Support acidity effects of NiMo sulfide catalysts in hydrodenitrogenation of quinoline, indole and Coker Gas Oil

(1)

HAL Id: tel-01673792

https://tel.archives-ouvertes.fr/tel-01673792

Submitted on 1 Jan 2018

HAL is a multi-disciplinary open access archive for the deposit and dissemination of sci-entific research documents, whether they are pub-lished or not. The documents may come from teaching and research institutions in France or abroad, or from public or private research centers.

L’archive ouverte pluridisciplinaire HAL, est destinée au dépôt et à la diffusion de documents scientifiques de niveau recherche, publiés ou non, émanant des établissements d’enseignement et de recherche français ou étrangers, des laboratoires publics ou privés.

hydrodenitrogenation of quinoline, indole and Coker Gas

Oil

Minh Tuan Nguyen

To cite this version:

Minh Tuan Nguyen. Support acidity effects of NiMo sulfide catalysts in hydrodenitrogenation of quinoline, indole and Coker Gas Oil. Chemical engineering. Université de Lyon, 2016. English. �NNT : 2016LYSE1209�. �tel-01673792�

(2)

N° d’ordre NNT : 2016LYSE1209

THESE de DOCTORAT DE L’UNIVERSITE DE LYON

Opérée au sein de

l’Université Claude Bernard Lyon 1

Ecole Doctorale 206 Chimie, Procédés, Environnement

(Ecole Doctorale de Chimie de Lyon)

Spécialité de doctorat : Chimie

Discipline : Catalyse – Génie Chimique

Soutenue publiquement le 28/10/2016, par :

Minh Tuan NGUYEN

SUPPORT ACIDITY EFFECTS OF SULFIDE CATALYSTS

IN HYDRODENITROGENATION: FROM MODEL

MOLECULES TO GAS OIL CONVERSIONS

Devant le jury composé de :

Mme. GIROIR-FENDLER Anne Prof., Université de Lyon 1 Présidente du jury

M. THYBAUT Joris Prof., Ghent University, Belgium Rapporteur

Mme. BRUNET Sylvette Ph.D, IC2MP/CNRS-Université de Poitiers Rapporteure

M. AUBRIET Frédéric Prof., Université de Lorraine Examinateur

M. GEANTET Christophe Ph.D, IRCELYON/CNRS Directeur de thèse

Mme. TAYAKOUT Mélaz Prof., Université de Lyon 1 Co-directrice de thèse

M. PIRNGRUBER Gerhard Ph.D, IFP Energies Nouvelles Encadrant IFPEN

(3)

Président de l’Université

Président du Conseil Académique

Vice-président du Conseil d’Administration

Vice-président du Conseil Formation et Vie Universitaire Vice-président de la Commission Recherche

Directeur Général des Services

M. le Professeur Frédéric FLEURY M. le Professeur Hamda BEN HADID

M. le Professeur Didier REVEL

M. le Professeur Philippe CHEVALIER M. Fabrice VALLÉE

M. Alain HELLEU

COMPOSANTES SANTE

Faculté de Médecine Lyon Est – Claude Bernard

Faculté de Médecine et de Maïeutique Lyon Sud – Charles Mérieux

Faculté d’Odontologie

Institut des Sciences Pharmaceutiques et Biologiques Institut des Sciences et Techniques de la Réadaptation

Département de formation et Centre de Recherche en Biologie Humaine

Directeur : M. le Professeur J. ETIENNE Directeur : Mme la Professeure C. BURILLON Directeur : M. le Professeur D. BOURGEOIS Directeur : Mme la Professeure C. VINCIGUERRA Directeur : M. X. PERROT

Directeur : Mme la Professeure A-M. SCHOTT

COMPOSANTES ET DEPARTEMENTS DE SCIENCES ET TECHNOLOGIE

Faculté des Sciences et Technologies Département Biologie

Département Chimie Biochimie Département GEP

Département Informatique Département Mathématiques Département Mécanique Département Physique

UFR Sciences et Techniques des Activités Physiques et Sportives Observatoire des Sciences de l’Univers de Lyon

Polytech Lyon

Ecole Supérieure de Chimie Physique Electronique Institut Universitaire de Technologie de Lyon 1 Ecole Supérieure du Professorat et de l’Education Institut de Science Financière et d'Assurances

Directeur : M. F. DE MARCHI

Directeur : M. le Professeur F. THEVENARD Directeur : Mme C. FELIX

Directeur : M. Hassan HAMMOURI

Directeur : M. le Professeur S. AKKOUCHE

Directeur : M. le Professeur G. TOMANOV

Directeur : M. le Professeur H. BEN HADID Directeur : M. le Professeur J-C PLENET

Directeur : M. Y.VANPOULLE

Directeur : M. B. GUIDERDONI Directeur : M. le Professeur E.PERRIN Directeur : M. G. PIGNAULT

Directeur : M. le Professeur C. VITON

Directeur : M. le Professeur A. MOUGNIOTTE Directeur : M. N. LEBOISNE

(4)

REMERCIEMENTS

Ce projet de recherche de doctorat a été réalisé eu sein de l’Institut de Recherches sur la Catalyse et l’Environnement de Lyon », dirigé à mon arrivé par Monsieur Michel LACROIX et puis Madame Catherine PINEL, en collaboration avec le département de Catalyse par les Sulfures, dirigé par Madame Magalie ROY-AUBERGER, Direction Catalyse et Séparation, l’IFP Energies Nouvelles. Je souhaiterais exprimer mes reconnaissances aux nombreuses personnes qui m’ont aidé dans ma vie professionnelle et personnelle pendant mes trois ans de thèse.

Tout d’abord, je voudrais adresser mes remerciements sincères à M. Michel LACROIX, Mme. Catherine PINEL et Mme. Magalie ROY-AUBERGER pour m’avoir accueilli à leur laboratoire. Je remercie vivement Monsieur Christophe GEANTET, Directeur de Recherches au CNRS, Vice-président de l’IRCELYON, en tant que le directeur de thèse, pour avoir suivi, dirigé ma thèse et m’avoir toujours donné des conseils scientifiques précieux dans le domaine de catalyse et de génie chimique pour avancer mes travaux de recherche. Je te remercie, Christophe, de m’avoir toujours écouté avec ton patience et m’avoir aidé dans ma vie professionnelle et personnelle. Je te remercie également pour les moments sympathiques et les supports que tu m’as consacré aux congrès GeCat (à l’Obernai) et MACS VII (au Pays-Bas).

Mes remerciements très chaleureux sont certainement adressés à Madame Mélaz TAYAKOUT, Professeure de l’Université de Lyon 1, Chercheuse au Laboratoire d'Automatique et de Génie des Procédés, pour m’avoir encadré avec tous ses enthousiasmes et ses souries malgré son emploi surchargé. Elle m’a apporté ses soutiens scientifiques de très appréciés, particulièrement dans le domaine de génie de procédés, la thermodynamique, la cinétique réactionnelle et également les calculs mathématiques en Matlab. Sans elle, la partie de la modélisation cinétique qui est très importante de ma thèse ne pouvait pas être réalisée avec succès.

Je souhaite exprimer ma gratitude à Monsieur Gerhard PIRNGRUBER, Ingénieur de Recherches à l’IFP Energies Nouvelles, pour avoir co-encadré la thèse. Avec ses excellentes compétences professionnelles en catalyse et génie chimique, il m’a donné des conseils et des discussions très précieuses pour l’exploitation des résultats. Rigoureusement mais avec beaucoup d’enthousiasme et de passion, il m’a aidé à avancer ma thèse et à améliorer la qualité de mes publications. Je le remercie également pour ses soutiens à ma présentation au Pays Bas.

Je n’oublie pas remercier très sincèrement Monsieur Fabien CHAINET, Ingénieur de Recherches à l’IFP Energies Nouvelles, pour avoir co-encadré la thèse et m’avoir aidé à découvrir la partie analytique de ma thèse. Cette partie, qui ne connait pas beaucoup de la chance, mais avec sa grande

(5)

gentillesse et son enthousiasme, nous avons réussi de gagner assez de résultats. Je remercie également

à Florian ALBRIEUX, qui a joint à cette partie dans la 3ème_{année de ma thèse, pour nos discussions}

aimables sur les résultats de FT-ICR/MS et d’avoir corrigé le dernier chapitre de ma thèse.

