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Control de las vías de reacción de la hidroformilación del etileno utilizando sitios de cobalto y rodio bimetales
Yong Yuan1, Tianyou Mou1, Sooyeon Hwang2
1Chemistry Division, Brookhaven National Laboratory, Upton, New York 11973, United States.
Journal of the American Chemical Society
|March 29, 2025
Resumen
Este estudio introduce sitios aislados de cobalto de rodio en la zeolita ZSM-5 para una hidroformilación eficiente del etileno. La coordinación óptima entre el rodio y el cobalto (CN 3) aumenta significativamente las velocidades catalíticas y la selectividad para la producción de oxigenados C3.
Área de la Ciencia:
- Catálisis heterogénea
- Ciencias de los materiales
- Ingeniería química
Sus antecedentes:
- La hidroformilación del etileno es crucial para la producción de oxigenados C3.
- El desarrollo de catalizadores heterogéneos eficientes y libres de ligandos sigue siendo un reto.
- Los catalizadores existentes a menudo sufren de baja actividad y selectividad.
Objetivo del estudio:
- Para diseñar sitios aislados de cobalto de rodio (Rh-Co) dentro de la zeolita ZSM-5.
- Mejorar la actividad catalítica y la selectividad para la hidroformilación del etileno.
- Para mantener la estabilidad del catalizador en condiciones de reacción.
Principales métodos:
- Síntesis de Co-ZSM-5 con diferentes proporciones de Co/Al.
- Introducción de Rh para formar grupos aislados de Rh-Co con números de coordinación sintonizables (CN).
- Caracterizaciones in situ y cálculos de la teoría funcional de la densidad (DFT).
Principales resultados:
- El ajuste de la relación Co/Al controló el tamaño de la especie Co y la posterior coordinación Rh-Co.
- Un sitio aislado de Rh1Co3 (Rh-Co CN de 3) exhibió las tasas de hidroformilación más altas.
- La coordinación óptima mejora la unión a los intermedios de reacción, mejorando el rendimiento.
Conclusiones:
- Los sitios Rh-Co aislados en ZSM-5 son efectivos para la hidroformilación de etileno libre de ligando.
- El ajuste de coordinación a través de un metal secundario (Co) es clave para controlar las vías del catalizador de un solo átomo Rh.
- Este enfoque ofrece una estrategia prometedora para diseñar catalizadores heterogéneos avanzados.
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