States of Pt in Pt/C catalyst precursors after impregnation,drying and reduction steps

S.R DE MIGUEL; O.A. SCELZA; M.C. ROMAN-MARTINEZ; C. SALINAS-MARTINEZ DE LECEA; D. CAZORLA-AMOROS; A. LINARES-SOLANO

APPLIED CATALYSIS A-GENERAL

Elsevier

Lugar: Amsterdam; Año: 1998 vol. 170 p. 93 - 103

0926-860X

The characterization of Pt/C catalysts after impregnation and activation steps has been carried out by using different techniques: TPD; TPR; XPS; EXAFS and H2 chemisorption. Furthermore, the catalytic activity of the samples has been tested in the cyclohexane dehydrogenation. The catalysts were prepared from a puri®ed peach pit derived carbon and two H2O2- functionalized supports obtained from it. Results showed that the interaction of H2PtCl6 with the carbon implies a redox process in which after impregnation and drying steps, the metal complex is stabilized as Pt2. on the carbon surface. The functionalization treatment seems to have no effect on the resulting state of platinum. During the activation step (thermal treatment in H2), apart from the reduction of Pt species to Pt0, catalyzed and non-catalyzed reactions involving CO and CO2 functionalization treatment seems to have no effect on the resulting state of platinum. During the activation step (thermal treatment in H2), apart from the reduction of Pt species to Pt0, catalyzed and non-catalyzed reactions involving CO and CO2 process in which after impregnation and drying steps, the metal complex is stabilized as Pt2. on the carbon surface. The functionalization treatment seems to have no effect on the resulting state of platinum. During the activation step (thermal treatment in H2), apart from the reduction of Pt species to Pt0, catalyzed and non-catalyzed reactions involving CO and CO2 functionalization treatment seems to have no effect on the resulting state of platinum. During the activation step (thermal treatment in H2), apart from the reduction of Pt species to Pt0, catalyzed and non-catalyzed reactions involving CO and CO2 functionalized supports obtained from it. Results showed that the interaction of H2PtCl6 with the carbon implies a redox process in which after impregnation and drying steps, the metal complex is stabilized as Pt2. on the carbon surface. The functionalization treatment seems to have no effect on the resulting state of platinum. During the activation step (thermal treatment in H2), apart from the reduction of Pt species to Pt0, catalyzed and non-catalyzed reactions involving CO and CO2 functionalization treatment seems to have no effect on the resulting state of platinum. During the activation step (thermal treatment in H2), apart from the reduction of Pt species to Pt0, catalyzed and non-catalyzed reactions involving CO and CO2 process in which after impregnation and drying steps, the metal complex is stabilized as Pt2. on the carbon surface. The functionalization treatment seems to have no effect on the resulting state of platinum. During the activation step (thermal treatment in H2), apart from the reduction of Pt species to Pt0, catalyzed and non-catalyzed reactions involving CO and CO2 functionalization treatment seems to have no effect on the resulting state of platinum. During the activation step (thermal treatment in H2), apart from the reduction of Pt species to Pt0, catalyzed and non-catalyzed reactions involving CO and CO2 in the cyclohexane dehydrogenation. The catalysts were prepared from a puri®ed peach pit derived carbon and two H2O2- functionalized supports obtained from it. Results showed that the interaction of H2PtCl6 with the carbon implies a redox process in which after impregnation and drying steps, the metal complex is stabilized as Pt2. on the carbon surface. The functionalization treatment seems to have no effect on the resulting state of platinum. During the activation step (thermal treatment in H2), apart from the reduction of Pt species to Pt0, catalyzed and non-catalyzed reactions involving CO and CO2 functionalization treatment seems to have no effect on the resulting state of platinum. During the activation step (thermal treatment in H2), apart from the reduction of Pt species to Pt0, catalyzed and non-catalyzed reactions involving CO and CO2 process in which after impregnation and drying steps, the metal complex is stabilized as Pt2. on the carbon surface. The functionalization treatment seems to have no effect on the resulting state of platinum. During the activation step (thermal treatment in H2), apart from the reduction of Pt species to Pt0, catalyzed and non-catalyzed reactions involving CO and CO2 functionalization treatment seems to have no effect on the resulting state of platinum. During the activation step (thermal treatment in H2), apart from the reduction of Pt species to Pt0, catalyzed and non-catalyzed reactions involving CO and CO2 functionalized supports obtained from it. Results showed that the interaction of H2PtCl6 with the carbon implies a redox process in which after impregnation and drying steps, the metal complex is stabilized as Pt2. on the carbon surface. The functionalization treatment seems to have no effect on the resulting state of platinum. During the activation step (thermal treatment in H2), apart from the reduction of Pt species to Pt0, catalyzed and non-catalyzed reactions involving CO and CO2 functionalization treatment seems to have no effect on the resulting state of platinum. During the activation step (thermal treatment in H2), apart from the reduction of Pt species to Pt0, catalyzed and non-catalyzed reactions involving CO and CO2 process in which after impregnation and drying steps, the metal complex is stabilized as Pt2. on the carbon surface. The functionalization treatment seems to have no effect on the resulting state of platinum. During the activation step (thermal treatment in H2), apart from the reduction of Pt species to Pt0, catalyzed and non-catalyzed reactions involving CO and CO2 functionalization treatment seems to have no effect on the resulting state of platinum. During the activation step (thermal