Je tiens à remercier Madame Sylvette BRUNET, Chercheuse à l’Institut de Chimie des Milieux et Matériaux de Poitiers, et Monsieur Joris THYBAUT, Professeur de l’Université de Ghent, Belgique, pour avoir accepté de juger ma thèse et d’en être rapporteurs auprès de l’Université Claude Bernard Lyon 1, ainsi que Monsieur Frédéric AUBRIET, Professeur de l’Université de Lorraine, pour avoir accepté d’être l’examinateur de ma thèse, et Madame Anne GIROIR-FENDLER, Professeure de l’Université Claude Bernard Lyon 1, pour m’avoir fait l’honneur de présider le jury.

Mes grandes gratitudes sont aussi adressées à Monsieur Michel VRINAT, Directeur de Recherches Emérite au CNRS, et Monsieur Pascal RAYBAUD, Ingénieur de Recherches à l’IFP Energies Nouvelles, pour m’avoir donné des conseils et des discussions fructueuses sur la partie cinétique, l’histoire de sites catalytiques et l’adsorption. Je remercie également à Pavel AFANASIEV pour les calculs des charges moléculaires qu’il a pu me faire et surtout pour sa grande gentillesse.

Je souhaite remercier sincèrement à Chantal LORENTZ, responsable du service d’analyse GCxGC, Emmanuel LECLERC, Ingénieur technicien administratif à l’IRCELYON, pour leurs disponibilités constantes tout au long de ma thèse afin de mettre en route les appareillages, le réacteur d’autoclave et le pilote, me former leur fonctionnement et m’aider à résoudre les problèmes. Je remercie surtout à Chantal et Emmanuel pour leur amitié, pour les moments très sympas et relaxants.

Ce travail n'aurait pu aboutir sans l'aide de Mimoun AOUINE, Responsable du service d’analyse Microscopie, Laurence MASSIN, Ingénieure au service de la Spectroscopie Photoélectrons X, Pascale MASCUNAN et Noëlle CRISTIN, Responsables du service d’analyses texturales et élémentaires de catalyseurs. J’aimerais exprimer toutes mes gratitudes à vous pour m’avoir aidé à réaliser les manipulations ainsi qu’à me former les traitements de résultats. Je n’oublie pas remercier Anne-Marie GREZAUD, Marie-Laure VENDITTI, Narayman EL JERRARI, Géraldine CHAPUIS, Christine BABOLAT au Service Administratif de l’IRCELYON pour leur disponibilité et leur bonne humeur. Je profite également ma thèse pour remercier Dorothée LAURENTI, Chargée de Recherches de l’IRCELYON, mon encadrant de stage de Master, pour sa grande gentillesse et ses soutiens pendant mon stage et ma thèse, pour avoir assisté dans mes premiers pas dans le monde de la recherche scientifique, et pour m’avoir donné la passion de la faire.

Ces travaux de thèse ont été réalisés en collaboration avec les trois laboratoires de l’IFP Energies Nouvelles que je souhaite remercier: la spectrométrie de masse, l'infrarouge et la chromatographie. Un énorme merci est adressé à Julie MARIN pour toutes les manipulations de la préparation et de la sulfuration de catalyseurs, surtout pour son amabilité et son amitié. Je remercie de tout mon cœur Lyes

(6)

ASSAM et Jérôme CAPUANO pour m’avoir formé avec tous leurs enthousiasmes les manipulations et le traitement des résultats FT-ICR/MS, GC-NCD et GCxGC-NCD. Je remercie également Laurent LEMAITRE, au laboratoire de Spectroscopie, pour les analyses IR(CO) qu’il a pu me faire. Je remercie tout particulièrement mes collègues : Aurélia, Yohann, Christophe, Patrick et Sophie au laboratoire de la chromatographie en phase gazeuse pour m’avoir accueilli au sein du laboratoire. Je voudrais exprimer mes reconnaissances de tout mon cœur à mon cher parrain, Patrick GAUTSCHI, Mme. Hoang-Mai NGUYEN et Mme. Kim Ngoc LE, à l’Association de l’Ecole Sauvage, pour vos soutiens depuis que j’étais au lycée au Vietnam, pour m’avoir toujours fait confiance et suivi mes études en France. Je profite cette occasion pour remercier très chaleureusement « Light Your Hope Scholarship », Mme. Thuy Van NGUYEN et mes amis pour leurs supports pendant mes études universitaires au Vietnam et pour m’avoir donné des encouragements pendant mes trois ans de thèse. Je tiens également à adresser mes remerciements à mes collègues : Barbara, Luc et Tim dans l’équipe de la modélisation pour m’avoir aidé à sortir les problèmes mathématiques. Un grand merci à David, Zeré, Léon, Kathy, Barbara (elle est aussi mon professeure d’anglais), Titiya, Kubra, Eddy, Géraldine, Pierre et my honey Camila, ceux qui ont à un moment donné partagé avec moi le bureau. Un énorme merci à Thanh-Son et Ngoc-Quynh pour m’avoir toujours supporté dans ma vie professionnelle et personnelle. Je remercie également à mes amis vietnamiens : Nhung, Thanh Huyen, Son, Chuc, Quan, Nam… qui sont toujours à côté de moi. Merci à Nelly et Elodie avec qui j’ai eu les moments très sympas au Pays Bas ; Zoé avec qui j’ai partagé des bons moments pendant les journées et les stages de l’IFP ; Svétan pour les moments inoubliables au Minneapolis ; Florina qui est my lunch-mate ; Pedro (je n’ai rien pour parler de toi sauf crazy boy), Benoit, Lis, Ruben, Mattéo, Junjie, Maxime, Camella, Aziz, Caroline. Merci à vous tous pour avoir partagé des joies, des souvenirs inoubliables pendant mes trois ans de thèse.

Mes remerciements de tout mon cœur sont adressés à ma grand-mère, mon grand-père, mes sœurs, mon petit frère, mes tantes, qui m’ont soutenu mes études.

Je dédie cette thèse à mes chers parents qui tiennent une place immense dans mon cœur, qui sont des héros dans mes yeux, qui m’ont supporté avec leur amour pour tous les moments de ma vie.

(7)

RESUME :

L'objectif de la thèse est d'identifier les effets de l'acidité de catalyseurs sulfures supportés en hydrodésazotation (HDN) à l’aide d’un modèle cinétique.

Ce modèle cinétique de type Langmuir-Hinshelwood, intègre le transfert de masse liquide-vapeur, et est utilisé pour analyser les données cinétiques de l’HDN de la quinoléine et de l’indole sur NiMo(P)/Al2O3 et

NiMo(P)/ASA (silice alumine). Les résultats de la modélisation cinétique montrent que le NiMo(P)/ASA favorise l'hydrogénation du 1,2,3,4-tétrahydroquinoléine en decahydroquinoléine, qui est l’étape limitante. Cependant, un effet de promotion du NiMo(P)/ASA pour les étapes d'hydrogénation de l’HDN de l'indole n'est pas mis en évidence. En plus, le NiMo(P)/ASA favorise fortement les réactions d’élimination de l’atome d’azote. Les composés azotés s’adsorbent plus fortement sur NiMo(P)/ASA. La caractérisation par spectroscopie infrarouge de CO suggère que ces résultats pourraient être liés à la modification des propriétés électroniques de la phase NiMoS due à l'acidité plus élevée de l'ASA.

L’HDN d'un mélange de Straight Run et Coker Gazole suivie par FT-ICR/MS permet de suivre la conversion de molécules azotées basiques et non basiques et de comparer la réactivité de ces composés. L'HDN des composés neutres est inhibée par une adsorption forte des composés basiques. Les composés de type carbazole et quinoléine sont les plus réfractaires. Les composés de type benzocarbazoles sont plus réactives que les carbazoles. Les composés de courtes chaines d’alkyles sont plus réactifs que celles de longues chaines d’alkyles. L’activité intrinsèque pour l’HDN du NiMo(P)/ASA est plus importante que le NiMo(P)/Al2O3. La distribution

des composés azotés dans les effluents entre les catalyseurs est similaire, donc la discrimination de cinétique réactionnelle est difficile.

