Université Pierre et Marie Curie Ecole doctorale 391 Institut J ean Le Rond d’ Al emb ert / Fluid es R éact ifs et Turbulence On the Performance of Oxidation Catalysts and SC R Catalysts in the Presence of Alkali Compounds Representative of Biofuel Contaminants: from the Commercial Catalysts to the Active Phase Par M. Yiquan XIE Thèse de doctorat de Génie Chimique Dirigée par M. Patrick DA COSTA et Mme. Maria Elena G ALVEZ -PARRUCA Présentée et soutenue publiquement le 25/10/2017 Devant un jury composé de : M. DUJARDIN Christophe, Professeur de s Universités, École Nationale Supér ieure de Chimie de Lille (Rapporteur) M. GARIN Francois, Professeur, Université de S trasbourg (Rapporteur) M. C AVADIAS S iméon, P rofesseur, U niversité Pierr e et M arie Curie (Examinateur) M. DA COSTA Patrick, Professeur, Institut Jean le Rond d’Alembert, Université Pierre et Marie Curie (Directeur d e Thèse) Mme. GA LVEZ -PARRUCA M aria Elena, M aître de Conférences ( Habilitation), I nstitut Jean le Rond d’Alembert, U niversité Pierr e et M arie Curie (Co -D irecteur d e Thèse) M. T ATOULIAN M ichael, P rofesseur, C himie ParisTech, C NRS Institut de Recherche de Chimie P aris ( Examinateur) Université Pierre et Marie Curie Ecole doctorale 391 Institut J ean Le Rond d’ Al emb ert / Fluid es R éact ifs et Turbulence On the Performance of Oxidation Catalysts and SCR Cat alysts in the Presence of Alkali Compounds Representative of Biofuel Contaminants: from the Commercial Catalysts to the Active Phase Par M. Yiquan XIE Thèse de doctorat de Génie Chimique Dirigée par M. Patrick DA COSTA et Mme. Maria Elena GALVEZ -PARRUCA Présentée et soutenue publiquement le 25/10/2017 Devant un jury composé de : M. DUJARDIN Christophe, Professeur de s Universités, École Nationale Supér ieure de Chimie de Lille (Rapporteur) M. GARIN Francois, Professeur, Université de S trasbourg (Rapporteur) M. C AVADIAS S im éon, P rofesseur, U niversité Pierr e et M arie Curie (Examinateur) M. DA COSTA Patrick, Professeur, Institut Jean le Rond d’Alembert, Université Pierre et Marie Curie (Directeur d e Thèse) Mme. GA LVEZ -PARRUCA M aria Elena, M aître de Conférences ( Habilitation), Ins titut Jean le Rond d’Alembert, U niversité Pierr e et M arie Curie (Co -D irecteur d e Thèse) M. T ATOULIAN M ichael, P rofesseur, C himie ParisTech, C NRS Institut de Recherche de Chimie P aris ( Examinateur) Acknowledgments Acknowledgments This doctoral thesis, though published by one author, could not have been possible without the aid of dozens of other people in a way or other over the course of my three-year study at UPMC. It has been an unforgettable, rewarding, interesting, and sometimes even challenging experience pursuing this Ph.D., and it is difficult to show my gratitude to everyone appropriately for their contributions to my persistence and success along this very journey. First of all, I would like to express my genuine appreciation to Professor Patrick DA COSTA, Dr. Hab. Marie Elena GALVEZ and Dr. Alexis MATYNIA for being my thesis supervisors. Without their scientific guidance, advice and patience, this dissertation can by no means come to public notice. A special thank is due to Prof. Patrick DA COSTA for encouraging me to do a PhD thesis, and for accepting me to his laboratory. As a member of the Fluides Réactifs et Turbulence (FRT) group of Prof. DA COSTA, I appreciate deeply his spiritually support, his pronounced organization of the research topic, his permanent readiness for discussion, his great interest in the success of this work and his high motivation for all his group members. I was also quite fortunate that my PhD thesis can be examined by two reviewers, Prof. Christophe DUJARDIN (Ecole Nationale Superieure de Chimie de Lille) and Prof. François GARIN (Université de Strasbourg). Special thanks belong to them for making my thesis better. Furthermore, I would like to express my gratitude to other members of my Jury, Prof. Siméon CAVADIAS (UPMC) and Prof. Michael TATOULIAN (Chimie ParisTech). I thank all the members of my Jury for bringing this thesis to a close. I thank Dr. Acácio Mendes, for getting me familiar with the experimental facilities and for his team building effort, in particular, during the first year of my thesis. I also wish to acknowledge other members of the FRT group, Hongrui LIU, Sandrine DUONG, Armando IZQUIERDO, Radosław DĘBEK, Johnny ABBOUD and Laureanne PARIZOT. I thank all of you for all the aid you provided, all the moments we shared and all the conversion we had. I Acknowledgments Meanwhile, I want to convey my gratitude to all other professors, researchers, administrators, engineers and technicians from the laboratory where I carried out my research activities and to whom I can turn for help, namely, Prof. Stéphane ZALESKI, Prof. Philippe GUIBERT, Prof. Guillaume LEGROS, Maya DAOU, Evelyne MIGNON, Anne MARCHAL, Renaud JALAIN, Jean-Marie