Search

Your search keyword '"Thomas, Karine"' showing total 84 results
Start Over Author "Thomas, Karine"
84 results on '"Thomas, Karine"'

18. Liquid solid IR study of the interact of N compounds experiments and theory

Author

Thomas, Karine, Khalil, Ibrahim, Celis Cornejo, Carlos, Paul, Jean-Francois, Bazin, Philippe, Perez-Ramirez, Javier, Baldovino Medrano, V G, Maugé, Francoise, Laboratoire catalyse et spectrochimie (LCS), Centre National de la Recherche Scientifique (CNRS)-École Nationale Supérieure d'Ingénieurs de Caen (ENSICAEN), Normandie Université (NU)-Normandie Université (NU)-Institut de Chimie du CNRS (INC)-Université de Caen Normandie (UNICAEN), Normandie Université (NU), Unité de Catalyse et Chimie du Solide - UMR 8181 (UCCS), Centrale Lille Institut (CLIL)-Université d'Artois (UA)-Centrale Lille-Centre National de la Recherche Scientifique (CNRS)-Institut de Chimie du CNRS (INC)-Université de Lille, Eidgenössische Technische Hochschule - Swiss Federal Institute of Technology [Zürich] (ETH Zürich), MIMOSA EMC3, Université de Caen Normandie (UNICAEN), Normandie Université (NU)-Normandie Université (NU)-École Nationale Supérieure d'Ingénieurs de Caen (ENSICAEN), Normandie Université (NU)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS), and Université d'Artois (UA)-Centrale Lille-Institut de Chimie du CNRS (INC)-Université de Lille-Centre National de la Recherche Scientifique (CNRS)

Subjects
[CHIM]Chemical Sciences, ComputingMilieux_MISCELLANEOUS
Abstract

International audience

Published
2019

19. Liquid-solid IR study of the interaction of N-compounds with HY zeolites. Experimental and theoretical approaches

Author

Thomas, Karine, Khalil, Ibrahim, Celis Cornejo, Carlos, Paul, Jean-Francois, Bazin, Philippe, Pérez-Martínez, David J., Baldovino-Medrano, Víctor G., Maugé, Françoise, Laboratoire catalyse et spectrochimie (LCS), Université de Caen Normandie (UNICAEN), Normandie Université (NU)-Normandie Université (NU)-École Nationale Supérieure d'Ingénieurs de Caen (ENSICAEN), Normandie Université (NU)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS), Unité de Catalyse et Chimie du Solide - UMR 8181 (UCCS), Université d'Artois (UA)-Centrale Lille-Institut de Chimie du CNRS (INC)-Université de Lille-Centre National de la Recherche Scientifique (CNRS), Universidad Industrial de Santander [Bucaramanga] (UIS), Centre National de la Recherche Scientifique (CNRS)-École Nationale Supérieure d'Ingénieurs de Caen (ENSICAEN), Normandie Université (NU)-Normandie Université (NU)-Institut de Chimie du CNRS (INC)-Université de Caen Normandie (UNICAEN), Normandie Université (NU), and Centrale Lille Institut (CLIL)-Université d'Artois (UA)-Centrale Lille-Centre National de la Recherche Scientifique (CNRS)-Institut de Chimie du CNRS (INC)-Université de Lille

Subjects
[CHIM.THEO]Chemical Sciences/Theoretical and/or physical chemistry, ComputingMilieux_MISCELLANEOUS
Abstract

International audience

Published
2019

20. Development of in situ liquid-solid IR-ATR methodology for the study of pyridine and indole adsorption on zeolites

Author

Thomas, Karine, Khalil, Ibrahim, Celis Cornejo, Carlos, Paul, Jean-Francois, Bazin, Philippe, Travert, Arnaud, Pérez-Martínez, David J., Baldovino-Medrano, Víctor G., Maugé, Françoise, Laboratoire catalyse et spectrochimie (LCS), Université de Caen Normandie (UNICAEN), Normandie Université (NU)-Normandie Université (NU)-École Nationale Supérieure d'Ingénieurs de Caen (ENSICAEN), Normandie Université (NU)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS), Universidad Industrial de Santander [Bucaramanga] (UIS), Unité de Catalyse et Chimie du Solide - UMR 8181 (UCCS), Université d'Artois (UA)-Centrale Lille-Institut de Chimie du CNRS (INC)-Université de Lille-Centre National de la Recherche Scientifique (CNRS), Centre National de la Recherche Scientifique (CNRS)-École Nationale Supérieure d'Ingénieurs de Caen (ENSICAEN), Normandie Université (NU)-Normandie Université (NU)-Institut de Chimie du CNRS (INC)-Université de Caen Normandie (UNICAEN), Normandie Université (NU), and Centrale Lille Institut (CLIL)-Université d'Artois (UA)-Centrale Lille-Centre National de la Recherche Scientifique (CNRS)-Institut de Chimie du CNRS (INC)-Université de Lille