ABSTRACT

The objective of this thesis is to discriminate support acidity effects of sulfide catalysts in hydrodenitrogenation (HDN) reactions with an advanced kinetic model.

Kinetic data obtained from quinoline and indole HDN, over NiMo(P)/Al2O3 and NiMo(P)/ASA (silica alumina)

catalysts were analyzed by a Langmuir-Hinshelwood kinetic model, including liquid-vapor mass transfer, in order to estimate kinetic and adsorption parameters. Kinetic modeling indicates that the NiMo(P)/ASA favors the hydrogenation of 1,2,3,4-tetrahydroquinoline into decahydroquinoline, which is the rate limiting step of quinoline HDN. However, a promoting effect of the NiMo(P)/ASA in hydrogenation steps of indole HDN is not clearly evidenced. In quinoline and indole HDN, the NiMo(P)/ASA shows a strong promoting effect in N-removal reactions. Nitrogen compounds adsorb more strongly over NiMo(P)/ASA. Characterization by Infra-Red spectroscopy of CO suggests that these results may be related to the modification of the electronic properties of promoted NiMoS phase due to higher acidity of ASA.

The HDN of a Straight Run and Coker Gas Oil mixture followed by FT-ICR/MS describes the conversion of basic and non basic N-compounds and compares HDN reactivity of these compounds. The HDN of neutral compounds is inhibited by stronger adsorption of basic compounds. Carbazole-type and quinoline-type compounds are refractory. Benzocarbazole-type compounds are more reactive than carbazoles ones. Short-alkyl chain molecules are more reactive than long-alkyl chain ones towards hydrogenation. The NiMo(P)/ASA is more intrinsically active for HDN than the NiMo(P)/Al2O3. The N-compounds distribution in the effluents is not

radically different between the two catalysts, thus the discrimination of reaction kinetic is difficult.

KEYWORDS: hydrodenitrogenation, quinoline, indole, Coker Gas Oil, kinetic modeling, sulfide catalysts,

adsorption

ADRESSES OF LABORATORIES:

- Institute de Recherches sur la Catalyse et l’Environnement de Lyon, CNRS- Université de Lyon 1, 02 avenue Albert Einstein, 69100 Villeurbanne, France

- IFP Energies Nouvelles, Etablissement de Lyon, BP3, Rond-point de l’échangeur de Solaize, 69360 Solaize, France

(8)

LIST OF TABLES

Table 1-1: pKa and proton affinity (PA) values of some nitrogen model compounds 8,10–14 ... 12

Table 1-2: Summary of the reactivity order for nitrogen compounds towards HDN ... 25

Table 1-3: Kinetic model utilized for real feed hydrotreatment ... 28

Table 1-4: Effect of support acidity on HDN activity ... 30

Table 2-1: Elemental composition of catalysts ... 48

Table 2-2: Textural properties of the catalysts ... 49

Table 2-3: Activity in toluene hydrogenation and cyclohexane isomerization... 52

Table 2-4: Binding energies (eV) of atoms on both catalysts in XPS spectra ... 53

Table 2-5: Atomic ratios of elements from XPS and ICP quantitative analysis ... 53

Table 2-6: Quantification of NiMoS active phase in the catalysts ... 57

Table 2-7: Distribution of CO adsorbed species from the peak decomposition of bands IR(CO) ... 61

Table 3-1: Comparison of the composition of samples taken at hot and cold conditions ... 71

Table 3-2: Volatility and L-V equilibrium constants (θi) of PB, PCH, PCHE, Quinoline, NH3, H2S, H2 and solvents at 340, 350, 360°C and 7 MPa (Simulation by ProSim) ... 72

Table 3-3: Total porous volume, BET surface area and carbon content of used catalysts ... 80

Table 3-4: Deactivation ratio of the catalysts after quinoline HDN test ... 80

Table 3-5: Adsorption parameters at 350°C of nitrogen compound a_{... 92}

Table 3-6: Apparent rate constants, effective rate constants at 350°C and activation energies of (de)hydrogenation reactions and their confidence intervals a_{... 96}

Table 3-7: Variation of ratios r6/(r4-r5) during the quinoline HDN at 350°C, 7 MPa and 1 wt % of quinoline ... 97

Table 3-8: Apparent rate constants, effective rate constants at 350°C and activation energies of denitrogenation reactions and hydrogenation of PCHE and their confident intervals b_{... 98}

Table 3-9: Intrinsic rate constants (apparent rate constants calculated per 1 mmol NiMoS) at 350°C of non-equilibrated reactions ... 99

Table 3-10: L-V mass transfer coefficient kLa ... 102

Table 4-1: Volatilities and L-V equilibrium constants (θi) of indole and its products at different temperatures and 7MPa, estimated by ProSim ... 116

(13)

Table 4-2: Nitrogen mass balance of the test indole HDN over NiMo(P)/Al2O3, 360oC, 1 wt% indole

... 117

Table 4-3: Nitrogen mass balance of the test indole HDN over NiMo(P)/ASA, 360o_{C, 1 wt% indole 117} Table 4-4: Characterization of the used catalysts after indole HDN ... 121

Table 4-5: Deactivation ratio of the catalysts after indole HDN test at 350°C ... 122

Table 4-6: Adsorption enthalpies and adsorption constants of indole and its products ... 132

Table 4-7: Apparent and effective rate constants at 350°C, activation energies of certain elementary steps of the first reaction path of indole HDN ... 134

Table 4-8: Apparent and effective rate constants at 350°C, activation energies of certain elementary steps of the second reaction path of indole HDN ... 135

Table 4-9: Intrinsic apparent rate constants at 350o_{C (calculated per 1 mmol of NiMoS sites) of indole} HDN over both catalysts (mmol.l-1_.s-1_{/mmol NiMoS) ... 137}

Table 4-10: Comparison of the support acidity effects on the HDN of quinoline and indole ... 142

Table 4-11: Data for calculating KS1/KS2 ratio: (a) over NiMo(P)/Al2O3, (b) over NiMo(P)/ASA ... 146

Table 4-12: Comparison of apparent adsorption constants of quinoline, indole and theirs products relatively to the m-xylene+squalane solvent (Kint(i)/(KS1.CS1)), at 350°C, over the two catalysts ... 147

Table 5-1: GCxGC-NCD analysis method for Gas oil mixture... 165

Table 5-2: Molecular structures of basic N-compounds and their corresponding Double Bond Equivalent (DBE) (numbers in brackets and in italic is experimental values of pKa for non-alkylated compounds 46,47_{) ... 168}

Table 5-3: Molecular structures of non-basic N-compounds and their corresponding Double Bond Equivalent (DBE) (numbers in brackets and in italic is experimental values of pKa for non-alkylated compounds 47) ... 170

Table 5-4: Properties of straight run gas oil, coker gas oil and the gas oil mixture ... 171

Table 5-5: Distribution of carbon number of each DBE in (a) basic and (b) neutral classes ... 178

Table 5-6: Reaction order and apparent rate constants of HDS reactions ... 182

Table 5-7: Reaction order and apparent rate constants of HDN reactions ... 182

Table 5-8: Apparent activation energies of the gas oil HDS, HDN over both catalysts ... 185

Table 5-9: Determination of the loss of HDS and HDN activity for 2 catalysts ... 185

(14)

LIST OF FIGURES

Figure 1-1: Total European refined products demand in 2010 and 2030 1_{... 10}

Figure 1-2: Several model nitrogen compounds in petroleum fractions 2–7_{... 11}

Figure 1-3: GCxGC-NCD image of diesel fraction 3_{... 13}

Figure 1-4: GCxGC-HT-NCD chromatograms of the straight-run VGO (neutral (A) and basic (B) fractions) and of the direct coal liquefaction VGO (neutral (C) and basic (D) fractions) 18 ... 14

Figure 1-5: Polyheteroatom compounds in heavy petroleum cuts 6,25_{... 15}

Figure 1-6: Dependence of hydrocracking conversion on total nitrogen content in feed ... 16

Figure 1-7: Reaction pathway of pyridine HDN 47_{... 19}

Figure 1-8: Reaction pathway and rate constants of quinoline HDN (reaction rate constants from Satterfield and Yang 79_{, reaction scheme from}80–82_{) ... 20}

