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Especies de tungsteno en beta zeolita con nidos abundantes de silanol para una metátesis eficiente de las olefinas

Yuehua Xiao^1,2, Yinjie Wang^1,2, Chengtao Wang^1,3,2

¹College of Chemical and Biological Engineering, State Key Laboratory of Chemical Engineering and Low-carbon Technology, Zhejiang University, Hangzhou 310058, China.

Chem & bio engineering

|September 3, 2025

Resumen

La beta-zeolita desaluminada mejora la dispersión del óxido de tungsteno (WOx), mejorando las tasas de metástasis de las olefinas. Este nuevo diseño de catalizador aumenta significativamente el rendimiento de propeno en comparación con los catalizadores tradicionales.

Área de la Ciencia:

Catálisis
Ciencias de los materiales
Ingeniería Química

Sus antecedentes:

Los catalizadores tungstate para la metatesis de olefinas presentan bajas tasas de reacción debido a la mala adsorción y activación de la olefina.
Generalmente se requieren altas temperaturas para lograr una actividad satisfactoria, lo que limita la eficiencia.

Objetivo del estudio:

Investigar el papel de los nidos de silanol en la zeolita beta desiluminada para la dispersión de óxido de tungsteno (WOx).
Mejorar la actividad y la selectividad de los catalizadores basados en tungsteno para la metástasis de olefinas.

Principales métodos:

Síntesis de las especies de óxido de tungsteno en la beta-zeolita no aluminada (DeAl-Beta) y la beta-zeolita siliciosa (Si-Beta).
Caracterización de la dispersión del catalizador y de las especies activas.
Evaluación del rendimiento catalítico en las metástasis de eteno y 1-buteno.

Principales resultados:

La beta-zeolita desiluminada (DeAl-Beta) facilitó una alta dispersión de las especies de tungsteno, formando especies activas de WOx.
El catalizador WOx/DeAl-Beta mostró un rendimiento de propeno 2,3 veces mayor que el de WOx/Si-Beta en condiciones equivalentes.
El WOx/DeAl-Beta optimizado logró un rendimiento de propeno de más del 50%, superando a los catalizadores industriales de W/SiO2.

Conclusiones:

Los nidos de silanol en la zeolita DeAl-Beta son cruciales para la alta dispersión y activación de las especies de tungsteno.
El catalizador WOx/DeAl-Beta desarrollado ofrece una alternativa prometedora para una metátesis eficiente de las olefinas.

Palabras clave:

Metátesis de las olefinas el propeno nido de silanol Óxidos de tungsteno Sector de la energía

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