Subjects
[CHIM.THEO]Chemical Sciences/Theoretical and/or physical chemistry, ComputingMilieux_MISCELLANEOUS
Abstract

International audience

Published
2019

21. Déficits phonologiques et morphologiques chez des enfants dyslexiques francophones

Author

Sabater, Carine, Baudet, Valérie, Habib, Michel, Prost, Véronique, Thomas, Karine, and Rey, Véronique

Subjects
Language & Linguistics, lecture, langue arabe, LAN009000, CF, Education & Educational Research, apprentissage
Abstract

La dyslexie phonologique développementale se caractérise par un trouble d'apprentissage qui s'observe chez les enfants au moment de l'acquisition du langage écrit. Les critères permettant, selon l'Organisation Mondiale de la Santé, de faire le diagnostic de la dyslexie sont : un retard en lecture de deux ans en dessous de l'âge chronologique, un quotient intellectuel normal (supérieur à 70), et l'absence d'un déficit d'acuité visuelle ou auditive ou d'une affection neurologique. De nombreux c...

Published
2019

22. L'apprentissage de la lecture

Author

Alegria, J., Alvarez-Cienfuegos, Carmen, Ammar, Mohamed, Armand, Françoise, Baccouche, Taieb, Bastien, Claude, Bastien-Toniazzo, Mireille, Baudet, Valérie, Belajouza, Michèle, Belkadhi, Alia Maaouia, Boukadida, Nahed, Bruckert, Jean Pierre, Carrillo, Marisol, Carrillo, S., Citoler, Silvia Defior, Demont, Elisabeth, Derguini, Meriem, de Koninck, Zita, Doignon, Nadège, Ecalle, Jean, Eme, Elsa, Fadhel, Slah Eddine Ben, Gombert, Jean Emile, Habib, Michel, Haro, Carol, Jaffré, Jean-Pierre, Jourdain, Christine, Lete, Bernard, Magnan, Annie, Marin, J., Mekideche, Tchirine, Mousty, Ph., Najem, Aida, Prost, Véronique, Rey, Véronique, Romdhane, Mohamed Nouri, Rouet, Jean-François, Sabater, Carine, Sanguin-Bruckert, Christine, Thomas, Karine, Tønnessen, Finn Egil, Torres, Lucia Herrera, Zagar, Daniel, Ziarko, Hélène, Nouri Romdhane, Mohamed, Gombert, Jean Emile, and Belajouza, Michèle

Subjects
Language & Linguistics, lecture, langue arabe, LAN009000, CF, Education & Educational Research, apprentissage
Abstract

Cet ouvrage est le premier rapportant un tel nombre de travaux sur l'apprentissage de la lecture en langue arabe. En cela, il ouvre la voie au développement de comparaisons, au sein des langues alphabétiques, entre écritures latines et sémitiques. Au-delà des différences évidentes des graphies, les spécificités linguistiques (notamment phonologiques, morphologiques et syntaxiques) des langues sémitiques et de leurs transcriptions écrites sont susceptibles de renouveler de façon très importante les modèles d'acquisition. Ces modèles n'étaient jusqu'alors étayés que par des données obtenues dans des langues à écriture latine (essentiellement l'anglais). Les premiers résultats disponibles sur l'hébreu et rapportés ici sur l'arabe, confortent les principes généraux de ces modèles, mais les modulent également, notamment en mettant en évidence un rôle plus important de la morphologie. Les textes réunis dans cet ouvrage sont issus des communications présentées lors d'un colloque qui s'est déroulé fin novembre 2000 à Carthage (Tunisie). Cette rencontre scientifique a permis à des chercheurs de huit nationalités différentes de confronter les résultats de leurs recherches sur l'apprentissage de la lecture. Le colloque se fixait essentiellement deux objectifs : faire le point sur les connaissances concernant l'apprentissage de la lecture et ses difficultés, et explorer, à partir d'études inter-langues, le rôle des contraintes liées aux caractéristiques de la langue d'apprentissage.

