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Supercritical Pyrolysis of Toluene Khue Dang Nguyen Louisiana State University and Agricultural and Mechanical College

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Supercritical Pyrolysis of Toluene Khue Dang Nguyen Louisiana State University and Agricultural and Mechanical College Louisiana State University LSU Digital Commons LSU Master's Theses Graduate School 2011 Supercritical pyrolysis of toluene Khue Dang Nguyen Louisiana State University and Agricultural and Mechanical College Follow this and additional works at: https://digitalcommons.lsu.edu/gradschool_theses Part of the Chemical Engineering Commons Recommended Citation Nguyen, Khue Dang, "Supercritical pyrolysis of toluene" (2011). LSU Master's Theses. 491. https://digitalcommons.lsu.edu/gradschool_theses/491 This Thesis is brought to you for free and open access by the Graduate School at LSU Digital Commons. It has been accepted for inclusion in LSU Master's Theses by an authorized graduate school editor of LSU Digital Commons. For more information, please contact [email protected]. SUPERCRITICAL PYROLYSIS OF TOLUENE A Thesis Submitted to the Graduate Faculty of the Louisiana State University and Agricultural and Mechanical College in partial fulfillment of the requirements for the degree of Master of Science in The Department of Chemical Engineering by Khue Dang Nguyen B.S., The University of Southern Mississippi, 2008 December 2011 Table of Contents Acknowledgements ........................................................................................................................ iv Abstract ...........................................................................................................................................v Chapter 1. Introduction ....................................................................................................................1 1.1 Background ............................................................................................................................1 1.2 Purpose of the Study .............................................................................................................2 1.3 Structure of the Thesis ...........................................................................................................4 Chapter 2.Literature Review ...........................................................................................................5 2.1 Introduction ...........................................................................................................................5 2.2 Supercritical Pyrolysis of Model Fuels ..................................................................................5 2.3 Toluene Pyrolysis ...................................................................................................................8 2.4 Conclusion ............................................................................................................................18 Chapter 3. Experimental Methods and Analysis ...........................................................................20 3.1 Introduction .........................................................................................................................20 3.2 Supercritical Fuel Pyrolysis Reactor System ......................................................................20 3.3 Product Analysis ..................................................................................................................23 3.3.1 Gas-Phase Product Analysis by Gas Chromatography .................................................23 3.3.2 Liquid-Phase Product Analysis by Gas Chromatography ............................................24 3.3.3 Liquid-Phase Product Analysis by High-Pressure Liquid Chromatography ................24 3.4 Concluding Remarks ............................................................................................................27 Chapter 4. Identification of Products of Supercritical Toluene Pyrolysis ....................................28 4.1 Introduction .........................................................................................................................28 4.2 Identification of Gas-Phase Products by Gas Chromatography ..........................................28 4.3 Identification of Liquid-Phase Products by Gas Chromatography .....................................28 4.4 High-Pressure Liquid Chromatography ...............................................................................33 4.5 Summary .............................................................................................................................62 Chapter 5. Formation of Products of Supercritical Toluene Pyrolysis .........................................63 5.1 Introduction .........................................................................................................................63 5.2 Alkane and Alkene Products ...............................................................................................63 5.2.1 Alkane and Alkene Product Formation Mechanisms ....................................................63 5.2.2 Alkane and Alkene Product Yields ...............................................................................68 5.3 One-Ring Aromatic Hydrocarbon Products .........................................................................69 5.3.1 One-Ring Aromatic Product Formation Mechanisms ...................................................70 5.3.2 Temperature and Pressure Effects on One-Ring Aromatic Product Yields ..................72 5.4 Two-Ring Aromatic Hydrocarbon Products ........................................................................73 5.4.1 Biphenyl ........................................................................................................................73 5.4.2 Diphenylmethane ..........................................................................................................77 5.4.3 Bibenzyl ........................................................................................................................79 5.5 Polycyclic Aromatic Hydrocarbon Products ........................................................................81 5.5.1 Fluorene .........................................................................................................................81 5.5.2 Anthracene and Phenanthrene .......................................................................................84 5.5.3 Phenyl-Substituted Aromatic Products .........................................................................87 5.5.4 Benzofluoranthene .........................................................................................................92 ii 5.5.5 Indeno- and Naphtho-Fused PAH ................................................................................94 5.5.6 Summary of Results and Conclustion Related to PAH .................................................99 5.6 Summary and Conclusions .................................................................................................100 Chapter 6. Conclusions and Recommendations ..........................................................................102 References ...................................................................................................................................105 Appendix A. Reverse-Phase HPLC Chromatograms for the Quantification of Two- to Five-Ring Aromatic Hydrocarbons .......................................................................110 Appendix B. Numerical Values of Product Yields .....................................................................116 B.1 Alkane and Alkene Product Yields ...........................................................................116 B.2 Benzene Product Yields ............................................................................................117 B.3 Biphenyl and Terphenyl Product Yields ...................................................................118 B.4 Diphenylmethane and Bibenzyl Product Yields .......................................................120 B.5 Fluorene and Phenylfluorene Product Yields ............................................................121 B.6 Anthracene and Phenylanthracene Product Yields ...................................................122 B.7 Phenanthrene and Phenylphenanthrene Product Yields ............................................123 B.8 Benzofluoranthene Product Yields............................................................................124 B.4 Indenofluorene and Naphthofluorene Product Yields ...............................................125 Vita ..............................................................................................................................................126 iii Acknowledgements I gratefully acknowledge the Air Force Office of Scientific Research, for providing the necessary funding for this research. The most important person I must thank is my advisor, Dr. Judy Wornat, for her wisdom, patience, and encouragement during this endeavor. I also want to thank the members of my group, Sean Bagley, Franz Ehrenhauser, and Nimesh Poddar for their help with my research and help with the analytical equipments. And finally I am forever grateful to my parents, Vang Nguyen and Thuy Tran, and my siblings, Huyen, Hien, and Amanda, for their love and support. iv Abstract The development of future high-speed aircrafts will required the jet fuel to act as the primary engine coolant to absorb excess heat produced by the engine components. To aid in removing the excess heat and reducing the aircraft’s weight, future jet fuels used for high-speed aircrafts will act as both coolant and fuel; however, by exposing the fuels to temperatures and pressures above their critical point, they undergo pyrolysis to form
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