A Model of Catalytic Cracking: Product Distribution and Catalyst Deactivation Depending on Saturates, Aromatics and Resins Content in Feed

The problems of catalyst deactivation and optimization of the mixed feedstock become more relevant when the residues are involved as a catalytic cracking feedstock. Through numerical and experimental studies of catalytic cracking, we optimized the composition of the mixed feedstock in order to minimize the catalyst deactivation by coke. A pure vacuum gasoil increases the yields of the wet gas and the gasoline (56.1 and 24.9 wt%). An increase in the ratio of residues up to 50% reduces the gasoline yield due to the catalyst deactivation by 19.9%. However, this provides a rise in the RON of gasoline and the light gasoil yield by 1.9 units and 1.7 wt% Moreover, the ratio of residue may be less than 50%, since the conversion is limited by the regenerator coke burning ability.

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Correlating the Process Variables and Products Involved in the Fluid Catalytic Cracking of Waste Feeds

10.20944/preprints201810.0370.v1 ◽

2018 ◽

Author(s):

José Ignacio Alvira ◽

Idoia Hita ◽

Elena Rodriguez ◽

Jose M Arandes ◽

Pedro Castaño

Keyword(s):

Catalytic Cracking ◽

Principal Component ◽

Product Distribution ◽

Vacuum Gasoil ◽

Fluid Catalytic Cracking ◽

Pyrolysis Oil ◽

Scrap Tire ◽

Feed Composition ◽

Operational Conditions ◽

Main Components

Associating the most influential parameters with the product distribution is of uttermost importance in complex catalytic processes such as fluid catalytic cracking (FCC). These correlations can lead to the information-driven catalyst screening, kinetic modeling and reactor design. In this work, a dataset of 104 uncorrelated experiments, with 64 variables, has been obtained in an FCC simulator using 6 types of feedstock (vacuum gasoil, polyethylene pyrolysis waxes, scrap tire pyrolysis oil, dissolved polyethylene and blends of the previous), 36 possible sets of conditions (varying contact time, temperature and catalyst/oil ratio) and 3 industrial catalysts. Principal component analysis (PCA) has been applied over the dataset, showing that the main components are associated with feed composition (27.41% variance); operational conditions (19.09%) and catalyst properties (12.72%). The variables of each component have been correlated with the indexes and yields of the products: conversion, octane number, aromatics, olefins (propylene) or coke, among others.

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Life and death of a single catalytic cracking particle

Science Advances ◽

10.1126/sciadv.1400199 ◽

2015 ◽

Vol 1 (3) ◽

pp. e1400199 ◽

Cited By ~ 58

Author(s):

Florian Meirer ◽

Sam Kalirai ◽

Darius Morris ◽

Santosh Soparawalla ◽

Yijin Liu ◽

...

Keyword(s):

Catalytic Cracking ◽

Catalyst Deactivation ◽

Product Distribution ◽

Metal Deposition ◽

Nickel Deposition ◽

Near Surface ◽

Life And Death ◽

Complex Particle ◽

Catalytically Active ◽

And Shifts

Fluid catalytic cracking (FCC) particles account for 40 to 45% of worldwide gasoline production. The hierarchical complex particle pore structure allows access of long-chain feedstock molecules into active catalyst domains where they are cracked into smaller, more valuable hydrocarbon products (for example, gasoline). In this process, metal deposition and intrusion is a major cause for irreversible catalyst deactivation and shifts in product distribution. We used x-ray nanotomography of industrial FCC particles at differing degrees of deactivation to quantify changes in single-particle macroporosity and pore connectivity, correlated to iron and nickel deposition. Our study reveals that these metals are incorporated almost exclusively in near-surface regions, severely limiting macropore accessibility as metal concentrations increase. Because macropore channels are “highways” of the pore network, blocking them prevents feedstock molecules from reaching the catalytically active domains. Consequently, metal deposition reduces conversion with time on stream because the internal pore volume, although itself unobstructed, becomes largely inaccessible.