Published
2019

25. Catalytic upgrading of bio‐oil: Hydrodeoxygenation study of acetone as molecule model of ketones.

Author

Wang, Jundong, Jabbour, Michael, Abdelouahed, Lokmane, Mezghich, Soumaya, Estel, Lionel, Thomas, Karine, and Taouk, Bechara

Subjects
ACETONE, MOLECULAR models, HEXONE, KETONES, ACETALDEHYDE, AROMATIC compounds, ALDOL condensation
Abstract

The complexity of composition of bio‐oil from biomass makes it difficult to produce upgraded bio‐oil via hydrodeoxygenation. In this paper, acetone is thus considered as a model compound of the ketones family abundant in pyrolysis bio‐oil. Results showed that high conversion rates of acetone between 86.6% and 91.9% were observed with the use of HZSM‐5, 5% Ni2P/HZSM‐5, and 10% Ni2P/HZSM‐5 catalysts. In most cases, CO2, C2H6, C3H6, and C3H8 were the dominant non‐condensable gas products. For liquid phase, the selectivity was evaluated for different catalysts relative to ethanol, acetaldehyde, and aromatic hydrocarbons. A lower temperature favoured the formation of acetaldehyde and methyl isobutyl ketone with the 5% Ni2P/HZSM‐5 catalyst, while higher temperatures increased the proportion of aromatic hydrocarbons. The principal influencing parameters of acetone HDO were temperature and contact time followed by reaction pressure and H2 partial pressure. Optimal conditions give a selectivity of 49% of aromatics (benzene, toluene, and xylene) with the use of the 5% Ni2P/HZSM‐5 catalyst. The pathway of the main reactions of acetone HDO was also proposed. MIK and aromatic hydrocarbons were formed by a multiple step aldol condensation reaction of acetone molecules followed by further hydrogenation. [ABSTRACT FROM AUTHOR]

Published
2021
Full Text
View/download PDF

26. In situ and operando IR-ATR spectroscopy for investigation of solid-liquid interfaces by adsorption or catalytic processes for fuel purification

Author

Khalil, Ibrahim, Celis Cornejo, Carlos, Thomas, Karine, Baldovino Medrano, V G, Paul, J.F., Maugé, Françoise, Laboratoire catalyse et spectrochimie (LCS), Centre National de la Recherche Scientifique (CNRS)-École Nationale Supérieure d'Ingénieurs de Caen (ENSICAEN), Normandie Université (NU)-Normandie Université (NU)-Institut de Chimie du CNRS (INC)-Université de Caen Normandie (UNICAEN), Normandie Université (NU), Unité de Catalyse et Chimie du Solide - UMR 8181 (UCCS), Centrale Lille Institut (CLIL)-Université d'Artois (UA)-Centrale Lille-Centre National de la Recherche Scientifique (CNRS)-Institut de Chimie du CNRS (INC)-Université de Lille, Université de Caen Normandie (UNICAEN), Normandie Université (NU)-Normandie Université (NU)-École Nationale Supérieure d'Ingénieurs de Caen (ENSICAEN), Normandie Université (NU)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS), and Université d'Artois (UA)-Centrale Lille-Institut de Chimie du CNRS (INC)-Université de Lille-Centre National de la Recherche Scientifique (CNRS)

Subjects
[CHIM]Chemical Sciences, ComputingMilieux_MISCELLANEOUS
Abstract

International audience

Published
2018

29. Purification of 2nd generation bio-fuels by selective adsorption of phenol.Quantitative tests and operando IR-ATR study over various adsorbent

Author

Khalil, Ibrahim, Thomas, Karine, Dominguez garcia, Elizabeth, Mauge, Françoise, PERRIER, Nathalie, Laboratoire catalyse et spectrochimie (LCS), Centre National de la Recherche Scientifique (CNRS)-École Nationale Supérieure d'Ingénieurs de Caen (ENSICAEN), Normandie Université (NU)-Normandie Université (NU)-Institut de Chimie du CNRS (INC)-Université de Caen Normandie (UNICAEN), and Normandie Université (NU)

Subjects
[CHIM] Chemical Sciences, [CHIM]Chemical Sciences, ComputingMilieux_MISCELLANEOUS
Abstract

