Complex-Oxide Catalysts in Cracking of Propane

Abstract: The study investigates propane conversion in the presence of rare-earth metal zirconates Ln2Zr2O7 (Ln = La, Gd, and Lu) prepared by high-temperature solid-phase synthesis at 500, 1000, and 1500°C. In the La2Zr2O7 → Gd2Zr2O7 → Lu2Zr2O7 series, the phase transitions were found to follow the pyrochlore → defective fluorite → δ-phase route. This changed the parameters of the crystalline and local structures and, in particular, led to the appearance of oxygen vacancies in pyrochlore-based compounds. As a result of the structural changes, propane dehydrogenation prevailed over propane degradation. Therefore, the Lu2Zr2O7 catalyst exhibited a higher propylene selectivity (up to 65%) than La2Zr2O7, with 100% propane conversion being achieved. © Pleiades Publishing, Ltd. 2024.