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Synthesis of Zeolites Using the ADOR Assembly-Disassembly-Organization-Reassembly Route
Published on: April 3, 2016
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Control del interior de los poros de la zeolita para las separaciones quimioselectivas de alquinas y olefinas
Yuchao Chai1, Xue Han2, Weiyao Li2
1School of Materials Science and Engineering and National Institute for Advanced Materials, Nankai University, Tianjin 300350, China.
Science (New York, N.Y.)
|May 30, 2020
Resumen
Este estudio introduce un nuevo método que utiliza zeolitas de faujasita con soporte de níquel (Ni@FAU) para la eliminación altamente selectiva de las impurezas de alquino de las olefinas inferiores, que son cruciales para la producción de polímeros.
Área de la Ciencia:
- Ciencias de los materiales
- Catálisis
- Ciencia de la separación
Sus antecedentes:
- La eliminación eficiente de las impurezas de alquino es fundamental para la producción de olefinas inferiores de grado de polimero de alta pureza.
- Los métodos de separación existentes se enfrentan a desafíos para lograr una alta selectividad y eficiencia.
Objetivo del estudio:
- Desarrollar una nueva estrategia para controlar el interior de los poros de zeolita para mejorar la adsorción y separación de alquinos.
- Investigar el rendimiento de los sitios de níquel confinado dentro de las zeolitas de faujasita (FAU) para separar los alquinos de las olefinas.
Principales métodos:
- El confinamiento de sitios abiertos aislados de níquel (II) dentro de los anillos de seis miembros de zeolitas FAU.
- Ensayos de Ni@FAU para la adsorción y separación de mezclas de acetileno/etileno, propino/propileno y butino/1,3-butadieno.
- Utilizando la difracción de neutrones in situ y la dispersión inelástica de neutrones para dilucidar los mecanismos de unión.
Principales resultados:
- Ni@FAU ha demostrado una notable adsorción de alquinos en condiciones ambientales.
- Se han logrado selectividades de separación dinámica sin precedentes: 100 para acetileno/etileno, 92 para propino/propileno y 83 para butino/1,3-butadieno.
- Se ha identificado la unión quimioselectiva y reversible del acetileno a través de complejos metastables [Ni (II) (C2H2) ].
Conclusiones:
- El control de la química interna de los poros de zeolita a través de sitios metálicos confinados ofrece un enfoque poderoso para las separaciones industriales.
- Los adsorventes escalables basados en zeolita muestran un potencial significativo para desafiar los procesos de purificación en la industria petroquímica.
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