Figure 1-9: Reaction pathways of acridine HDN 84_{... 21}

Figure 1-10: Reaction pathways of 5,6-benzoquinoline HDN 65_{... 22}

Figure 1-11: Reaction pathways of indole HDN 67_{... 23}

Figure 1-12: Reaction scheme of carbazole HDN 87 ... 24

Figure 1-13: tetrahydrocycloheptacarbazole 103_{... 26}

Figure 1-14: TEM (Transmission electron microscopy) image of an active phase of Co(Ni)MoS/Al2O3 (left). Molecular model of one Co(Ni)MoS nano-layer with a two-dimensional morphology (centre). Bulk MoS2 structure with infinite stacking of MoS2 layers (right) 119 ... 29

Figure 1-15: Distribution of Ni in sulfided NiMo/Al2O3 catalyst: as active sites on the MoS2 edges (NiMoS phase); as segregated Ni3S2, and as Ni2+ ions in the support lattice 119 ... 29

Figure 1-16: Participation of acid sites in the HDN of methyl-cyclohexylamine 139_{... 31}

Figure 1-17: The xylene formation route in 2,6-dimethylaniline decomposition ... 31

Figure 1-18: Variation of ν(CO) wavenumber of CO adsorbed on MoS2 dispersed in the β-zeolite of various acidities; the number of acid sites measured by IR and hydrogenation activities. The number after β symbole is the Si/Al ratio of the catalyst 143_{... 32}

Figure 2-1: Nitrogen isotherm adsorption/desorption curve of the catalysts ... 49

Figure 2-2: BJH Desorption dV/dD as function of pore diameter of the catalysts ... 50

(15)

Figure 2-4: Spectra decomposition of Mo 3d of NiMo(P)/Al2O3 (a) and NiMo(P)/ASA (b) ... 54

Figure 2-5: Spectra decomposition of S 2p of NiMo(P)/Al2O3 (a) and NiMo(P)/ASA (b) ... 55

Figure 2-6: Spectra decomposition of Ni 2p of NiMo(P)/Al2O3 (a) and NiMo(P)/ASA (b) ... 56

Figure 2-7: Distribution of Mo (a), S (b) and Ni (c) species obtained from XPS ... 57

Figure 2-8: Schematic representation of the chemisorption of CO over a sulfide catalyst ... 58

Figure 2-9: Subtracted IR spectra in the region of interaction of CO with NiMo(P)/Al2O3 ... 59

Figure 2-10: Subtracted IR spectra in the region of interaction of CO with NiMo(P)/ASA ... 60

Figure 2-11: IR spectra of CO adsorbed on the sulfide catalysts: (a) after the first pulse of CO and (b) at saturation of the sulfide phase with CO. The distribution of the band position in the spectra at saturation of CO is obtained by peak decomposition. ... 61

Figure 2-12: TEM Images of NiMo(P)/Al2O3 (left) and NiMo(P)/ASA (right) ... 63

Figure 2-13: Distribution of length of MoS2 nanosheets in the two 2 catalysts NiMo(P)/Al2O3 (left) and NiMo(P)/ASA (right) ... 63

Figure 3-1: Batch reactor for quinoline HDN test ... 69

Figure 3-2: Concentration of components at hot condition and after corrected by evaporation ... 73

Figure 3-3: Reaction network of quinoline HDN ... 73

Figure 3-4: ln(Co/C) (C is the summary of Q, 14THQ, 58THQ concentration) (a) and HDN conversion (b) versus reaction time obtained from 3 tests at 340, 350 and 360°C, at 1.5 wt% of quinoline as initial concentration of quinoline, over NiMo(P)/Al2O3 ... 75

Figure 3-5: ln(Co/C) (C= Q+14THQ+58THQ) versus reaction times, over NiMo(P)/Al2O3 (a, b) and NiMo(P)/ASA (c, d), at 2 initial concentrations of quinoline: 1 (a, c) and 2 wt% (b, d) ... 76

Figure 3-6: ln(Co/C) (C = Q+58THQ+14THQ) (a) and HDN Conversion (b) as function of products of reaction time with volume of catalysts, of catalytic tests at 350°C, 7MPa, 1 wt% of quinoline ... 77

Figure 3-7: Logarithm values of pseudo-first-rate constant of the disappearance of Quinoline+14THQ+58THQ, as function of 1/T plot. The slope obtained is the value of Ea/R ... 78

Figure 3-8: The yield of OPA (a), PB (b), DHQ (c), PCH (d) as function of HYD conversion of catalytic tests at 350°C, 7MPa, 1 wt% of quinoline, over NiMo(P)/Al2O3 (red color) and NiMo(P)/ASA (blue color) ... 78

Figure 3-9: Liquid-Vapor mass transfer scheme in batch reactor 1_{... 85}

(16)

Figure 3-11: Reaction pathways of quinoline HDN for kinetic modeling 1 ... 88 Figure 3-12: Comparison of simulation results (continuous line) and experimental data (points) of 3

tests at 350°C at 1 wt% (a), 1.5 wt% (b) and 2 wt% (c) of quinoline, over NiMo(P)/Al2O3 ... 89

Figure 3-13: Comparison of simulation results (continuous line) and experimental data (points) of 3 tests at 350°C at 1 wt% (a), 1.5 wt% (b) and 2 wt% (c) of quinoline, over NiMo(P)/ASA ... 90 Figure 3-14: Comparison of HDN conversion calculated by kinetic model (continuous line) and experimental HDN conversion (points) of 2 tests at 340°C (a) and 360°C (b), at 1 wt% of quinoline, over both catalysts. ... 91 Figure 3-15: Correlation between pKa and adsorption constants of nitrogen compounds ... 94

Figure 3-16: Plot of Ki/(1+∑KjCj,liq)2 values of the rate determining step (14THQ→DHQ) over both

catalysts as function of reaction times, at iso-volume ... 101

Figure 3-17: Conversion of dodecylamine over NiMo(P)/Al2O3 and NiMo(P)/ASA ... 102

Figure 3-18: Comparison of simulation results (continuous line) and experimental data (points) of additional test for the validation of kinetic model ... 103

Figure 4-1: Reaction pathways of indole HDN 4_{... 113}

Figure 4-2: Concentrations of products after 2h of reaction, at 350°C, 0.75 wt% of indole, over

NiMo(P)/Al2O3, at hot and cold sampling ... 115

Figure 4-3: Concentrations of products after 1.5h of reaction, at 360°C, 0.75 wt% of indole, over NiMo(P)/ASA, at hot and cold sampling ... 115 Figure 4-4: GC-NCD Chromatogram of liquid sample obtained at 30 min, 360°C, over NiMo(P)/ASA, 1 wt% indole ... 118

Figure 4-5: Formation of light by-products of indole HDN 1_{... 119}

Figure 4-6: Semi-quantification of by-products in liquid phase during the tests over NiMo(P)/ASA, at 340°C and 360°C, 1 wt% indole ... 120

Figure 4-7: ln(Co/C) with C=[IND]+[HIN] versus reaction time obtained from catalytic tests at

different temperatures, 0.5 wt% indole, over NiMo(P)/Al2O3 (a) and NiMo(P)/ASA (b) ... 123

Figure 4-8: Plot of logarithm values of pseudo-first-rate constant of the disappearance of indole + HIN obtained from the tests at 0.5 wt% indole, as function of 1/T. The slope obtained is the value of

Ea/R ... 123

Figure 4-9: ln(Co/C) with C=[IND]+[HIN] versus reaction time obtained from catalytic tests at

(17)

Figure 4-10: Compare the HDN conversion of indole over the two catalysts, at 350°C, 7 MPa, in the test of (a) 0.5 wt% and (b) 1 wt% of indole ... 125 Figure 4-11: Selectivity to products comparison of the two catalysts in the test of indole HDN, at 350°C, 7MPa and 1 wt% indole, (a) Indole, (b) o-Ethylaniline, (c) ethylbenzene, (d) ethylcyclohexane ... 126 Figure 4-12: Reaction scheme of indole HDN for kinetic modeling ... 127 Figure 4-13: Simulation results (continuous line) and experimental data (points) of 3 tests at 350°C,

over NiMo(P)/Al2O3, at 0.5 wt% (a), 0.75 wt% (b) and 1 wt% (c) of indole ... 129

Figure 4-14: Simulation results (continuous line) and experimental data (points) of 3 tests at 350°C, over NiMo(P)/ASA, at 0.5 wt% (a), 0.75 wt% (b) and 1 wt% (c) of indole... 130

