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El camino hacia la selectividad total del isómero: conversión de n-hexano (reforma) en nanopartículas de platino
Nathan Musselwhite1, Kyungsu Na, Selim Alayoglu
1Department of Chemistry, University of California, Berkeley , Berkeley, California 94720, United States.
Journal of the American Chemical Society
|November 12, 2014
Resumen
La sílice modificada con aluminio (MCF-17) combinada con nanopartículas de platino crea un catalizador altamente activo para la isomerización de n-hexano. Esta catálisis en tándem logra más del 90% de selectividad, incluso a altas temperaturas.
Área de la Ciencia:
- Ciencia de los materiales Ciencia de los materiales.
- La catálisis de la catálisis.
- Nanotecnología La nanotecnología es la nanotecnología.
Sus antecedentes:
- La sílice mesoporosa (MCF-17) es un material versátil para la catálisis.
- La modificación del aluminio introduce sitios de ácido de Lewis.
- Las nanopartículas de platino son catalizadores conocidos para las transformaciones de hidrocarburos.
Objetivo del estudio:
- Desarrollar un catalizador altamente activo y selectivo para la isomerización del n-hexano.
- Investigar el efecto sinérgico de soportes ácidos y nanopartículas metálicas.
- Para explorar el rendimiento catalítico a temperaturas elevadas.
Principales métodos:
- Síntesis de sílice mesoporosa modificada con aluminio (Al modificado MCF-17).
- Carga de nanopartículas de platino sintetizadas coloidalmente en MCF-17 y MCF-17 modificado con Al.
- Evaluación de la actividad catalítica y la selectividad para la reformación del n-hexano a 240-360 °C.
Principales resultados:
- El MCF-17 puro con modificación de aluminio no mostró actividad para la isomerización de n-hexano.
- Las nanopartículas de platino en MCF-17 tradicional exhibieron una actividad de isomerización muy baja.
- Las nanopartículas de platino en MCF-17 modificado por Al demostraron una vía de isomerización dominante con >90% de selectividad.
Conclusiones:
- Un sistema catalítico en tándem que combina MCF-17 modificado con Al ácido y nanopartículas de platino es altamente efectivo para la isomerización de n-hexano.
- La interacción sinérgica entre el soporte y las nanopartículas metálicas es crucial para una alta actividad y selectividad.
- Este sistema catalítico es prometedor para la producción eficiente de isómeros de hidrocarburos a altas temperaturas.
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