Effect of Dopants on the Properties of Zirconia‐Supported Iron Catalysts for Ethylbenzene Dehydrogenation with Carbon Dioxide

Abstract

Due to the harmful effects of carbon dioxide to the environment, a lot of work has been carried out aiming to find new applications, which can decrease the emissions or to capture and use it. An attractive application for carbon dioxide is the synthesis of chemicals, especially for producing styrene by ethylbenzene dehydrogenation, in which it increases the catalyst activity and selectivity. In order to find efficient catalysts for the reaction, the effect of cerium, chromium, aluminum, and lanthanum on the properties of zirconia-supported iron oxides was studied in this work. The modified supports were prepared by precipitation and impregnated with iron nitrate. The obtained catalysts were characterized by thermogravimetry, Fourier transform infrared spectroscopy, Xray diffraction, specific surface area measurement, and temperature-programmed reduction. The catalysts showed different textural and catalytic properties, which were associated to the different phases in the solids, such as monoclinic or tetragonal zirconia, hematite, maghemite, cubic ceria, monoclinic or hexagonal lantana, and rhombohedral chromia, the active phases in ethylbenzene dehydrogenation. The most promising dopant was cerium, which produces the most active catalyst at the lowest temperature, probably due to its ability of providing lattice oxygen, which activates carbon dioxide and increases the reaction rate.

Uso del aparato Bionator de Balters en el tratamiento de la mordida cruzada anterior en la dentición decidua: un reporte de caso

“…El análisis labial final en la Figura 19 indicó una protrusión de 2 mm en el labio superior y una protrusión de 3 mm en el labio inferior con respecto a la Línea S. Fuente: Propia (2023).…”