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Deshidrogenación de ácido fórmico asistida por ácido de Lewis utilizando un catalizador de hierro apoyado en pinzas
Elizabeth A Bielinski1, Paraskevi O Lagaditis, Yuanyuan Zhang
1Department of Chemistry, Yale University , P.O. Box 208107, New Haven, Connecticut 06520, United States.
Journal of the American Chemical Society
|July 8, 2014
Resumen
Un nuevo catalizador de hierro libera eficientemente hidrógeno del ácido fórmico, logrando más de 1 millón de vueltas. Este avance ofrece una alternativa sostenible a los catalizadores de metales preciosos para el almacenamiento de hidrógeno.
Área de la Ciencia:
- La catálisis de la catálisis.
- Ciencia de los materiales Ciencia de los materiales.
- Química Sostenible y Sustentable.
Sus antecedentes:
- El ácido fórmico es un material prometedor para el almacenamiento de hidrógeno debido a su alto contenido de hidrógeno.
- Los catalizadores actuales para la deshidrogenación del ácido fórmico dependen predominantemente de metales preciosos caros.
- El desarrollo de catalizadores rentables y eficientes es crucial para el avance de las tecnologías de almacenamiento de hidrógeno.
Objetivo del estudio:
- Desarrollar un nuevo catalizador de metales no preciosos para la deshidrogenación eficiente del ácido fórmico.
- Investigar la actividad catalítica y el mecanismo de un sistema homogéneo a base de hierro.
- Para explorar el potencial de los ácidos de Lewis como co-catalizadores en esta reacción.
Principales métodos:
- Catálisis homogénea utilizando un complejo de hierro.
- Empleando un ácido de Lewis como co-catalizador.
- Caracterización del rendimiento catalítico a través de mediciones del número de facturación (TON).
Principales resultados:
- El catalizador de hierro, con un co-catalizador de ácido de Lewis, logró aproximadamente 1.000.000 de vueltas para la deshidrogenación del ácido fórmico.
- Esto representa el número de facturación más alto reportado para un catalizador de metales de transición de primera fila en esta reacción.
- Los estudios mecanicistas preliminares sugieren que el ácido de Lewis facilita la descarboxilación de un intermediario formado de hierro.
Conclusiones:
- Se ha desarrollado un catalizador de hierro homogéneo altamente activo y estable para la deshidrogenación del ácido fórmico.
- El uso de un co-catalizador de ácido de Lewis mejora significativamente la eficiencia catalítica.
- Este sistema basado en hierro presenta una alternativa rentable y sostenible a los catalizadores de metales preciosos para el almacenamiento de hidrógeno y la hidrogenación de CO2.
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