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Deshidrogenación selectiva del propano en propeno mediante el uso de catalizadores de nitruro de boro
J T Grant1, C A Carrero1, F Goeltl1
1Department of Chemistry, University of Wisconsin-Madison, 1101 University Avenue, Madison, WI 53706, USA.
Science (New York, N.Y.)
|December 10, 2016
Resumen
El nitruro de boro hexagonal y sus nanotubos muestran una notable selectividad para producir propeno y eteno a partir del propano. Este descubrimiento ofrece un avance potencial para la producción de olefinas, superando los desafíos anteriores de sobreoxidación.
Área de la Ciencia:
- Ingeniería Química
- Ciencias de los materiales
- Catálisis
Sus antecedentes:
- La deshidrogenación oxidativa del propano al propeno es crucial para la industria química.
- La baja selectividad al propeno, debido a la sobreoxidación al CO2, dificulta la viabilidad comercial.
- El desarrollo de nuevos catalizadores es esencial para la producción eficiente de olefinas.
Objetivo del estudio:
- Investigar las propiedades catalíticas del nitruro de boro hexagonal (h-BN) y los nanotubos de nitruro de boro (BNNT) para la deshidrogenación oxidativa del propano.
- Lograr una alta selectividad hacia las olefinas, en particular el propeno.
- Para aclarar el mecanismo de reacción e identificar los sitios catalíticos activos.
Principales métodos:
- Evaluación del rendimiento catalítico de h-BN y BNNT en la deshidrogenación oxidativa del propano.
- Análisis de los productos de reacción para determinar la selectividad y la conversión.
- Técnicas espectroscópicas y modelado ab initio para comprender el comportamiento catalítico.
Principales resultados:
- h-BN y BNNT demostraron una actividad catalítica y una selectividad sin precedentes para la producción de olefinas.
- Con una conversión de propano del 14%, se logró una selectividad del 79% para el propeno y del 12% para el eteno.
- Los bordes de los sillones terminados con oxígeno de nitruro de boro fueron identificados como los sitios activos.
Conclusiones:
- Los materiales hexagonales de nitruro de boro ofrecen una alternativa prometedora para la síntesis selectiva de olefinas.
- El mecanismo catalítico identificado proporciona una vía para el diseño de catalizadores avanzados.
- Esta investigación podría allanar el camino para una tecnología de producción de propeno comercialmente viable.
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