The reoxidation of γ-bismuth molybdate following reduction by propylene at elevated temperatures was examined using a TAP reactor. Use of the TAP reactor permitted examination of the catalyst surface at the earliest stages of reaction involving less than 1/100th of the surface. Pulsing of oxygen over the reduced catalyst at high (840 torr) and low (6 × 10−7 torr) total pressures yielded kinetic information on the reoxidation rates as functions of oxygen partial pressures, oxygen vacancies and temperature. In both pressure regimes, the reoxidation was found to be first order in both oxygen and in oxygen vacancies created during the propylene reduction. At high pressures, the reoxidation activation energy was found to be 3.4 kcal/mol while at low pressures it was measured as 5.0 to 8.7 kcal/mol.
All Science Journal Classification (ASJC) codes
- Condensed Matter Physics
- Physical and Theoretical Chemistry
- Surfaces, Coatings and Films
- Materials Chemistry