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Deactivation and regeneration dynamics in hierarchical zeolites: Coke characterization and impact on catalytic cracking of vacuum gas oil

Affiliations
  • 1Grupo de Investigación en Oxi/Hidrotratamiento Catalítico y Nuevos Materiales, Programa de Química-Ciencias Básicas, Universidad del Atlántico, Barranquilla, Colombia.
  • 2Grupo de Investigación Química Supramolecular Aplicada, Ciencias Básicas, Universidad del Atlántico, Puerto Colombia, Colombia.
  • 3Centro de Investigaciones en Ciencias de la Vida, Facultad de Ciencias Básicas y Biomédicas, Universidad Simón Bolívar, 080002, Barranquilla, Atlántico, Colombia.
  • 4Instituto de Investigaciones en Catálisis y Petroquímica “Ing.José M. Parera” (INCAPE)- Universidad. Nacional del Litoral, CONICET, RN 168, Km 0 Paraje El Pozo, Santa Fe, Argentina.

Published on:

September 24, 2024

Abstract

This study investigated the deactivation and regeneration of hierarchical zeolites in vacuum gas oil conversion, aiming to reach the equilibrium state seen in fluidized bed catalytic cracking (FCC). The research utilized various characterization techniques to analyze the properties of zeolites before and after coking and regeneration. Zeolite Y-0.20-S was found to have the highest gasoline selectivity and quality, mirroring industrial yields, and displayed notable stability across deactivation/regeneration cycles. Higher mesopore concentration in zeolites led to increased coke selectivity and better resistance to deactivation. The study observed a dominance of aromatic coke with a higher degree of condensation in these zeolites. Despite coke deposition affecting acid and textural properties, the regeneration process effectively restored these characteristics, proving its efficiency. The zeolites with greater mesoporosity retained their fundamental properties responsible for activity and selectivity, highlighting the importance of selecting materials that provide high conversions and maintain stability and product selectivity over multiple cycles. The Y-0.20-S zeolite, in particular, was identified as a promising candidate for commercial catalyst development for gasoline production, contributing to the FCC process’s energy efficiency.

Keywords:

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