CITERNE, Jérôme BONNETY, Hugo DUTILLEUL, Christian OLLIVON, Dominique BUSQUET, Jêrome PÉQUIN, and Frédéric SEGRETAIN. I was quite privileged to work with 2 master students over the past 3 years: Elza RODRIGUES and Achraf HAMSI. Elza worked with me on the aging study of monolith diesel oxidation catalysts, and this led to the publication of my first article during this thesis. Achraf came to the FRT group when I was at the final year of my thesis, and he aided me in the poisoning study of monolith selective catalytic reduction catalysts. Their help in conducting some of the catalytic tests and catalysts characterizations as part of my thesis was indispensable to its completion. I am sincerely grateful to both of them. Prior to my arrival at UPMC, I was inspired by many devoted teachers, friends and classmates. Particularly, I would like to use this opportunity to show my gratitude to Prof. Haochun ZHANG for acting as my guarantor without hesitation when I asked. Undoubtedly, I am indebted to all the teachers, friends and classmates who witnessed my personal growth and even contributed to it. ZNN has, for over two years, chosen to enhance the cohesion of our coterie, sharing with me her life and her knowledge, for which I am exceptionally grateful. She has been a supportive person throughout my late 20s, ensuring that the stress was never overwhelming and walking with me through up and down. In addition, she has patiently dealt with my awful interaction in communication, even occasionally having to bear it. I look forward to journeying with you as a member of a "big" group. I would be incredibly remiss if I did not acknowledge the immense love and support from my family. I feel blessed to have you as a strong backing for my pursuing greater success and impenitent life. I dedicate this thesis to you. II Acknowledgments Institutional acknowledgements belong to the two providers for catalysts, Continental AG for the commercial diesel oxidation catalysts, Umicore for the commercial selective catalytic reduction catalysts, and to China Scholarship Council (CSC) for the financial support of my three-year PhD thesis program. III Abstract Abstract Due to global lean exhaust gas and new emission regulations, exhaust after-treatment systems of diesel engines are getting more and more sophisticated and comprise a series of catalytic units. In the present work, two of these catalytic systems were studied, Diesel Oxidation Catalysts (DOC) and Selective Catalytic Reduction (SCR) catalysts. Particular attention is paid to their performance in the presence of alkali compounds when bio-diesel is utilized as the alternative fuel. Firstly, this thesis focuses on the catalytic behavior of the Diesel Oxidation Catalyst using different aging characteristics of road mileage in order to improve the efficiency of an ammonia SCR system on an after-treatment line composed by a DOC + DPF + SCR. The studied catalyst is a commercial diesel oxidation catalyst (Pt/Pd/Al2O3) provided by Continental. Hydrothermal aging under different conditions on carrots of monolith were performed. The results of aging study on DOC reveal that thermal aging significantly affects the overall oxidation activities of the catalysts. It turns out that mild thermal aging actually activates the catalyst. Mild thermal aging on the catalyst improves the oxidation performance of C3H6 as well as CO to a large extent while severe aging contributes a little bit. NO oxidation over severely aged catalyst, however, gets better. Also studied in the monolith form over the commercial DOC, the influence of the addition of different alkali metal species (K and Na) on the commercial DOC through catalytic tests performed on this structured catalyst under multicomponent (C3H6 / CO / NO / NO2) co-feeding conditions was explored. The results of doping of alkali metals on a commercial DOC illustrate that the introduction of dopants leads to either negative or positive impacts on the catalytic oxidation. The K addition leads to a promotion of oxidation reactions while the Na addition inhibits the same reactions. There is no impact of exhaust gas composition on the ranking of catalysts. However, it was shown that the presence of NO2 promotes the oxidation reaction whereas in the presence of NO, the competition in terms of oxidation in the same catalytic sites leads to a shift of light off temperature for CO and C3H6 to higher temperatures. IV Abstract Aiming at investigating the effects of the presence of different alkali metal species on the DOC at the level of active phase, homemade bimetallic DOC is prepared and then different alkali metal species incorporated. The catalytic activities test results of doping of alkali metals on a model DOC demonstrate that the addition of alkali compound (K or/and Na) leads to a promotion of the C3H6 oxidation reactions while incurs an inhibition on the NO conversion.