The partial oxidation of ethane has been investigated on silica-supported M2MoO4 catalysts (M Li, Na, K, Rb, Cs) in a fixed-bed continuous-flow reactor at 770-823 K using N2O as oxidant. Additional measurements included pulse experiments, temperature-programmed reduction of the catalysts, and a study of the catalytic decomposition of N2O and C2H5OH. The numbers of acidic and basic sites have also been determined. Temperature-programmed reduction of the alkali metal molybdates showed that the onset temperature of the reduction decreased from Li to Cs, while the extent of the reduction increased in this sequence. The main products of the oxidation reaction were ethylene, acetaldehyde, CO, and CO2. Small amounts of CH4 and C2H5OH were also identified. The ethane conversion and the rate of the C2H4 and CH3CHO formation all increased from Li to Cs. Detailed kinetic measurements were carried out on K2MoO4/SiO2. The activation energy of the ethane consumption was 71 kJ/mol. A possible mechanism for the oxidation reaction is discussed.
ASJC Scopus subject areas
- Physical and Theoretical Chemistry