The aim of this paper is to discuss the main features of the temperature-programmed reduction of high-surface-area ceria in the low-temperature range (T < 900 X) with particular emphasis on the role of oxygen diffusion. By making use of a cell model for the reaction/diffusion process, it is shown that the observed kinetics is not influenced by oxygen diffusion within the lattice for the values of oxygen diffusivity available for ceria. This result enables us to develop a simple and spatially uniform kinetic model for ceria reduction. The effects of sintering and surface area are also briefly addressed.
Some insight into the effects of oxygen diffusion in the reduction kinetics of ceria / Francesca, Giordano; Alessandro, Trovarelli; C., De Leitemburg; Giuliano, Dolcetti; Giona, Massimiliano. - In: INDUSTRIAL & ENGINEERING CHEMISTRY RESEARCH. - ISSN 0888-5885. - 40:22(2001), pp. 4828-4835. [10.1021/ie010105q]
Some insight into the effects of oxygen diffusion in the reduction kinetics of ceria
GIONA, Massimiliano
2001
Abstract
The aim of this paper is to discuss the main features of the temperature-programmed reduction of high-surface-area ceria in the low-temperature range (T < 900 X) with particular emphasis on the role of oxygen diffusion. By making use of a cell model for the reaction/diffusion process, it is shown that the observed kinetics is not influenced by oxygen diffusion within the lattice for the values of oxygen diffusivity available for ceria. This result enables us to develop a simple and spatially uniform kinetic model for ceria reduction. The effects of sintering and surface area are also briefly addressed.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
