Ceria applications

J.C. Serrano-Ruiz, A. Sepulveda-Escribano, F. Rodriguez-Reinoso, Bimetallic PtSn/C catalysts promoted by ceria application in the nonoxidative dehydrogenation of isobutene. J. Catel. 246, 158-165 (2007)... 

P. P. Dholabhai, S. Anwar, J. B. Adams, P. Crozier, and R. Sharma, J. Solid State Chem., 184, 811 (2011). Kinetic Lattice Monte Carlo Model for Oxygen Vacancy Diffusion in Praseodymium Doped Ceria Applications to Materials Design. 

Cerium oxides are outstanding oxide materials for catalytic purposes, and they are used in many catalytic applications, for example, for the oxidation of CO, the removal of SOx from fluid catalytic cracking flue gases, the water gas shift reaction, or in the oxidative coupling reaction of methane [155, 156]. Ceria is also widely used as an active component in the three-way catalyst for automotive exhaust pollution control,... 

Colina JZ, Nix RM, Weiss H (2005) Growth, structure, and stability of ceria films on Si (111) and the application of CaF2 buffer layers. J Phys Chem B 109 10978-10985... 

Jacobs, G., Williams, L., Graham, U., Sparks, D., Thomas, G., and Davis, B.H. 2003. Low temperature water-gas shift In situ DRIFTS-reaction study of ceria surface area on the evolution of formates on Pt/Ce02 fuel processing catalysts for fuel cell applications. Appl. Catal. A Gen. 252 107. 

The application of the SEA approach to other systems is straightforward, and involves the three steps (PZC determination, uptake-pH survey, and tuned reduction) demonstrated in the earlier sections. It has recently been suggested that electrostatic adsorption over silanol groups is the cause for metal overexchange in low-aluminum zeohtes [61], It is presently being employed to study noble metal uptake on pure oxides of titania, ceria, zirconia, and niobia. 

A key factor in the possible applications of oxide ion conductors is that, for use as an electrolyte, their electronic transport number should be as low as possible. While the stabilised zirconias have an oxide ion transport number of unity in a wide range of atmospheres and oxygen partial pressures, the BijOj-based materials are easily reduced at low oxygen partial pressures. This leads to the generation of electrons, from the reaction 20 Oj + 4e, and hence to a significant electronic transport number. Thus, although BijOj-based materials are the best oxide ion conductors, they cannot be used as the solid electrolyte in, for example, fuel cell or sensor applications. Similar, but less marked, effects occur with ceria-based materials, due to the tendency of Ce ions to become reduced to Ce +. 

Catalysts. - Group VIII metals, conventional base metal catalysts (Ni, Co, and Fe) as well as noble metal catalysts (Pt, Ru, Rh, Pd) are active for the SR reaction. These are usually dispersed on various oxide supports. y-Alumina is widely used but a-alumina, magnesium aluminate, calcium aluminate, ceria, magnesia, pervoskites, and zirconia are also used as support materials. The following sections discuss the base metal and noble metal catalysts in detail, focusing on liquid hydrocarbon SR for fuel cell applications. 

Conventional Ni-based catalysts still dominate in SR applications however, ceria-supported noble metal catalysts have also attracted interest reeently. The study of Rh for both POX and ATR has increased sinee Rh is in general more active for reforming and is less prone to form carbon. H2 and CO selectivities in Rh-based catalysts have been shown to be affected by catalyst geometry. This indicates that feed mixing and mass transfer can play an important role. 

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