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A Model of Catalytic Cracking: Catalyst Deactivation Induced by Feedstock and Process Variables

Catalysts ◽

10.3390/catal12010098 ◽

2022 ◽

Vol 12 (1) ◽

pp. 98

Author(s):

Galina Y. Nazarova ◽

Elena N. Ivashkina ◽

Emiliya D. Ivanchina ◽

Maria Y. Mezhova

Keyword(s):

Catalytic Cracking ◽

Catalyst Deactivation ◽

Coke Formation ◽

Experimental Studies ◽

Main Process ◽

Process Variables ◽

Coke Content ◽

Petroleum Fractions ◽

Spent Catalysts

Changes in the quality of the feedstocks generated by involving various petroleum fractions in catalytic cracking significantly affect catalyst deactivation, which stems from coke formed on the catalyst surface. By conducting experimental studies on feedstocks and catalysts, as well as using industrial data, we studied how the content of saturates, aromatics and resins (SAR) in feedstock and the main process variables, including temperature, consumptions of the feedstock, catalyst and slops, influence the formation of catalytic coke. We also determined catalyst deactivation patterns using TG-DTA, N2 adsorption and TPD, which were further used as a basis for a kinetic model of catalytic cracking. This model helps predict the changes in reactions rates caused by coke formation and, also, evaluates quantitatively how group characteristics of the feedstock, the catalyst-to-oil ratio and slop flow influence the coke content on the catalyst and the degree of catalyst deactivation. We defined that a total loss of acidity changes from 8.6 to 30.4 wt% for spent catalysts, and this depends on SAR content in feedstock and process variables. The results show that despite enriching the feedstock by saturates, the highest coke yields (4.6–5.2 wt%) may be produced due to the high content of resins (2.1–3.5 wt%).

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A Hybrid FCC/HZSM-5 Catalyst for the Catalytic Cracking of a VGO/Bio-Oil Blend in FCC Conditions

Catalysts ◽

10.3390/catal10101157 ◽

2020 ◽

Vol 10 (10) ◽

pp. 1157

Author(s):

Álvaro Ibarra ◽

Idoia Hita ◽

José M. Arandes ◽

Javier Bilbao

Keyword(s):

Catalytic Cracking ◽

Hydrogen Transfer ◽

Product Distribution ◽

Vacuum Gasoil ◽

Light Cycle ◽

Light Cycle Oil ◽

Riser Reactor ◽

Bio Oil ◽

Cycle Oil ◽

Oil Blend

The performance of a commercial FCC catalyst (designated as CY) and a physically mixed hybrid catalyst (80 wt.% CY and 20 wt.% HZSM-5-based catalyst, designated as CH) have been compared in the catalytic cracking of a vacuum gasoil (VGO)/bio-oil blend (80/20 wt.%) in a simulated riser reactor (C/O, 6gcatgfeed−1; t, 6 s). The effect of cracking temperature has been studied on product distribution (carbon products, water, and coke) and product lumps: CO+CO2, dry gas, liquified petroleum gases (LPG), gasoline, light cycle oil (LCO), heavy cycle oil (HCO), and coke. Using the CH catalyst, the conversion of the bio-oil oxygenates is ca. 3 wt.% higher, while the conversion of the hydrocarbons in the mixture is lower, yielding more carbon products (83.2–84.7 wt.% on a wet basis) and less coke (3.7–4.8 wt.% on a wet basis) than the CY catalyst. The CH catalyst provides lower gasoline yields (30.7–32.0 wt.% on a dry basis) of a less aromatic and more olefinic nature. Due to gasoline overcracking, enhanced LPG yields were also obtained. The results are explained by the high activity of the HZSM-5 zeolite for the cracking of bio-oil oxygenates, the diffusional limitations within its pore structure of bulkier VGO compounds, and its lower activity towards hydrogen transfer reactions.

