Transient microkinetic modelling of n-heptane catalytic cracking over H-USY zeolite

2004 ◽  
Vol 59 (6) ◽  
pp. 1221-1232 ◽  
Author(s):  
H. Carabineiro ◽  
C.I.C. Pinheiro ◽  
F. Lemos ◽  
F. Ramôa Ribeiro
Author(s):  
Jesus A Atias ◽  
Gabriela M Tonetto ◽  
Hugo Ignacio de Lasa

The complexity of a heavy gas oil feedstock and the multitude of reaction pathways have limited previous attempts to model fluid catalytic cracking (FCC). The demand for more detailed kinetic information motivates the use of pure components to first elucidate the dominant pathways and mechanisms and then determine the associated rate parameters, including adsorption constants and heats of adsorption. The aim of the present work is to evaluate adsorption constants and heats of adsorption, under FCC relevant reaction conditions. The experiments are carried out in a novel CREC Riser Simulator (batch reactor unit) using USY zeolite catalysts with different crystallite sizes (0.4 and 0.9 microns). This study confirms a special feature of the CREC Riser Simulator, as a valuable tool for the study of adsorption phenomena. Adsorption constants and heats of adsorption are evaluated for benzene, toluene, xylene and trimethylbenzene, at initial reaction conditions. Catalytic conversion experiments for 1,2,4-trimethylbenzene help to demonstrate the consistency of the determined adsorption parameters at various temperatures and reaction times. In addition, adsorption constants and heats of adsorption are found to be constant throughout the reaction time and the formation of coke does not hinder the adsorption of 1,2,4-TMB, although it significantly affects the reactivity of this model compound.


2013 ◽  
Vol 3 (4) ◽  
pp. 972 ◽  
Author(s):  
Cristina Martínez ◽  
Danny Verboekend ◽  
Javier Pérez-Ramírez ◽  
Avelino Corma

2015 ◽  
Vol 58 (4-6) ◽  
pp. 334-342 ◽  
Author(s):  
Yuying Shu ◽  
Arnaud Travert ◽  
Rosann Schiller ◽  
Michael Ziebarth ◽  
Richard Wormsbecher ◽  
...  

Materials ◽  
2021 ◽  
Vol 14 (4) ◽  
pp. 1029
Author(s):  
Marta Muñoz ◽  
Irene Morales ◽  
Cátia S. Costa ◽  
Marta Multigner ◽  
Patricia de la Presa ◽  
...  

Zeolites are widely used in high-temperature oil refining processes such as fluid catalytic cracking (FCC), hydrocracking, and aromatization. Significant energy cost are associated with these processes due to the high temperatures required. The induction heating promoted by magnetic nanoparticles (MNPs) under radio frequency fields could contribute to solving this problem by providing a supplementary amount of heat in a nano-localized way, just at the active centre site where the catalytic process takes place. In this study, the potential of such a complementary route to reducing energetic requirements is evaluated. The catalytic cracking reaction under a hydrogen atmosphere (hydrocracking) applied to the conversion of plastics was taken as an application example. Thus, a commercial zeolite catalyst (H-USY) was impregnated with three different magnetic nanoparticles: nickel (Ni), cobalt (Co), maghemite (γ-Fe2O3), and their combinations and subjected to electromagnetic fields. Temperature increases of approximately 80 °C were measured for H-USY zeolite impregnated with γ-Fe2O3 and Ni-γ-Fe2O3 due to the heat released under the radio frequency fields. The potential of the resulting MNPs derived catalyst for HDPE (high-density polyethylene) conversion was also evaluated by thermogravimetric analysis (TGA) under hydrogen atmosphere. This study is a proof of concept to show that induction heating could be used in combination with traditional resistive heating as an additional energy supplier, thereby providing an interesting alternative in line with a greener technology.


2002 ◽  
Vol 41 (16) ◽  
pp. 4016-4027 ◽  
Author(s):  
Nitin Agarwal ◽  
Marco A. Sanchez-Castillo ◽  
Randy D. Cortright ◽  
Rostam J. Madon ◽  
James A. Dumesic

2019 ◽  
Vol 244 ◽  
pp. 704-708 ◽  
Author(s):  
Chantal Kassargy ◽  
Sary Awad ◽  
Gaëtan Burnens ◽  
Gaurav Upreti ◽  
Khalil Kahine ◽  
...  

Author(s):  
J.K. Lampert ◽  
G.S. Koermer ◽  
J.M. Macaoy ◽  
J.M. Chabala ◽  
R. Levi-Setti

We have used high spatial resolution imaging secondary ion mass spectrometry (SIMS) to differentiate mineralogical phases and to investigate chemical segregations in fluidized catalytic cracking (FCC) catalyst particles. The oil industry relies on heterogeneous catalysis using these catalysts to convert heavy hydrocarbon fractions into high quality gasoline and fuel oil components. Catalyst performance is strongly influenced by catalyst microstructure and composition, with different chemical reactions occurring at specific types of sites within the particle. The zeolitic portions of the particle, where the majority of the oil conversion occurs, can be clearly distinguished from the surrounding silica-alumina matrix in analytical SIMS images.The University of Chicago scanning ion microprobe (SIM) employed in this study has been described previously. For these analyses, the instrument was operated with a 40 keV, 10 pA Ga+ primary ion probe focused to a 30 nm FWHM spot. Elemental SIMS maps were obtained from 10×10 μm2 areas in times not exceeding 524s.


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