International audience

Published
2017

30. Etude IR-ATR de l’adsorption du phénol en phase liquide sur alumine

Author

Khalil, Ibrahim, Thomas, Karine, Maugé, Françoise, PERRIER, Nathalie, Laboratoire catalyse et spectrochimie (LCS), Centre National de la Recherche Scientifique (CNRS)-École Nationale Supérieure d'Ingénieurs de Caen (ENSICAEN), Normandie Université (NU)-Normandie Université (NU)-Institut de Chimie du CNRS (INC)-Université de Caen Normandie (UNICAEN), and Normandie Université (NU)

Subjects
[CHIM] Chemical Sciences, [CHIM]Chemical Sciences, ComputingMilieux_MISCELLANEOUS
Abstract

National audience

Published
2017

31. In Situ IR‐ATR Study of the Interaction of Nitrogen Heteroaromatic Compounds with HY Zeolites: Experimental and Theoretical Approaches.

Author

Khalil, Ibrahim, Celis‐Cornejo, Carlos M., Thomas, Karine, Bazin, Philippe, Travert, Arnaud, Pérez‐Martínez, David J., Baldovino‐Medrano, Víctor G., Paul, Jean François, and Maugé, Françoise

Subjects
NITROGEN compounds, INDOLE, DENSITY functional theory, VAPOR pressure, ZEOLITES, ORGANONITROGEN compounds, PETROLEUM refineries
Abstract

In the present work, the liquid‐solid interaction of liquid N‐heteroaromatic compounds, commonly present in the petroleum feedstocks of the refineries, with Y zeolites used as hydrocracking catalysts was followed using IR‐ATR spectroscopy. The inhibition of the zeolitic acid sites by strongly basic pyridine and weakly basic indole was highlighted using a continuous flow IR‐ATR cell. Results were assessed by Density Functional Theory calculations to compute the vibrational frequencies of pyridine and indole according to the nature of the interaction sites: silanol groups or acidic OH groups. The study points out that IR‐ATR spectroscopy opens the way for investigating the interaction modes of low vapor pressure molecules (e. g. indole) that present an inherent difficulty to be operated in the gas phase. Moreover, the IR‐ATR makes possible the analysis of the little‐explored low wavenumber zone (<800 cm−1), that presents informative vibrational modes on the adsorption mode of N‐molecules. Hence, this work points out that for pyridine, the bands at 686 and 727 cm−1 are characteristic of pyridinium species formed over zeolitic OH groups, meanwhile, the signals at 703 and 750 cm−1, are associated to pyridine in interaction with silanol groups. The IR‐ATR study reveals that indole, a weakly basic compound, can be protonated on acidic Y zeolites as unambiguously evidenced by the formation of the bands at 1617, 1608, 1543 and 705 cm−1. Findings here exposed are crucial for studying inhibitory effects exerted by weak nitrogenated compounds on acidic materials during hydrocracking processes. [ABSTRACT FROM AUTHOR]

Published
2020
Full Text
View/download PDF

37. Etude exploratoire des capacités phonologiques chez les enfants présentant un déficit de langage

Author

Rey, Véronique, Tardif, Carole, Delahaie, Marc, Vol, Sylviane, Thomas, Karine, Massion, Jean, Laboratoire Parole et Langage (LPL), and Aix Marseille Université (AMU)-Centre National de la Recherche Scientifique (CNRS)

Subjects
autisme, phonological awareness, dysphasie, conscience phonologique, autism, dysphasia, [SHS.LANGUE]Humanities and Social Sciences/Linguistics
Abstract

Research on the language of autiste and dysphasia subjects remained essentially descriptive, resting (basing) most of the time on descriptions of deficit of speech and not of language. The comment of this study is to know more exactly presence or not of a disturbance of the phonological system at these children. Paradigm of the category-specific identification on an opposition of place of articulation was tested with these children, compared with children witnesses. Results seem to show that the difficulty of identification of the children is less in intra-category-specific identification than in inter-category-specific.; Les recherches sur le langage des sujets autistes et dysphasiques sont restées essentiellement descriptives, reposant la plupart du temps sur des descriptions de deficit de langage et non de bilan de langue. Le propos de cette étude est de connaître plus précisément la présence ou non d'une perturbation du système phonologique chez ces enfants-là. Le paradigme de l'identification catégorielle sur une opposition de lieu d'articulation fut testé auprès de ces enfants, comparés à des enfants témoins. Les résultats semblent montrer que la difficulté d'identification des enfants est moins en identification intra-catégorielle qu'en inter-catégorielle.

