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El boro aislado en zeolita para la deshidrogenación oxidativa del propano
Hang Zhou1,2, Xianfeng Yi3,2, Yu Hui4,2
1Key Lab of Biomass Chemical Engineering of Ministry of Education, College of Chemical and Biological Engineering, Zhejiang University, Hangzhou 310027, China.
Science (New York, N.Y.)
|April 2, 2021
Resumen
El boro aislado dentro de los marcos de zeolita ofrece un catalizador altamente selectivo y duradero para la deshidrogenación oxidativa del propano (ODHP), un proceso crucial para producir propeno a partir de gas de esquisto.
Área de la Ciencia:
- Catálisis
- Ciencias de los materiales
- Ingeniería Química
Sus antecedentes:
- La deshidrogenación oxidativa del propano (ODHP) es vital para la producción de propeno a partir del gas de esquisto.
- Los catalizadores convencionales de óxido metálico sufren de sobreoxidación, produciendo CO y CO2 no deseados.
- Los catalizadores basados en boro son prometedores, y los oligómeros B-O-B a menudo se consideran los sitios activos.
Objetivo del estudio:
- Investigar la actividad catalítica y la selectividad del boro aislado dentro de un marco de zeolita para ODHP.
- Comprender el papel de las estructuras de boro aisladas en la mejora de la durabilidad y el rendimiento del catalizador.
- Identificar los sitios activos específicos responsables del proceso catalítico.
Principales métodos:
- Síntesis de zeolitas de borosilicato con especies de boro aisladas.
- Caracterización de las estructuras de boro aisladas mediante técnicas espectroscópicas.
- Evaluación del rendimiento del catalizador en la deshidrogenación oxidativa del propano en diversas condiciones.
- Prueba de durabilidad a largo plazo en una atmósfera húmeda.
Principales resultados:
- El boro aislado dentro de un marco de zeolita demostró una alta actividad y selectividad para el ODHP, superando a los catalizadores tradicionales.
- El enlace B-O-SiO impidió la lixiviación de boro, lo que condujo a una durabilidad superior en condiciones húmedas.
- Se propuso y validó un modelo de sitio activo con boro aislado con una estructura -B[OH...O(H) -Si].
- Esta estructura de boro aislada activó efectivamente los enlaces oxígeno y C-H para la reacción.
Conclusiones:
- El boro aislado en marcos de zeolita representa un sistema catalítico novedoso y muy eficaz para el ODHP.
- La estructura única del boro aislado mejora la estabilidad del catalizador y evita la desactivación.
- Este hallazgo abre nuevas vías para el diseño de catalizadores robustos y selectivos para transformaciones químicas valiosas.
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