Adsorption, Diffusion, and Reaction Phenomena on FCC Catalysts in the CREC Riser Simulator

and, J. A. Atias; Lasa, Hugo de

doi:10.1021/ie034197q

Cited by 17 publications

(20 citation statements)

References 28 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…One can thus notice in Table that TIBP molecules have a critical molecular diameter of 9.4 A. This is similar in size to the 7.4 A Y zeolite pores. , Thus, the TIPB molecules may be transported under hindered diffusion, , with coke formation potentially influencing TIPB transport further.…”

Section: Experimental Procedures and Apparatusmentioning

confidence: 79%

“…This was done to characterize catalyst activity and to examine the effects of the C/O ratio on hydrocarbon conversion and product selectivity. The TIPB was selected given that it contains a good balance of aromatic and iso-paraffin functionalities. , Al-khattaf et al, Qin et al, and Varshney et al pointed out that TIPB is a valuable model species to study the relative importance of diffusion and chemical reactions in FCC.…”

Section: Experimental Procedures and Apparatusmentioning

confidence: 99%

“…In the last 15 years, significant research efforts have been made to clarify the kinetics of the catalytic cracking of hydrocarbons using both VGO and model compounds and a new experimental device designated as the CREC Riser Simulator. − The CREC Riser Simulator is a unique experimental bench-scale reactor, which mimics the reaction conditions of an FCC industrial circulating fluidized bed unit. These reaction conditions are temperature, partial pressures of hydrocarbons, and contact time. − In the CREC Riser Simulator, C/O ratios are established on a sound basis: the ratio of the weight of the catalyst over the weight of hydrocarbon feedstock fed.…”

Section: Introductionmentioning

confidence: 99%

See 2 more Smart Citations

Catalytic Cracking of Hydrocarbons in a CREC Riser Simulator Using a Y-Zeolite-Based Catalyst: Assessing the Catalyst/Oil Ratio Effect

Alkhlel

Lasa

2018

Ind. Eng. Chem. Res.

Self Cite

View full text Add to dashboard Cite

The present study investigates the effects of the changes of the catalyst to feedstock ratio (C/O) on FCC cracking using a Y-zeolite-based catalyst. Experiments are developed in a CREC Riser Simulator. This bench-scale mini-fluidized batch unit mimics the operating conditions of large-scale FCC units as follows: It uses temperatures ranging from 510 to 550 °C and reaction times from 3 7 s. For every experiment, 0.2 g of 1,3,5-TIPB is contacted with a 0.12–1g catalyst amount. This is done to achieve a C/O ratio in the range of 0.6–5. Experiments show the effects of increasing the C/O ratio on 1,3,5-TIPB conversion, coke formation, and product selectivity. On this basis, a mechanism involving single catalyst sites for cracking and two sites for coke formation is considered. Coke formation is postulated as an additive process involving coke precursor species, which are either adsorbed on sites in the same particle or adsorbed in close sites in different particles. The proposed mechanism helps explain the results obtained, introducing a rationale for the selection of optimum C/O ratios to yield the highest possible 1,3,5-TIPB conversions with controlled amounts of coke formation. It is anticipated that the findings of this study will have a significant influence on the selection of an optimum C/O ratio for the design and operation of the most advanced FCC risers and downers.

show abstract

Section: Experimental Procedures and Apparatusmentioning

confidence: 79%

Section: Experimental Procedures and Apparatusmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

Catalytic Cracking of Hydrocarbons in a CREC Riser Simulator Using a Y-Zeolite-Based Catalyst: Assessing the Catalyst/Oil Ratio Effect

Alkhlel

Lasa

2018

Ind. Eng. Chem. Res.

Self Cite

View full text Add to dashboard Cite

show abstract

“…It should be mentioned here that the second-order kinetic constants estimated in this work employed an oversimplified model. It does not take into account the intracrystallite diffusion, which is known to affect the cracking reaction rate [39,40], especially when feeds having different molecular weights are cracked as the EBVRHC heavy oils explored in this study. Moreover, no experiments have been carried out at different reaction temperatures to define the activation energies as the kinetic studies reported in [37,38,41].…”

Section: Resultsmentioning

confidence: 99%

Catalytic Cracking of Diverse Vacuum Residue Hydrocracking Gas Oils

et al. 2021

View full text Add to dashboard Cite

Ten gas oils and one deasphalted hydrocracked vacuum residue obtained from ebullated‐bed vacuum residue hydrocracking have been cracked in a laboratory advanced catalyst evaluation unit on a commercial fluid catalytic cracking (FCC) catalyst. It was found that the eleven secondary heavy oils obey second‐order reaction kinetics. The relations between gas oil properties and FCC conversion, product yields, and quality were evaluated by means of intercriteria analysis. It could be stated that the FCC conversion strongly correlates with the gas oil Kw characterization factor. The product yields were established to depend on the secondary gas oil carbon atoms number, aromatic ring index, paraffinic and aromatic carbon content, and the total aromatics content.

show abstract

“…The 1,3,5-TIPB was selected as a model compound, given its special combination of aromatic and iso-paraffin functionalities [35]. Additionally, the 1,3,5-TIPB used is considered a valuable model species given its 9.4 A • critical molecular diameter, which allows combined diffusional and catalytic effects in Y zeolites [36][37][38][39]. All products from 1,3,5-TIPB conversion were identified and quantified using GC-MS analyses.…”

Section: Feedstock and Catalystsmentioning

confidence: 99%

Catalyst/Feedstock Ratio Effect on FCC Using Different Catalysts Samples

Alkhlel

Lasa

2019

Catalysts

View full text Add to dashboard Cite

The present study is a follow-up to a recent authors contribution which describes the effect of the C/O (catalyst/oil) ratio on catalytic cracking activity and catalyst deactivation. This study, while valuable, was limited to one fluidized catalytic cracking (FCC) catalyst. The aim of the present study is to consider the C/O effect using three FCC catalysts with different activities and acidities. Catalysts were characterized in terms of crystallinity, total acidity, specific surface Area (SSA), temperature programmed ammonia desorption (NH3-TPD), and pyridine chemisorption. 1,3,5-TIPB (1,3,5-tri-isopropyl benzene) catalytic cracking runs were carried out in a bench-scale mini-fluidized batch unit CREC (chemical reactor engineering centre) riser simulator. All data were taken at 550 °C with a contact time of 7 s. Every experiment involved 0.2 g of 1,3,5-TIPB with the amount of catalyst changing in the 0.12–1 g range. The resulting 0.6–5 g oil/g cat ratios showed a consistent 1,3,5-TIPB conversion increasing first, then stabilizing, and finally decreasing modestly. On the other hand, coke formation and undesirable benzene selectivity always rose. Thus, the reported results show that catalyst density affects both catalyst coking and deactivation, displaying an optimum C/O ratio, achieving maximum hydrocarbon conversions in FCC units.

show abstract

Adsorption, Diffusion, and Reaction Phenomena on FCC Catalysts in the CREC Riser Simulator

Cited by 17 publications

References 28 publications

Catalytic Cracking of Hydrocarbons in a CREC Riser Simulator Using a Y-Zeolite-Based Catalyst: Assessing the Catalyst/Oil Ratio Effect

Catalytic Cracking of Hydrocarbons in a CREC Riser Simulator Using a Y-Zeolite-Based Catalyst: Assessing the Catalyst/Oil Ratio Effect

Catalytic Cracking of Diverse Vacuum Residue Hydrocracking Gas Oils

Catalyst/Feedstock Ratio Effect on FCC Using Different Catalysts Samples

Contact Info

Product

Resources

About