Published
2001

40. Platinum Supported Catalysts: Predictive CO and H2Chemisorption by a Statistical Cuboctahedron Cluster Model

Author

Le Valant, Anthony, Comminges, Clément, Can, Fabien, Thomas, Karine, Houalla, Marwan, and Epron, Florence

Abstract

Chemisorption of probe molecules such as hydrogen and carbon monoxide on the surface of Pt particles is the most common chemical technique used to estimate the crucial parameters of metal catalysts, namely the dispersion (D), the particle size (d), and the metallic specific surface area (SPt). However, it remains a controversy concerning the stoichiometry of adsorbate per surface metal atom, leading to an inaccurate estimation of D, d, and SPt. A model describing the statistics of the surface atoms and sites on perfect cuboctahedron clusters was developed to assess values of D, d, and SPt, assuming the most favorable adsorption sites based on density functional theory (DFT) calculation of the literature. This model successfully predicted the experimental values of D, d, and SPtdetermined from H or CO chemisorption data, and it allowed providing a set of simple equations for the accurate determination of these parameters from chemisorption experiments on Pt.

Published
2016
Full Text
View/download PDF

43. Study of Ir/WO3/Al2O3 ring opening catalysts

Author

Park, Jie-Won, primary, Thomas, Karine, additional, van Gestel, Jacob, additional, Gilson, Jean-Pierre, additional, Collet, Christine, additional, Dath, Jean-Pierre, additional, and Houalla, Marwan, additional

Published
2010
Full Text
View/download PDF

47. Hydroisomerization and hydrocracking activity enhancement of a hierarchical ZSM-5 zeolite catalyst viaatomic layer deposition of aluminium

Author

Sree, Sreeprasanth Pulinthanathu, Dendooven, Jolien, MagusinPresent address: The Grey Group, Pieter C. M. M., Chemistry, Department of, Cambridge, University of, Lensfield, Thomas, Karine, Gilson, Jean-Pierre, Taulelle, Francis, Detavernier, Christophe, and Martens, Johan A.

Abstract

Desilication of a ZSM-5 zeolite in basic medium creates intracrystalline mesoporosity advantageous for catalysis, but a decrease in acidity often limits the gain by improved accessibility of sites. Atomic layer deposition of aluminium (Al-ALD) using cycles of reaction and hydrolysis of trimethylaluminum was applied to desilicated ZSM-5 samples to enhance acidity. Framework as well as extra-framework aluminium species were introduced. Removal of extra-framework aluminium viamild acid leaching was beneficial to the acidity. The Al-ALD modified ZSM-5 specimen showed improved dispersion of platinum introduced viaimpregnation of a Pt(NH3)4Cl2precursor followed by oxidation and reduction. Hydroisomerization and hydrocracking performance was very sensitive to the ZSM-5 zeolite modification with Al-ALD. The hierarchical sample from which the excess of deposited aluminium was removed showed the best penetration of platinum to the interior and was most active. It outperformed the original ZSM-5 zeolite in activity and hydroisomerization selectivity. Alumina deposited by Al-ALD on the external surface of the ZSM-5 zeolite particles is a preferential location for platinum deposition. Such a catalyst with externally positioned Pt was most selective for hydroisomerization.

Published
2016
Full Text
View/download PDF

48. Comparative Influence of Surface Tungstate Species and Bulk Amorphous WO3Particles on the Acidity and Catalytic Activity of Tungsten Oxide Supported on Silica

