PARTIAL OXIDATION OF ETHANE OVER SUPPORTED VANADIUM PENTOXIDE CATALYSTS

The partial oxidation of ethane has been studied on silica-supported V2O5 catalyst in a fix-bed continuous-flow reactor at 775-823 K. The temperature-programmed reduction of V2O5 was also investigated. Using N,0 as oxidant, the main oxidation products were ethylene, acetaldehyde, CO, and CO2. Small amounts of CH4, and C3- and C4-hydrocarbons were also identified. The selectivities for ethylene and acetaldehyde at 823 K were 57.5 and 5.1%, respectively. The introduction of water increased the rate of acetaldehyde and CO formation, but decreased that of ethylene. Kinetic orders were determined for all products. The activation energies for the formation of C2H4, CH3CHO, CO, and CO2. were 47.7, 33.3, 27.9, and 21.5 kcal/mol, respectively. Using O2 as oxidant, the same products were observed, but the conversion was higher and selectivities were lower. The addition of water to the reacting mixture enhanced the selectivity toward ethylene and acetaldehyde formation. A possible mechanism for the oxidation reaction is proposed. © 1990.