Figure 4-15: L-V thermodynamic equilibrium constants of indole, EB, ECH and NH3, calculated by

the kinetic model, at 340o_{C and 7 MPa. ... 131}

Figure 4-16: [HIN]/[IND] ratio at 350°C, 1 wt% indole over (a) NiMo(P)/Al2O3 and (b)

NiMo(P)/ASA, determined by experimental data and kinetic modeling ... 133

Figure 4-17: Plot of Ki/(1+∑KjCj,liq)2 values of the rate determining steps (HIN→OHIN and

OEA→ECHA) over both catalysts as function of reaction times, of the test at 1 wt% (a) and 0.5 wt% (b) of indole ... 138

Figure 4-18: By-product formation calculated by the kinetic model, over NiMo(P)/Al2O3 (a) and

NiMo(P)/ASA (b), at 350°C and 7 MPa ... 140 Figure 4-19: Comparison HDN reactivity of indole and quinoline (C = [Q]+[58THQ]+[14THQ] for quinoline HDN and C = [IND]+[HIN] for indole HDN) ... 142 Figure 4-20: Disappearance rate of indole + dihydroindole in the two different solvents, over

NiMo(P)/Al2O3 (a) and NiMo(P)/ASA (b), 0.5 wt% of indole, at 350°C ... 144

Figure 4-21: Reaction scheme of the disappearance of indole and dihydroindole ... 145 Figure 4-22: Relative order of apparent adsorption constants of nitrogen compounds, correlated with pKa values ... 148 Figure 4-23: HDN conversion of quinoline in the absence (Q test) and the presence of indole (Q+IND

tests), and indole & OEA concentrations , (a) over NiMo(P)/Al2O3, (b) over NiMo(P)/ASA, at 350°C, 7

MPa ... 149 Figure 4-24: HDN conversion of indole in the absence (IND test) and the presence of quinoline (Q+IND tests), and Q + 14THQ +58THQ & DHQ concentrations obtained from, (a) over

(18)

Figure 5-1: Synoptic diagram of micropilot ... 161

Figure 5-2: Protocol of catalytic tests in continuous fixed-bed reactor ... 162

Figure 5-3: Principle of comprehensive gas chromatography 38,39_{... 164}

Figure 5-4: Diagram of the FT/ICR-MS (Thermo Scientific LTQ-FT-Ultra) 9_{... 166}

Figure 5-5: Ionization mechanism of acridine (a) and carbazole (b) 48_{... 170}

Figure 5-6: Compositional analysis of sulfur in gas oil mixture ... 171

Figure 5-7: Distribution of hydrocarbon families in gas oil mixture analyzed by GCxGC-FID and reconstructed simulated distillation ... 172

Figure 5-8: GCxGC-NCD chromatogram of gas oil mixture ... 173

Figure 5-9: Distribution of N-compound families from GCxGC-NCD analysis ... 174

Figure 5-10: ESI(+) FT/ICR-MS raw spectrum for gas oil mixture ... 175

Figure 5-11: ESI(-) FT/ICR-MS raw spectrum for gas oil mixture ... 175

Figure 5-12: Diagram for the relative abundance of N1 basic compounds as function of DBE and carbon number in the gas oil mixture... 176

Figure 5-13: Diagram for the relative abundance of neutral N1 compounds as function of DBE and carbon number in the gas oil mixture... 176

Figure 5-14: Concentration of representative families by DBE in basic class ... 177

Figure 5-15: Concentration of representative families by DBE in neutral class ... 177

Figure 5-16: Comparison of HDS conversions of gas oil tests at 350, 360, 370°C, as function of times on stream of gas oil tests over NiMo(P)/Al2O3 ... 179

Figure 5-17: Comparison of HDN conversions of gas oil tests at 350, 360, 370°C, as function of times on stream of gas oil tests over NiMo(P)/Al2O3 ... 179

Figure 5-18: Determination of reaction order and apparent rate constants of HDS (a) and HDN (b) reaction, over NiMo(P)/Al2O3, at 360°C ... 181

Figure 5-19: Comparison of HDS (a) and HDN (b) conversions between the 2 catalysts in the tests of gas oil mixture at 360°C ... 183

Figure 5-20: Determination of apparent activation energies of gas oil (a) HDS and (b) HDN, over the 2 catalysts ... 184

Figure 5-21: DBE modification during the HDN of model molecules ... 187

(19)

Figure 5-23: Total and basic nitrogen content in gas oil feed and hydrotreated effluents ... 189 Figure 5-24: Relative percentage of basic nitrogen content in the feed and effluents ... 190

Figure 5-25: Conversion of N1 and polyheteroatom basic families over both catalysts ... 191

Figure 5-26: Distribution of DBE and carbon number of N1S1 basic family in the feed and the

effluents, (a) 76% HDN conversion over NiMo(P)/Al2O3, (b) 71% HDN conversion over NiMo(P)/ASA

... 191

Figure 5-27: Examples of N1S1 and N1O1 polyheteroatom compound conversion ... 192

Figure 5-28: Pseudo concentration of each basic N-family (or each DBE) in effluents from the test

over (a) NiMo(P)/Al2O3 and (b) NiMo(P)/ASA ... 193

Figure 5-29: Relative percentage of basic nitrogen families, in the feed and in the effluents at 80% HDN conversion, over both catalysts ... 194 Figure 5-30: Pseudo concentration of each neutral N-family (or each DBE) in effluents from the tests

over (a) NiMo(P)/Al2O3 and (b) NiMo(P)/ASA ... 195

Figure 5-31 : Relative percentage of neutral nitrogen families, in the feed and in the effluents at 80% HDN conversion, over both catalysts ... 196 Figure 5-32: Carbon number distribution curves of total nitrogen in the effluents as compared to that

in the feed, (a) over NiMo(P)/Al2O3 and (b) over NiMo(P)/ASA ... 197

Figure 5-33: Pseudo-concentration by carbon number of basic nitrogen (a, b) and neutral nitrogen (c,

d) in the effluents as compared to that in the feed, over NiMo(P)/Al2O3 (a, c) and over NiMo(P)/ASA

(b, d) ... 198 Figure 5-34: Pseudo-concentration by carbon number of DBE-based basic nitrogen families: (a, b) DBE = 4, (c, d) DBE = 7, (e, f) DBE = 10 in the effluents and in the feed ... 200 Figure 5-35: Comparison of pseudo-concentration by carbon number of DBE-based basic nitrogen families: (a) DBE = 4, (b) DBE = 7, (c) DBE = 10 in the effluents at 80% HDN conversion over both catalysts and in the feed ... 202 Figure 5-36: Pseudo-concentration by carbon number of DBE-based neutral nitrogen families: (a, b) DBE = 6, (c, d) DBE = 9, (e, f) DBE = 12 in the effluents and in the feed ... 203 Figure 5-37:Pseudo-concentration of several alkylated derivatives of pyridines/anilines as function of HDN conversion, (a) C6-PYR or C5-ANI, (b) C8-PYR or C7-ANI, (c) C10-PYR or C9-ANI, (d) C12-PYR or C11-ANI; green squared point is for pseudo-concentration of corresponding alkylated molecules in the feed. ... 205 Figure 5-38 : Conversion of C6-quinolines into C9-anilines ... 205

(20)

Figure 5-39 : Conversion of specific alkylated quinoline and acridines-type compounds as function of total HDN conversion, (a, b) quinolines; (c, d) acridines ... 206 Figure 5-40: Pseudo concentrations by DBE distribution of basic nitrogen C15 (a), C20 (b) and C26

(c) in the feed and the effluents of the tests over NiMo(P)/Al2O3 ... 207

Figure 5-41: Hydrogenation reactions of basic C15 and C26 molecules ... 208 Figure 5-42: Scheme of the main reaction pathway of tetrahydroacridine and carbazole associated with DBE, intermediates and products ... 210

(21)