Author

Chauvin, Jeanne, Thomas, Karine, Clet, Guillaume, and Houalla, Marwan

Abstract

Catalysts based on tungsten oxide supported on silica and containing up to 2.5 W atoms nm–2were studied for the purpose of establishing quantitative relationships between the nature and abundance of surface species, acidity, and catalytic activity. Synthesis conditions that maximize the formation of amorphous WO3were adopted to assess its influence on the overall acidity and activity. The results were compared to those of conventionally prepared catalysts. The catalysts’ structure was characterized by FTIR, Raman, and UV spectroscopies. The acidity of the solids was monitored by adsorption of 2,6-dimethylpyridine followed by FTIR, and their catalytic activity was tested for the reaction of propan-2-ol dehydration. A methodology for quantitation of W species (WOxsurface species, amorphous or crystalline WO3particles) detected following calcination at 673 or 773 K was developed. For both calcination temperatures, surface W species were first formed with initial W addition. Their abundance increased with increasing W content up to ca. 0.7 atom W nm–2and levels off for higher W surface densities. The leveling off was concomitant with the detection and rapid development of amorphous or crystalline WO3phase (catalysts calcined respectively at 673 or 773 K). The comparison of W speciation in both series indicated that amorphous WO3phase is quantitatively transformed to crystalline WO3on increasing the calcination temperature from 673 to 773 K. The observed development of Brønsted acidity of the solids was associated with W deposition. The abundance of these acid sites correlated directly with the catalytic activity. The study of structure–activity relationship showed that all W species were active. Modeling of the results permitted an estimation of the intrinsic activity of each W species. The values thus obtained suggest that amorphous WO3particles exhibit the highest activity per surface W atom.

Published
2015
Full Text
View/download PDF

49. Ring opening of decalin and methylcyclohexane over bifunctional Ir/WO3/Al2O3 catalysts

Author

Moraes, Rodrigo, Thomas, Karine, Thomas, Sébastien, Van Donk, Sander, Grasso, Giacomo, Gilson, Jean-Pierre, and Houalla, Marwan

Subjects
*RING-opening reactions, *DECAHYDRONAPHTHALENE, *CYCLOHEXANE, *CATALYSTS, *ALUMINUM oxide, *TUNGSTEN oxides, *IRIDIUM, *INFRARED spectroscopy, *LOW temperatures
Abstract

Abstract: Ring-opening reactions of decalin and methylcyclohexane (MCH) over bifunctional catalysts (1.2Ir/WO3/Al2O3) were investigated. A series of catalysts containing up to 5.3at. W/nm2 and 1.2wt.% Ir was prepared. The acidity of the solids was monitored by low-temperature CO adsorption followed by infrared spectroscopy. Characterization of the Ir metal phase was performed by H2 chemisorption and X-ray diffraction. The activity and product selectivity patterns obtained for the decalin ring-opening reaction were compared with those observed for MCH. For both naphthenes, ring contraction precedes ring opening, suggesting a similar ring-opening mechanism. Kinetic modeling based on the proposed reaction network allowed the determination of the activation energies and initial rates. Based on the yields and products distribution obtained for the decalin reaction, the potential for improvement of the cetane number is discussed. [Copyright &y& Elsevier]

Published
2013
Full Text
View/download PDF

50. Ring opening of decalin and methylcyclohexane over alumina-based monofunctional WO3/Al2O3 and Ir/Al2O3 catalysts

Author

Moraes, Rodrigo, Thomas, Karine, Thomas, Sébastien, Van Donk, Sander, Grasso, Giacomo, Gilson, Jean-Pierre, and Houalla, Marwan

Subjects
*DECAHYDRONAPHTHALENE, *CYCLOHEXANE, *ALUMINUM oxide, *TUNGSTEN oxides, *METAL catalysts, *RING-opening reactions, *METHYLCYCLOHEXENONES, *RAMAN spectroscopy
Abstract

Abstract: Ring-opening reactions of decalin and MCH were studied over monofunctional acid (WO3/Al2O3) and metal (Ir/Al2O3) catalysts containing, respectively, up to 5.3 at. W/nm2 and 1.8wt% Ir. The catalysts were characterized by X-ray diffraction, Raman spectroscopy, low-temperature CO adsorption followed by infrared spectroscopy, and H2 chemisorption. A reaction network was proposed for both molecules and used to determine the kinetic parameters. Kinetic modeling allowed relating characterization results and catalytic performance. For WO3/Al2O3 catalysts, ring contraction precedes ring opening of both molecules. The evolution of ring contraction activity was consistent with the development of relatively strong Brønsted acid sites. Ring opening occurs according to a classic acid mechanism. For Ir/Al2O3 catalysts, only direct ring opening was observed. Ring opening proceeds mostly via dicarbene mechanism. Analysis of products indicated that monofunctional metal catalysts are better suited than acid solids for upgrading LCO. [Copyright &y& Elsevier]

Published
2012
Full Text
View/download PDF

Catalog

Books, media, physical & digital resources
See catalog results