treatment in H2), apart from the reduction of Pt species to Pt0, catalyzed and non-catalyzed reactions involving CO and CO2 2 chemisorption. Furthermore, the catalytic activity of the samples has been tested in the cyclohexane dehydrogenation. The catalysts were prepared from a puri®ed peach pit derived carbon and two H2O2- functionalized supports obtained from it. Results showed that the interaction of H2PtCl6 with the carbon implies a redox process in which after impregnation and drying steps, the metal complex is stabilized as Pt2. on the carbon surface. The functionalization treatment seems to have no effect on the resulting state of platinum. During the activation step (thermal treatment in H2), apart from the reduction of Pt species to Pt0, catalyzed and non-catalyzed reactions involving CO and CO2 functionalization treatment seems to have no effect on the resulting state of platinum. During the activation step (thermal treatment in H2), apart from the reduction of Pt species to Pt0, catalyzed and non-catalyzed reactions involving CO and CO2 process in which after impregnation and drying steps, the metal complex is stabilized as Pt2. on the carbon surface. The functionalization treatment seems to have no effect on the resulting state of platinum. During the activation step (thermal treatment in H2), apart from the reduction of Pt species to Pt0, catalyzed and non-catalyzed reactions involving CO and CO2 functionalization treatment seems to have no effect on the resulting state of platinum. During the activation step (thermal treatment in H2), apart from the reduction of Pt species to Pt0, catalyzed and non-catalyzed reactions involving CO and CO2 functionalized supports obtained from it. Results showed that the interaction of H2PtCl6 with the carbon implies a redox process in which after impregnation and drying steps, the metal complex is stabilized as Pt2. on the carbon surface. The functionalization treatment seems to have no effect on the resulting state of platinum. During the activation step (thermal treatment in H2), apart from the reduction of Pt species to Pt0, catalyzed and non-catalyzed reactions involving CO and CO2 functionalization treatment seems to have no effect on the resulting state of platinum. During the activation step (thermal treatment in H2), apart from the reduction of Pt species to Pt0, catalyzed and non-catalyzed reactions involving CO and CO2 process in which after impregnation and drying steps, the metal complex is stabilized as Pt2. on the carbon surface. The functionalization treatment seems to have no effect on the resulting state of platinum. During the activation step (thermal treatment in H2), apart from the reduction of Pt species to Pt0, catalyzed and non-catalyzed reactions involving CO and CO2 functionalization treatment seems to have no effect on the resulting state of platinum. During the activation step (thermal treatment in H2), apart from the reduction of Pt species to Pt0, catalyzed and non-catalyzed reactions involving CO and CO2 2O2- functionalized supports obtained from it. Results showed that the interaction of H2PtCl6 with the carbon implies a redox process in which after impregnation and drying steps, the metal complex is stabilized as Pt2. on the carbon surface. The functionalization treatment seems to have no effect on the resulting state of platinum. During the activation step (thermal treatment in H2), apart from the reduction of Pt species to Pt0, catalyzed and non-catalyzed reactions involving CO and CO2 functionalization treatment seems to have no effect on the resulting state of platinum. During the activation step (thermal treatment in H2), apart from the reduction of Pt species to Pt0, catalyzed and non-catalyzed reactions involving CO and CO2 process in which after impregnation and drying steps, the metal complex is stabilized as Pt2. on the carbon surface. The functionalization treatment seems to have no effect on the resulting state of platinum. During the activation step (thermal treatment in H2), apart from the reduction of Pt species to Pt0, catalyzed and non-catalyzed reactions involving CO and CO2 functionalization treatment seems to have no effect on the resulting state of platinum. During the activation step (thermal treatment in H2), apart from the reduction of Pt species to Pt0, catalyzed and non-catalyzed reactions involving CO and CO2 2PtCl6 with the carbon implies a redox process in which after impregnation and drying steps, the metal complex is stabilized as Pt2. on the carbon surface. The functionalization treatment seems to have no effect on the resulting state of platinum. During the activation step (thermal treatment in H2), apart from the reduction of Pt species to Pt0, catalyzed and non-catalyzed reactions involving CO and CO2 functionalization treatment seems to have no effect on the resulting state of platinum. During the activation step (thermal treatment in H2), apart from the reduction of Pt species to Pt0, catalyzed and non-catalyzed reactions involving CO and CO2 2. on the carbon surface. The functionalization treatment seems to have no effect on the resulting state of platinum. During the activation step (thermal treatment in H2), apart from the reduction of Pt species to Pt0, catalyzed and non-catalyzed reactions involving CO and CO22), apart from the reduction of Pt species to Pt0, catalyzed and non-catalyzed reactions involving CO and CO2 desorbed from the carbon surface, take place. It was also found that the Pt2. species are reduced to zerovalent Pt even by thermal treatment of the dried samples with He. The electronic state of reduced platinum is not modi®ed by the differences in the support surface chemistry. thermal treatment of the dried samples with He. The electronic state of reduced platinum is not modi®ed by the differences in the support surface chemistry. 2. species are reduced to zerovalent Pt even by thermal treatment of the dried samples with He. The electronic state of reduced platinum is not modi®ed by the differences in the support surface chemistry.