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Reciclaje de polietileno hasta obtener alquilaromáticos de cadena larga mediante hidrogenización/aromatización en
Fan Zhang1, Manhao Zeng2, Ryan D Yappert3
1Department of Chemical Engineering, University of California, Santa Barbara, CA 93106, USA.
Science (New York, N.Y.)
|October 23, 2020
Resumen
El reciclaje químico de los residuos plásticos es posible. Los catalizadores de platino convierten el polietileno en productos valiosos de hidrocarburos como los alquilaromáticos y los alquilnaftenos, ofreciendo una solución sostenible a los residuos plásticos.
Área de la Ciencia:
- Ingeniería Química
- Ciencias de los materiales
- Catálisis
Sus antecedentes:
- Los residuos plásticos representan un desafío medioambiental importante.
- El reciclaje químico ofrece una solución potencial para la gestión de residuos plásticos.
- Las poliolefinas constituyen una gran parte de los residuos plásticos.
Objetivo del estudio:
- Investigar el reciclaje químico del polietileno en productos valiosos de hidrocarburos.
- Para explorar la conversión catalítica en tándem de las poliolefinas.
- Evaluar la viabilidad del uso de residuos plásticos como materia prima.
Principales métodos:
- Conversión catalítica en tándem con platino apoyado en γ-alumina.
- Procesamiento de varios grados de polietileno sin adición de disolvente o hidrógeno.
- La reacción se lleva a cabo a una temperatura moderada de 280°C.
Principales resultados:
- Se obtuvieron altos rendimientos (hasta un 80 por ciento en peso) de productos líquidos o de cera de bajo peso molecular.
- Los principales productos incluyen valiosos alquilaromáticos de cadena larga y alquilnaftenos (~ C30).
- Se observó una producción mínima de gases ligeros y la ausencia de disolvente/hidrógeno.
Conclusiones:
- Las poliolefinas de desecho se pueden convertir efectivamente en productos de hidrocarburos moleculares valiosos.
- El proceso catalítico en tándem es termodinámicamente accesible.
- Este enfoque presenta una vía viable para el reciclaje químico de residuos plásticos.
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