Please use this identifier to cite or link to this item:
|Type:||Artigo de periódico|
|Title:||Palladium, Palladium-tin, And Palladium-silver Catalysts In The Selective Hydrogenation Of Hexadienes: Tpr, Mössbauer, And Infrared Studies Of Adsorbed Co|
De Jesus Mendes M.
|Abstract:||Alumina-supported Pd-Sn catalysts prepared by successive impregnation of the precursors, calcination, and reduction contain SnO 2 and SnAl 2O 5, Pd-Sn solid solutions, and intermetallic phases Pd 2Sn and Pd 3Sn. The formation of Pd 3Sn is favored not only by lowering the Sn/Pd ratio but also by introducing tin through ethanolic impregnation. The dilution of surface Pd atoms is confirmed by infrared spectroscopy of adsorbed CO: when the Sn/Pd ratio increases, the linear/bridged intensity ratio increases and the dipole-dipole interactions decrease. TPR experiments show the influence of the support acidity and of the preparation procedure on the reducibility of the various Pd-Sn and Pd-Ag species; in the case of Pd-Ag catalysts, the presence of silver postpones the reduction of PdO in calcined samples. © 2000 Academic Press.|
|Appears in Collections:||Unicamp - Artigos e Outros Documentos|
Items in DSpace are protected by copyright, with all rights reserved, unless otherwise indicated.