Enhancing the performance of a PtPd/HY catalyst for HDPE/VGO hydrocracking through zeolite desilication

The valorization of post-consumer waste plastic in a refinery is an attractive initiative to avoid environmental problems caused by the poor plastic waste management. The modification of a bifunctional PtPd/HY catalyst through desilication (using NaOH) of the ultrastable HY zeolite has been carried...

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Detalles Bibliográficos
Autores: Vela Díaz, Francisco Javier, Palos Urrutia, Roberto, García, Juan Rafael, Sedran, Ulises, Bilbao Elorriaga, Javier, Arandes Esteban, José María, Gutiérrez Lorenzo, Alazne
Tipo de recurso: artículo
Fecha de publicación:2022
País:España
Institución:Universidad del País Vasco
Repositorio:Addi. Archivo Digital para la Docencia y la Investigación
OAI Identifier:oai:addi.ehu.eus:10810/59367
Acceso en línea:http://hdl.handle.net/10810/59367
Access Level:acceso abierto
Palabra clave:hydrocracking
fuels
wste plastic
waste refinery
desilication
hierarchical structure
Descripción
Sumario:The valorization of post-consumer waste plastic in a refinery is an attractive initiative to avoid environmental problems caused by the poor plastic waste management. The modification of a bifunctional PtPd/HY catalyst through desilication (using NaOH) of the ultrastable HY zeolite has been carried out to upgrade waste plastic (high-density polyethylene (HDPE)) dissolved in a secondary refinery stream (vacuum gas oil (VGO)) through hydrocracking. Three different catalysts have been studied: the parent (Cat-A), undergoing a desilication cycle (Cat-B), and subjected to two cycles of desilication (Cat-C). The characterization techniques employed have been: N2 adsorption-desorption, TEM, ICP-AES, tert-butylamine-TPD, pyridine FTIR, WDXRF, XRD and TPO. The hy-drocracking tests have been carried out in a semi-batch reactor at: 440 C; 80 bar; catalyst to feed ratio, 0.1 g(cat) (g(feed))(-1); HDPE to feed ratio, 0.2 gHDPE (g(feed))(-1); and reaction time, 2 h. The products have been fractioned ac-cording to their boiling point range in: gas, naphtha, light cycle oil, heavy cycle oil and coke. The composition of each fraction has been determined in terms of concentration of paraffins, olefins, naphthenes and (mono-, di-and poly-) aromatics. The results show that alkaline treated catalysts enhance the fuel production, with high HDPE and HCO conversions. The Cat-C (the one submitted to two desilication cycles) has displayed the greatest per-formance, reducing by half the gas yield and increasing the naphtha yield by 51 wt% respect to those obtained with the parent catalyst (Cat-A). Moreover, it has decreased the coke deposition and the coke formed has been less developed.