APPENDICES

Appendix 1: Bibliography studies on the effects of hydrogen partial pressure, partial pressure

of H2S and temperatures on the HDN reactions ... 222

Appendix 2A : Hydrogenation of toluene ... 225

Appendix 2B : Isomerization of cyclohexane ... 226

Appendix 2C : Infra-Red Spectra of CO over alumina and silica-alumina supports ... 227

Appendix 3A: Product analysis of quinoline HDN by GC-FID and GCxGC-MS ... 230

Appendix 3B: Comparison of simulation results (continuous line) and experimental data (points) of 3 tests at 340°C, at 1 wt % (a), 1.5 wt % (b) and 2 wt % (c) of quinoline, over NiMo(P)/Al2O3 ... 233

Appendix 3C: Comparison of simulation results (continuous line) and experimental data (points) of 3 tests at 360°C, at 1 wt % (a), 1.5 wt % (b) and 2 wt % (c) of quinoline, over NiMo(P)/Al2O3 ... 234

Appendix 3D: Comparison of simulation results (continuous line) and experimental data (points) of 3 tests at 340°C, at 1 wt % (a), 1.5 wt % (b) and 2 wt % (c) of quinoline, over NiMo(P)/ASA ... 235

Appendix 3E: Comparison of simulation results (continuous line) and experimental data (points) of 3 tests at 360°C, at 1 wt % (a), 1.5 wt % (b) and 2 wt % (c) of quinoline, over NiMo(P)/ASA ... 236

Appendix 3F: Calculation of liquid-vapor mass transfer coefficient from empirical correlation, based on experimental parameters ... 237

Appendix 4A : Method of GC-FID and GC-NCD for analysis of indole and its products .... 239

Appendix 4B: FT-ICR/MS analyses of heavy by-products produced from indole HDN ... 240

Appendix 4C : Comparison of simulation results (continuous line) and experimental data (points) of 3 tests at 340°C, at 0.5 wt % (a), 0.75 wt % (b) and 1 wt % (c) of indole HDN, over NiMo(P)/Al2O3 ... 241

(22)

Appendix 4D : Comparison of simulation results (continuous line) and experimental data (points) of 3 tests at 360°C, at 0.5 wt % (a), 0.75 wt % (b) and 1 wt % (c) of indole HDN, over NiMo(P)/Al2O3 ... 242 Appendix 4E : Comparison of simulation results (continuous line) and experimental data (points) of 3 tests at 340°C, at 0.5 wt % (a), 0.75 wt % (b) and 1 wt % (c) of indole HDN, over NiMo(P)/ASA ... 243 Appendix 4F : Comparison of simulation results (continuous line) and experimental data (points) of 3 tests at 360°C, at 0.5 wt % (a), 0.75 wt % (b) and 1 wt % (c) of indole HDN, over NiMo(P)/ASA ... 244 Appendix 4G : HDN Conversion of indole HDN calculated by the kinetic model, over both catalysts, at 350oC, 0.5 wt% (a) and 1 wt % (b) of indole ... 245 Appendix 5A: Distribution of N1 and polyheteroatom families in the gas oil feed ... 246

Appendix 5B: Carbon number distribution of DBE-based basic and neutral families in the SRGC+CGO feed ... 247

Appendix 5C: Plot of HDS reaction rate to HDN reaction rate ratios (rHDS/rHDN) as function of temperature. ... 249 Appendix 5D: Conversion of polyheteroatom neutral families ... 250 Appendix 5E: Distribution of carbon number of total nitrogen in the effluents and in the feed

... 251

Appendix 5F: Distribution of carbon number of basic and neutral nitrogen in the effluents and in the feed ... 252 Appendix 5G: Comparison of pseudo-concentration by carbon number of DBE-based neutral nitrogen families: (a) DBE = 6, (b) DBE = 9, (c) DBE = 12 in the effluents at 80% HDN conversion over both catalysts and in the feed... 253 Appendix 5H: Conversions of different alkylated molecules of quinoline-type compounds .. 254 Appendix 5I: Conversions of different alkylated molecules of carbazole-type compounds ... 255 Appendix 5J: Pseudo-concentration by DBE distribution of neutral C15, C20 and C26 in the effluents and in the feed ... 256

(23)

NOMENCLATURES

Reactant, intermediates and products 14THQ: 1,2,3,4-tetrahydroquinoline 58THQ: 5,6,7,8-tetrahydroquinoline DHQ: decahydroquinoline OPA: o-propylaniline PB: propylbenzene PCH: propylcyclohexane PCHA: propyl-cyclohexylamine PCHE: propylcyclohexene Q: quinoline IND: indole HIN: 2,3-dihydroindole OHIN: octahydroindole OEA: ortho-ethylaniline ECHA: ethyl-cyclohexylamine EB: ethylbenzene ECHE: ethyl-cyclohexene ECH: ethyl-cyclohexane

PYR: pyridine or pyridine-type compounds ANI: aniline-type compounds

THQ: tetrahydroquinoline-type compounds ACR: acridine or acridine-type compounds CAR: carbazole or carbazole-type compounds 4,6-DMDBT: 4,6-dimethyl-dibenzothiophene Nomenclatures for analytical methods: BET : Brunauer-Emmett-Teller

DBE: Double Bond Equivalent ESI: electrospray ionization mode

GC-AED : Gas Chromatography coupled to Atomic Emission detector GC-FID: Gas Chromatography coupled to Flame Ionization Detector

(24)

GC-NCD: Gas Chromatography coupled by Nitrogen Chemiluminescence Detector GCxGC-NCD: Comprehensive Gas Chromatography coupled to Nitrogen

Chemiluminescence Detector KMD: Mass Kendrick Defect

NPD: Nitrogen Phosphorous Detector

NCD: Nitrogen Chemiluminescence Detector IR(CO): Infra-Red spectroscopy of adsorbed CO

ICP-OES: Inductively Coupled Plasma Optical Emission Spectroscopy

FT-ICR/MS: Fourier Transform Ion Cyclotron Resonance Mass Spectrometry SBET: specific surface area (m2.g-1)

TPV: total pore volume (ml.g-1)

TEM: Transmission Electron Microscopy XPS: X-ray Photoelectron Spectroscopy Others

ASA: amorphous silica alumina

CNDC: carbon number distribution curve CGO: Coker Gas Oil

CUS: coordinatively unsaturated sites DFT: Density Functional Theory DMDS: dimethyl disulfide FCC : fluid catalytic cracking HCK : hydrocracking

HDA : hydrodearomatization HDN: hydrodenitrogenation HDS : hydrodesulfurization LVE: liquid-vapor equilibrium

LHSV: Liquid Hourly Space Velocity, (volume of feed/volume of catalyst/h) P: pressure of reaction (kPa)

PA : proton affinity (kcal/mol)

pKa: logarithmic acid dissociation constant RO : ring opening

VGO: Vacuum Gas Oil SRGO: Straight Run Gas Oil

(25)

to: initial point of reaction

Mathematical parameters

a: exchange surface density (dm-1)

A, B: pre-exponential factors

: molar concentration of component i in liquid phase at equilibrium (mmol.l-1) : molar concentration of component i in liquid phase (mmol.l-1)

g i

C, : molar concentration of component i in gas phase (mmol.l

-1₎

total liq

C : total concentration of all components in liquid phase (mmol.l-1)

Co: initial concentration of quinoline or indole (mmol.l-1) Cs: concentration of solvents in liquid phase (mmol.l-1)

D: the least square of a summary of the difference between experimental and calculated

concentrations

H: Hessian matrix

J: Jacobian sensitive matrix

i

k : apparent rate constant (mmol.l-1_.s-1₎

ko: the pseudo-first rate constant (h-1)

app

k : apparent rate constant of HDS and HDN of the real feed

Ki: equilibrium adsorption constant of component i, relatively as compared to the adsorption

of solvents (l.mmol-1)

ki.Ki: effective rate constant (s-1)

eq

K : equilibrium constant of equilibrium reaction

int

i

K , int

s

K : intrinsic adsorption constant of component i and solvents, respectively

: mass transfer coefficient from gas-liquid interface to bulk liquid (dm.s-1)

: coefficient of L-V transfer (s-1)

kHYD: toluene hydrogenation activity (h-1) m/z: mass to charge ratio

n: reaction order of HDS and HDN of the real feed

: molar quantity of component i exchanged by L-V surface (mmol.s-1.dm-2)

ni: molar quantity of component i (mmol)

o Q

n : initial molar quantity of quinoline (mmol)

