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Catalizador multifuncional de WO3-ZrO2 con soporte de platino para la hidrogenización notablemente eficiente de los
Kang Yuan1, Yukari Yamazaki1, Xiongjie Jin1
1Department of Chemistry and Biotechnology, Graduate School of Engineering, The University of Tokyo, Bunkyo-ku, Tokyo 113-8656, Japan.
Journal of the American Chemical Society
|January 19, 2023
Resumen
Un nuevo catalizador de platino en soportes de tungsteno y óxido de zirconio permite la hidrogenólisis de ésteres a alcanos en condiciones suaves. Este proceso eficiente convierte los aceites renovables en combustibles de hidrocarburos a bajas temperaturas y presión ambiente.
Área de la Ciencia:
- Catálisis
- Química ecológica
- Energía renovable
Sus antecedentes:
- La hidrogenolización de ésteres a alcanos es vital para la producción de combustibles de hidrocarburos a partir de aceites vegetales.
- Los métodos actuales a menudo requieren condiciones duras, lo que limita la eficiencia energética.
- El desarrollo de protocolos suaves y energéticamente eficientes es un desafío importante.
Objetivo del estudio:
- Desarrollar un catalizador robusto para una hidrogenólisis eficiente de ésteres en condiciones suaves.
- Permitir la síntesis de combustibles de hidrocarburos a partir de materias primas renovables a bajas temperaturas y bajo presión ambiente.
Principales métodos:
- Síntesis de un catalizador de platino apoyado en tungsteno y óxido de zirconio (Pt/WO3-ZrO2).
- Prueba del catalizador para la hidrogenólisis de ésteres a bajas temperaturas (hasta 70 °C) y a presión de H2 ambiente.
- Investigación de la reutilización del catalizador y realización de estudios mecanicistas.
Principales resultados:
- El catalizador Pt/WO3-ZrO2 logró una alta actividad y selectividad (>95%) para la conversión de éster en alcano a temperaturas suaves.
- Se observó una conversión completa de tristearina en alcanos a 130 °C sin pérdida de carbono.
- El catalizador demostró una excelente reutilización sin una pérdida significativa de rendimiento.
- Los estudios mecanicistas indicaron la importancia de las propiedades ácidas y redox del soporte.
Conclusiones:
- Se desarrolló un catalizador heterogéneo altamente activo y reutilizable (Pt/WO3-ZrO2) para la hidrogenólisis de ésteres.
- El catalizador permite la producción energéticamente eficiente de combustibles de hidrocarburos a partir de fuentes renovables bajo condiciones suaves.
- El soporte multifuncional WO3-ZrO2 es crucial para el rendimiento superior del catalizador.
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