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Carbonización selectiva del metanol al ácido acético en catalizadores heterogéneos dispersos atómicamente ReO4/SiO2
Ji Qi1, Jordan Finzel1, Hossein Robatjazi1
1Department of Chemical Engineering, University of California, Santa Barbara, Santa Barbara, California 93117, United States.
Journal of the American Chemical Society
|July 22, 2020
Resumen
Este estudio introduce un nuevo catalizador heterogéneo que utiliza renio dispersado atómicamente en sílice para la carbonilación del metanol en ácido acético, logrando una alta selectividad y actividad sin haluros corrosivos.
Área de la Ciencia:
- Catálisis
- Ciencias de los materiales
- Ingeniería Química
Sus antecedentes:
- La carbonilación de metanol a ácido acético generalmente utiliza catalizadores homogéneos con promotores de haluro corrosivos.
- El desarrollo de catalizadores heterogéneos eficientes para este proceso es crucial para las aplicaciones industriales.
Objetivo del estudio:
- Desarrollar un catalizador heterogéneo sin haluros para la carbonilación del metanol en ácido acético.
- Investigar el funcionamiento y el mecanismo de las especies de óxido de renio dispersadas atómicamente en soportes de sílice.
Principales métodos:
- Síntesis de ReO4 dispersado atómicamente en SiO2 utilizando trietanolamina.
- Caracterización mediante el uso de AC-STEM, espectroscopia UV-vis y XAS.
- Mediciones de reactividad, análisis cinético, FTIR in situ y XAS in situ.
Principales resultados:
- La dispersión atómica de ReO4 en SiO2 demostró una selectividad >93% para el ácido acético con una conversión >60%.
- El catalizador mostró un rendimiento estable durante 60 horas en carbonilación de metanol en fase gaseosa.
- La adición de promotor Rh aumentó aún más la selectividad a >96%.
Conclusiones:
- El ReO4 dispersado atómicamente en SiO2 inerte representa un catalizador heterogéneo libre de haluros prometedor para la producción de ácido acético.
- El mecanismo propuesto implica la activación del metanol y la inserción de CO.
- Este trabajo abre caminos para nuevos catalizadores heterogéneos en la carbonilación de alcohol.
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