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An analytical microscopic study of metals in fluidized catalytic cracking catalyst

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100145613 ◽

1986 ◽

Vol 44 ◽

pp. 854-855

Author(s):

Clifford S. Rainey

Keyword(s):

Electron Microscopy ◽

Spatial Distribution ◽

Catalytic Cracking ◽

Catalyst Deactivation ◽

Coke Formation ◽

Acid Sites ◽

Y Zeolite ◽

Fcc Catalyst ◽

Fluidized Catalytic Cracking ◽

High Regeneration

The spatial distribution of V and Ni deposited within fluidized catalytic cracking (FCC) catalyst is studied because these metals contribute to catalyst deactivation. Y zeolite in FCC microspheres are high SiO2 aluminosilicates with molecular-sized channels that contain a mixture of lanthanoids. They must withstand high regeneration temperatures and retain acid sites needed for cracking of hydrocarbons, a process essential for efficient gasoline production. Zeolite in combination with V to form vanadates, or less diffusion in the channels due to coke formation, may deactivate catalyst. Other factors such as metal "skins", microsphere sintering, and attrition may also be involved. SEM of FCC fracture surfaces, AEM of Y zeolite, and electron microscopy of this work are developed to better understand and minimize catalyst deactivation.

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Experimental studies of catalyst deactivation due to carbon and sulphur during CO 2 reforming of CH 4 over Ni washcoated monolith in the presence of H 2 S

The Canadian Journal of Chemical Engineering ◽

10.1002/cjce.24266 ◽

2021 ◽

Author(s):

Vivek Pawar ◽

Prakash V. Ponugoti ◽

Vinod M. Janardhanan ◽

Srinivas Appari

Keyword(s):

Catalyst Deactivation ◽

Experimental Studies

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A new approach on catalytic cracking catalyst deactivation

Catalysis Letters ◽

10.1007/bf00765041 ◽

1992 ◽

Vol 13 (4) ◽

pp. 383-387 ◽

Cited By ~ 2

Author(s):

Nelson P. Mart�nez ◽

Andr�s M. Quesada P.

Keyword(s):

Catalytic Cracking ◽

Catalyst Deactivation ◽

New Approach

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Bio-oil transformation into 2nd generation biofuels

Paliva ◽

10.35933/paliva.2020.03.04 ◽

2020 ◽

pp. 98-106

Author(s):

Tomáš Macek ◽

Miloš Auersvald ◽

Petr Straka

Keyword(s):

Catalytic Cracking ◽

Catalyst Deactivation ◽

Commercial Application ◽

Petroleum Feedstock ◽

2Nd Generation ◽

Marine Transport ◽

Petroleum Fractions ◽

Bio Oil ◽

The Usa ◽

Refining Processes

The article summarized the possible transformations of pyrolysis bio-oil from lignocellulose into 2nd generation biofuels. Although a lot has been published about this topic, so far, none of the published catalytic pro-cesses has found commercial application due to the rapid deactivation of the catalyst. Most researches deal with bio-oil hydrotreatment at severe conditions or its pro-cessing by catalytic cracking to prepare 2nd generation biofuels directly. However, this approach is not commercially applicable due to high consumptions of hydrogen and fast catalyst deactivation. Another way, crude bio-oil co-processing with petroleum fractions in hydrotreatment or FCC units seems to be more promising. The last approach, bio-oil mild hydrotreatment followed by final co-processing with petroleum feedstock using common refining processes (FCC and hydrotreatment) seems to be the most promising way to produce 2nd generation biofuels from pyrolysis bio-oil. Co-processing of bio-oil with petroleum fraction in FCC increases conversion to gasoline and, thus, it could be a preferable process in the USA. Otherwise, co-hydrotreatment of hydrotreated bio-oil with LCO leads not only to the reduction of hydrogen consumption but also to the conversion preferably to diesel. This process seems to be more suitable for Europe. Further research on bio-oils upgrading is still necessary before the commercialization of the bio-oil conversion into biofuels suitable for cars. However, the first commercial bio-refinery that will convert bio-oil into biofuel for marine transport is planned to be built in the Netherlands.

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