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Extraction of Lignin with High β-O-4 Content by Mild Ethanol Extraction and Its Effect on the Depolymerization Yield
Published on: January 7, 2019
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Monómeros aromáticos por conversión in situ de intermedios reactivos en la despolimerización catalizada por ácido de
Peter J Deuss1, Martin Scott1, Fanny Tran2
1†Stratingh Institute for Chemistry, University of Groningen, Nijenborgh 4, 9747 AG, Groningen, The Netherlands.
Journal of the American Chemical Society
|May 23, 2015
Resumen
Las nuevas estrategias convierten la lignina en valiosos productos químicos aromáticos al prevenir la recondensación de fragmentos. Este método suprime eficazmente las reacciones secundarias, produciendo diversos compuestos aromáticos como los acetalos y los aromáticos alquilo de la lignina.
Área de la Ciencia:
- Ingeniería Química Ingeniería Química.
- Química orgánica es la química orgánica.
- Conversión de la conversión de la biomasa.
Sus antecedentes:
- La conversión de lignina en productos químicos aromáticos es deseable, pero es un desafío debido a la recondensación de fragmentos.
- La acidólisis de la lignina a menudo conduce a reacciones secundarias no deseadas y bajos rendimientos de compuestos objetivo.
Objetivo del estudio:
- Desarrollar nuevas estrategias para suprimir la recondensación durante la conversión de la lignina.
- Para lograr altos rendimientos de diversos compuestos aromáticos de la lignina.
Principales métodos:
- Utilizando una cantidad catalítica de ácido trifílico para una eficiente escisión del enlace β-O-4 en la lignina.
- Captura de intermediarios reactivos de aldehído a través de la reacción con diolos, hidrogenación in situ o descarbonización.
Principales resultados:
- Se han producido con éxito acetalos, aromáticos de etanol/etil y aromáticos de metilo en altos rendimientos.
- Aplicabilidad demostrada del método a la materia prima real de lignina.
- Suprimía significativamente la formación de productos secundarios de alto peso molecular.
Conclusiones:
- Las estrategias desarrolladas evitan efectivamente la recondensación mediada por aldehído durante la conversión de la lignina.
- Este enfoque ofrece una vía versátil para producir valiosos productos químicos aromáticos a partir de la lignina.
- El método tiene potencial para una amplia aplicación en la valorización de la lignina.
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