catalyst; Useful hydrocarbon.
- 英文關鍵字: --