* ,liq i C liq i C_, L k a k_L V exchangeL i N

(26)

o INDOLE

n : initial molar quantity of indole (mmol)

N: number of experimental points

t: Student number

r4: reaction rate of the hydrogenation of 58THQ into DHQ (mmol.l-1.s-1) r5: reaction rate of the dehydrogenation of DHQ into 58THQ (mmol.l-1.s-1) r6: reaction rate of the hydrogenation of 14THQ into DHQ (mmol.l-1.s-1) r8: reaction rate of the ring opening of DHQ into PCHA (mmol.l-1.s-1) r9: reaction rate of the hydrogenation of OPA into PCHA (mmol.l-1.s-1) r10: reaction rate of the dehydrogenation of PCHA into OPA (mmol.l-1.s-1)

solid v i

r_, : volumetric rate of formation of component i on the catalytic sites (mmol.l-1.s-1)

Sexchange: surface through which the L-V transfer takes place (dm2)

T: temperature (Kelvin)

gas

V : volume of gas at reaction condition (l)

liq

V : volume of liquid at reaction condition (l)

cold liq

V : volume of liquid at normal (cold) condition (l)

Vsolid:solid volume of catalyst (l)

Vjj : inverse of Hessian matrix

X: conversion of toluene hydrogenation Y: conversion of cyclohexane isomerization

Greek letter

θi: liquid-vapor equilibrium constant of component i

i

M

: Volatility of component i

i

G

: fractional occupation of the molecule i on the catalytic sites

ΔTloss: temperature increase for evaluating deactivation level

2

V

: variance of the estimation

Ea: activation energy (kJ.mol-1) ∆Hads: adsorption enthalpy (kJ.mol-1)

(27)

Introduction générale

La croissance de la demande en carburant, le teneur importante en impuretés dans les pétroles bruts et le contrôle des émissions de gaz sont les principaux facteurs qui exigent l'amélioration de la performance des procédés de raffinage. À long terme, l'industrie pétrolière devra adapter aux changements dans la demande en carburant et la modification de la qualité de pétrole brut. Les procédés d'hydrotraitement et de valorisation des fractions lourdes sont de plus en plus nécessaires pour produire plus de carburants légers et propres. Les réactions d’hydrotraitement jouent deux rôles importants: (i) l'élimination du soufre et des composés aromatiques pour satisfaire les règles en qualité de carburant et en environnement; (ii) la purification des fractions pétrolières pour des procédés de conversion catalytiques en aval. L’implémentation de l’étape d’hydrotraitement avant les procédés de conversion permet d’éviter l’empoisonnement de catalyseurs dans ces dernières étapes et donc améliorer ses conversions.

L’utilisation de catalyseurs d’hydrodésazotation est de plus en plus importante due à la demande en valorisation des coupes pétrolières lourdes et les effets négatifs des composés azotés organiques dans les procédés de conversion. Ces composés peuvent provoquer l’empoisonnement de catalyseurs acides dans les procédés d’hydrocraquage ou de craquage catalytique, même à inférieure à 50 ppm d’azote. Ils réagissent également comme les inhibiteurs en hydrodésulfurisation et hydrodésaromatisation en raison de l’adsorption compétitive sur les sites catalytiques de ces composés. Les tentatives pour améliorer la formulation de catalyseurs d’hydrotraitement peuvent être réalisées via la modification de l’acidité du support de catalyseurs sulfures. Le design rationnel de catalyseur d’HDN demande une meilleure compréhension des effets de l’acidité de catalyseurs sur l’activité et la sélectivité. Des études cinétique de la réaction d’HDN est un moyen clé afin d’atteindre cette compréhension.

Les études compréhensives du mécanisme réactionnel sur la charge réelle est difficile due à la complexité du mélange. Par conséquent, la première option plus simple est d’utiliser les molécules modèles desquels le schéma réactionnel peut être étudié en détail. Le premier objectif de la thèse est de discriminer le rôle de l’acidité du support de catalyseurs sulfures à base de NiMo dans l’HDN des molécules modèles. Pour celui-ci, les deux catalyseurs d’acidité différente de support, le premier supporté sur γ-alumine (le catalyseur de référence) et le deuxième supporté sur silice-alumine amorphe (préparé par l’imprégnation à sec à l’IFP Energies Nouvelles) sont choisis. La quinoléine et l’indole, respectivement le composé basique et non basique, sont choisis pour notre étude. Les effets de l’acidité du support sont étudiés par la combinaison de résultats de caractérisations de catalyseurs et ceux de la modélisation cinétique avancée. Le rôle de l’acidité du support sur chaque étape élémentaire dans le schéma réactionnel, qui se compose de l’hydrogénation, l’ouverture de cycle et l’élimination de l’atome d’azote, sera analysé en détail. Ainsi, les effets sur l’adsorption des composés

(28)

azotés seront étudiés. Les résultats obtenu à partir de l’HDN des molécule individuels seront comparés afin d’évaluer la différence en effets de l’acidité de support sur l’HDN de composé basique et neutre. Le deuxième objectif de la thèse est d'étudier la voie réactionnelle en HDN d’une charge réelle et de transposer les résultats obtenus à partir des molécules modèles en HDN de la charge. Un mélange de Gazole Straight Run et Gazole Coker est choisi pour cette étude. Le Gazole Coker est un distillat moyen de faible qualité (faible indice de cétane, teneur élevée en soufre, d'azote et aromatiques), donc et il devra être purifié par l’hydrotraitement pour répondre aux spécifications différentes sur la qualité du produit. La conversion d’HDN de la charge réelle sera étudiée par la détermination de la teneur en azote total et azote basique. La Spectrométrie de Masse à la Résonance Cyclotronique Ionique et à Transformé de Fourier sera utilisée pour caractériser les composés azotés. Cela nous permettra d'évaluer le mécanisme réactionnel et de comparer la réactivité en HDN des différentes familles de composés azotés dans la charge. De plus, la discrimination des effets d’acidité du support sur l'HDN de la charge sera étudiée.

La thèse est structurée en 5 chapitres:

(1) Les études bibliographiques sur le mécanisme réactionnel et la cinétique réactionnelle de l’HDN des molécules modèles et des charges réelles. Les effets de l'acidité de supports sont également discutés.

(2) Les caractérisations de catalyseurs: les propriétés texturales, la fonction acide et la fonction d'hydrogénation ainsi la quantification et la dispersion de la phase active.

(3) Les effets de l’acidité du support sur l’HDN de la quinoléine.

(4) Les effets de l'acidité du support sur l’HDN de l’indole, puis la comparaison des aspects cinétiques et d'adsorption entre l’HDN de ces deux molécules modèles.

(5) A partir des molécules modèles à la charge réelle: HDN du mélange de Gazole Straight Run et Gazole Coker.

(29)

General introduction

The growth of worldwide fuel demand, the crude oil depletion as well as the rise of impurities content in crude oil and emission control requirements are the principal factors which require the improvement of the quality of refining processes. In the long term, oil refining industry will have to adapt to changes in the mix of demand for refined products and modifications in crude oil qualities. Hydrotreating and upgrading processes of heavy petroleum cuts in refinery are increasingly needed in order to produce lighter and cleaner fuels. Hydrotreating reactions play two important roles: (i) the removal of sulfur and aromatic compounds in petroleum fractions for satisfying fuels quality and environmental regulations; (ii) the purification of petroleum fractions for further downstream processing by other catalytic reactions. The implementation of a hydrotreating stage before these upgrading processes prevents the poisoning of catalysts and thus improves the process conversion.

The use of hydrodenitrogenation (HDN) catalysts is increasingly important due to the demand for upgrading heavy feedstocks and drastic effects of nitrogen containing organic compounds on downstream oil refining processes and on the specifications of final products. N compounds cause the poisoning of acid catalysts in upgrading processes such as hydrocracking and fluid catalytic cracking, even below 50 ppm of nitrogen. They also act as inhibitors on deep hydrodesulphurization and hydrodearomatization due to the competitive adsorption on catalytic active sites of nitrogen compounds. Attempts to improve the formulation of hydrotreating catalysts could be performed via the modification of support acidity of sulfide catalysts, which showed effects on the activity of hydrotreating catalysts. A rational design of better HDN catalyst requires a better understanding of how catalytic sites influence activity as well as selectivity. Kinetic study of HDN reactions is a key tool for this approach.

