Metal And Precursor Effect During 1-Heptyne Selective Hydrogenation Using An Activated Carbon As Support

• Autores: Lederhos, Cecilia Rosa; Badano, Juan Manuel; Carrara, Nicolás Ricardo; Coloma Pascual, Fernando; Almansa, M. Cristina; Liprandi, Domingo Antonio; Quiroga, Monica Esther
• Año de publicación: 2013
• Idioma: inglés
• Tipo de recurso: artículo
• Materia: Activated carbon; Alkyne; Selective hydrogenation; Monometallic catalysts
• Institución: Consejo Nacional de Investigaciones Científicas y Técnicas

Palladium, platinum and ruthenium supported on activated carbon were used as catalysts for the selective hydrogenation of 1-heptyne, a terminal alkyne. All catalysts were characterized by Temperature Programmed Reduction, X-Ray Diffraction, Transmission Electron Microscopy and X-Ray Photoelectron Spectroscopy. TPR and XPS suggest that the metal in all catalysts is reduced after the pretreatment with H2 at 673 K. The TPR trace of the PdNRX catalyst shows that the support surface groups are greatly modified as a consequence of the use of HNO3 during the catalyst preparation. During the hydrogenation of 1-heptyne, both palladium catalysts were the most active and selective than the platinum and ruthenium catalysts. The activity order of the catalysts is: PdClRX > PdNRX > PtClRX >> RuClRX. This superior performance of PdClRX was attributed in part to the total occupancy of the d electronic levels of the Pd metal that is supposed to promote the rupture of the H2 bond during the hydrogenation reaction. The activity differences between PdClRX and PdNRX catalysts could be attributed to a better accessibility of the substrate to the active sites, as a consequence of steric and electronic effects of the superficial support groups. The order for the selectivity to 1-heptene is: PdClRX = PdNRX > RuClRX > PtClRX, and can be attributed mainly to thermodynamic effects.
Fil: Lederhos, Cecilia Rosa. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico - CONICET - Santa Fe. Instituto de Investigaciones en Catálisis y Petroquímica; Argentina;
Fil: Badano, Juan Manuel. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico - CONICET - Santa Fe. Instituto de Investigaciones en Catálisis y Petroquímica; Argentina;
Fil: Carrara, Nicolás Ricardo. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico - CONICET - Santa Fe. Instituto de Investigaciones en Catálisis y Petroquímica; Argentina;
Fil: Coloma Pascual, Fernando. Universidad de Alicante. Facultad de Ciencias; España;
Fil: Almansa, M. Cristina. Universidad de Alicante. Facultad de Ciencias; España;
Fil: Liprandi, Domingo Antonio. Universidad Nacional del Litoral. Facultad de Ingeniería Química. Departamento de Química; Argentina;
Fil: Quiroga, Monica Esther. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico - CONICET - Santa Fe. Instituto de Investigaciones en Catálisis y Petroquímica; Argentina; Universidad Nacional del Litoral. Facultad de Ingeniería Química. Departamento de Química; Argentina;