It is difficult to carry out comprehensive mechanistic studies on real feedstock due to complex mixtures of many different molecules. Therefore, a first and simpler option is to use well-defined model molecules for which the reaction network can be studied in detail. The first objective of the thesis is to discriminate the role of support acidity of sulfide NiMo catalysts in the HDN of nitrogen containing model molecules. For that, the two catalysts with different support acidity, the one supported on γ-alumina (the reference catalyst) and the second supported on amorphous silica-alumina (prepared by impregnation method) from IFP Energies Nouvelles are chosen. Quinoline and indole, respectively basic and neutral nitrogen compounds, are selected as model compounds. The support acidity effects will be investigated by correlating catalyst's characterization data (of support acidity and active phase) and an advanced kinetic model of quinoline and indole HDN. The role of support acidity on each elemental step of the complex reaction network of quinoline and indole HDN, including the hydrogenation, the ring opening and N-removal steps, will be analyzed in detail. As

(30)

well, the effects of support acidity on the adsorption of nitrogen compounds will be investigated. Results obtained from the HDN of quinoline and indole will be compared each other in order to evaluate the difference in the support acidity effects on the HDN of basic and neutral compound.

The second objective is to investigate the HDN mechanism of a real petroleum feed and to transpose the results obtained from the study of model molecules to the HDN of a real petroleum feed. A mixture of Straight Run and Coker Gas Oils is chosen as feed. A Coker Gas Oil is a low quality middle distillate (low cetane index, high content of sulfur, nitrogen and aromatic) and it requires upgrading by hydrotreating to meet the different specifications on product quality. The HDN conversion of the real feed will be followed, distinguishing total and basic nitrogen content. Fourier Transform Ion Cyclotron Resonance Mass Spectrometry (FT-ICR/MS) will be used to characterize the nitrogen compounds. This will allow us to evaluate the HDN reaction pathway (hydrogenation, ring opening, N-removal reaction steps) and to compare the reactivity towards HDN of different nitrogen families in the feed. As well, we expect to discriminate the support acidity effects on the HDN of the real feed.

The thesis is structured into 5 chapters:

(1) Bibliographic studies on the HDN reaction mechanism and reaction kinetic of model molecules and the real petroleum feed. The various support acidity effects are also discussed.

(2) Catalyst characterizations: the two catalysts are characterized textural properties, metal loading, the acid function, hydrogenation function and the active phase dispersion and content.

(3) Effects of support acidity on the quinoline HDN

(4) Effects of support acidity on the indole HDN, and comparison of kinetic and adsorption aspects between the indole HDN and the quinoline HDN.

(5) From the model molecules to the real petroleum feed: HDN of the mixture of Straight Run and Coker Gas Oil.

(31)

Chapter 1

(32)

Chapter 1: Bibliography studies

1.1. Introduction

The worldwide economic growth during the last centuries continues to drive the demand for energy and transportation fuels, in particularly, for environmentally clean and light fuels due to severity of emission standards. The European market of refined oil products has become increasingly out of balance with changing domestic demands. The increasing popularity of diesel-powered private vehicles results in an increasing shortfall of diesel and a

growing surplus of gasoline 1. The projected changes in fuel demand until 2030 are illustrated

in Figure 1-1 1. In general, the middle distillate demand including jet/kerosene and

gasoil/diesel is forecast to increase from 50% (in 2010) to 59% (in 2030).

Figure 1-1: Total European refined products demand in 2010 and 2030 1

Moreover, the quality of extracted crude oils will be increasingly poorer. The proportion of heavy crude oil is rising and these heavy oil fractions have a high content of aromatics and of sulfur and nitrogen compounds. In order to convert heavy oil fractions, for which there is little market demand, into light and middle distillates, for which demand is growing as shown above, hydrocracking and catalytic cracking are very attractive processes.

The growth of worldwide fuel demand, the crude oil depletion as well as the rise of impurities content in crude oil and emission control requirements are the principal factors which require the improvement of the quality of refining processes. In the long term, the refining industry will have to adapt to further geographical shifts in demand, changes in the mix of demand for refined products and modifications in crude oil qualities. There is a need for more conversion of heavy petroleum cuts, more hydrotreating and upgrading capacity in refinery in order to produce lighter and cleaner fuels. Therefore, studying processes and catalysts which are used for conversions of heavy petroleum fractions will be a challenge for refiners and scientists.

(33)

1.2. Distribution of nitrogen compounds in petroleum fractions

In petroleum fractions, nitrogen compounds found fall into one of two types: non- heterocycles and heterocycles. The non-heterocycles include aniline and aliphatic amines. Aliphatic amines are rapidly decomposed in hydrotreating conditions. The heterocyclic nitrogen compounds are usefully classified into 2 groups: the six-membered pyridinic ring and the five-membered pyrrolic ring. Some heterocyclic compounds in these two groups are given in Figure 1-2. N N N N N H N H N_H N H N H NH N NH N Porphyrine 1,4 - dimethylcarbazole Carbazole Indole Pyrrole 7,8 - benzoquinoline Acridine Quinoline Pyridine 3,4 - benzocarbazole Aniline NH₂ N H tetrahydroquinoline N H tetrahydrocarbazole

Figure 1-2: Several model nitrogen compounds in petroleum fractions 2–7

In six membered nitrogen heterocycles, the free pair of electron on nitrogen atom is not involved in the π-electron system of aromatic ring and it accounts for the basicity of this type of compound. During reactions in the presence of acid catalysts, basic nitrogen containing compounds will preferentially utilize the nitrogen atom for bonding to the catalyst surface via chemisorption, if the nitrogen atom is not sterically hindered by methyl-substituted groups 8.

In five membered nitrogen heterocycles, the electron pair on the nitrogen atom is conjugated with the π-electron cloud of ring. Therefore, the basicity of nitrogen in compounds of this type is almost suppressed. It means that the electron pair on nitrogen atom is not available for interacting with the acid catalyst surface. However, in comparison with benzene rings, the five-membered nitrogen ring is relatively richer in electrons, and thus, this higher density of electrons in these compounds can be expected to create stronger adsorption with the catalyst surface.

(34)

From a point of view of C-N bond energy, the scission of Csp3-N bond is easier than

that of Csp3-Csp3 bond but more difficult than that of Csp3-S bond. In fact, bond dissociation

energies of three types of bonds Csp3-N, Csp3-Csp3, Csp3-S are 305, 345 and 272 kJ/mole,

respectively 9. The breaking of a Csp3-N bond is much easier than that of a Csp2=N bond,

which has a bond energy of 614 kJ/mole 9. Therefore, HDN reactions are generally more

difficult than HDS reactions and the removal of nitrogen from nitrogen heterocycles over conventional hydrotreating catalysts proceeds through a complete hydrogenation of the

aromatic rings, followed by an irreversible C-N bond scission due to the strong C-N bond 8.

Certain properties such as basicity and reactivity toward HDN of nitrogen compounds depend on their structure, particularly their electronic configuration. The relative basicity of

several model compounds was represented by their pKa (acid dissociation constant at

logarithmic scale) or their proton affinity, which is considered to be an indicator of the interaction of molecules with Bronsted sites in gas phase 10 (Table 1-1).

Table 1-1: pKa and proton affinity (PA) values of some nitrogen model compounds 8,10–14

Compound pKa PA (kcal/mol) Dodecylamine 10.6 -Aniline 5.0 213.5 Pyridine 5.2 222 Piperidine 11.1 229.7 Quinoline 4.9 227.6 1,2,3,4-Tetrahydroquinoline 5.0 225 Acridine 5.6 232.7 Ammonia 9.25 207.6 pyrrole 0.4 209.4 Indole -3.6 223.3 2,3-dihydroindole 5.0 - Carbazole -6.0 -

When petroleum fractions are heavier, their metal, sulfur and nitrogen content are higher. In petroleum fractions and crude oils, the nitrogen content is about 5-20 times lower than the sulfur content. In vacuum gas oil and heavy coker gas oil, this is typically higher than 1000 ppm 15.