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In-Situ Characterization of the Reaction Progress of the Fluid Catalytic Cracking Reactions by Laser Diagnostic Techniques

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In-Situ Characterization of the Reaction Progress of the Fluid Catalytic Cracking Reactions by Laser Diagnostic Techniques In-situ characterization of the reaction progress of the fluid catalytic cracking reactions by laser diagnostic techniques Sandra Milena López Zamora Universidad Nacional de Colombia Facultad de Minas, Departamento de Procesos y Energía Medellín, Colombia 2018 In-situ characterization of the reaction progress of the fluid catalytic cracking reactions by laser diagnostic techniques Sandra Milena López Zamora Thesis submitted as partial requirement to obtain the title of degree of Doctor of Philosophy in Engineering Director: Ph.D., Alejandro Molina Codirector: Ph.D., Hugo de Lasa Research group: Grupo de Investigación en Bioprocesos y Flujos reactivos Universidad Nacional de Colombia Facultad de Minas, Departamento de Procesos y Energía Medellín, Colombia 2018 A mis padres: José Fernando e Irene A mi hermana Mariluz Gracias por estar ahí cuando más los necesito, porque es posible alcanzar cada sueño al contar con ustedes To my eternal friend Mike Mosley Thanks for being always there La educación es el gran motor del desarrollo personal. Es a través de la educación como las hijas de un campesino pueden convertirse en una médica y una ingeniera, el hijo de un minero puede convertirse en el jefe de la mina, o el hijo de trabajadores agrícolas puede llegar a ser presidente de una gran nación Nelson Mandela Acknowledgements I want to express my gratitude to my supervisor Alejandro Molina for his guidance and supervision. I also express my gratitude to my co-supervisor Prof. Hugo de Lasa who gave me all his help, support and for encourage me during the development of this thesis. I truly appreciate the opportunity that professors Hugo de Lasa and Amir Farooq gave me to work and learn with their research teams in the University of Western Ontario (London, Canada) and King Abdullah University of Science and Technology (Thuwal, Saudi Arabia). The financial support from the Colombian Science Foundation (COLCIENCIAS), the Colombian state oil company (ECOPETROL S.A.) under contract No. 0423 2013 and the Emerging Leaders in the Americas Program (ELAP) Canadian Exchange Program is gratefully acknowledged. I would also like to thank Florencia de Lasa for her assistance with the editing of the published paper. To my friends and colleagues: Carlos Rivera, Yulanderson Salguedo, Abdualkaber Alkhlel, Noel Andrés Gómez Mendoza, Juan Esteban Duque, Juan Felipe Hincapié, Daniel Díaz, Juan David Alzate, Jorge Galvis, Danielle Ochoa, Juan José Arias for all the discussion related or not with this research. To Graciela de Lasa for her wisdom and advices. To Berniece Dellow and Susan Mosley for being my friends and support during the hard times. To Dylan Sweetnam, for his support during the last part of this thesis. Finally, I would like to say thanks to López and Zamora families, who are the most important part of my life, and to whom I still say: “... La fijación de metas distingue a unos hombres de otros. Y aquí lo más importante no es alcanzar dichas metas, sino luchar por ellas." (Hector Abad Gómez). Resumen Técnicas analíticas sofisticadas, como espectrometría de masas y cromatografía líquida de alta eficacia (HPLC), pueden ser usadas para medir el contenido de aromáticos y saturados en el alimento y productos del craqueo catalítico fluidizado (FCC). Sin embargo, los métodos ópticos tienen la ventaja de ser rápidos y no intrusivos, operando en modo sin contacto. Las mediciones de absorción láser de la concentración de combustibles se hacen frecuentemente en longitudes de onda del infrarrojo medio (MIR) cerca de 3.4 µm, que se superpone con las fuertes transiciones vibratorias del enlace C-H presente en hidrocarburos y garantiza una detección sensible incluso para longitudes cortas de medición. El espectro MIR para hidrocarburos individuales puede encontrarse en diferentes bases de datos, sin embargo, la información se limita a especies con bajo número de carbonos. En este sentido, se propuso un método de contribución de grupos (GCM) para la predicción del espectro de los diferentes compuestos presentes en una reacción de craqueo catalítico en la región 3200-2800 cm-1. Esta tesis de doctorado considera el desarrollo de una metodología láser para el monitoreo in-situ-libre de partículas del progreso de la reacción de craqueo catalítico fluidizado (FCC) usando componentes modelo. El objetivo es contribuir a la caracterización de la química y especies químicas involucradas en FCC mediante la evaluación discreta del espectro infrarrojo (IR). La metodología propuesta considera el análisis MIR in-situ del cambio en la concentración de los grupos funcionales presentes en el compuesto modelo 1,3,5- triisopropylbenceno (1,3,5-TIPB) como indicador del progreso de la reacción FCC. Esto se realiza en el ánulo del equipo conocido como “CREC Riser Simulator”. De igual manera, el planteamiento considerado postula la aplicación de esta metodología MIR in-situ para la caracterización de los “lumps” de gases livianos y gasolina en el contexto de una unidad FCC industrial usando una botella de muestreo con dos cámaras bajo vacío. Esta investigación fue llevada a cabo en el Grupo de Investigación Bioprocesos y Flujos Reactivos en la Universidad Nacional de Colombia. Se realizó además una pasantía en el grupo de investigación del profesor Hugo de Lasa (Universidad de Western - Ontario, Canadá) la cual permitió el desarrollo de un método de contribución de grupos (GCM) para la caracterización del progreso de la reacción en una reacción FCC modelo. Palabras clave: Craqueo Catalítico Fluidizado (FCC), Método de contribución de grupos (GCM), Mid-IR (MIR), Enlace C-H, Progreso de Reacción. Abstract Sophisticated analytical techniques, such as mass spectrometry and high-performance liquid chromatography (HPLC), can be used to measure aromatic and saturate contents of the Fluid Catalytic Cracking (FCC) feedstock and products. However, optical methods have the advantage of being rapid and non-intrusive, operating in contact-less mode. Laser- absorption measurements of fuel concentration are often made at mid-infrared (MIR) wavelengths near 3.4 µm, which overlap with the strong C-H stretch vibrational transitions of hydrocarbons and guarantee sensitive detection even for short measurement path lengths. The MIR spectra for individual hydrocarbons can be found in different databases, however the information is limited to being used with species having low carbon number. In this sense, a Group Contribution Method (GCM) is proposed for the spectra prediction of the different compounds present in the catalytic cracking reaction in the region 3200-2800 cm-1. This PhD thesis considers the development of a laser diagnostic methodology for “in-situ- free of particles” monitoring of fluid catalytic cracking (FCC) reaction progress using model compounds. The aim is to contribute to the characterization of the chemistry and chemical species involved in FCC through the discrete evaluation of the infrared (IR) spectra. The methodology proposed considers the in-situ MIR analysis of the change in the concentration of functional groups present in the model compound 1,3,5-triisopropylbenzene (1,3,5-TIPB) as indicator of FCC reaction progress. This is performed in the annulus of a CREC Riser Simulator. As well, the considered approach postulates the application of this in-situ MIR methodology for the characterization of the light gases and gasoline lumps in the context of Industrial FCC unit using a sampling bottle with two cameras under vacuum. This research was carried out at the Grupo de Investigación Bioprocesos y Flujos Reactivos at Universidad Nacional de Colombia. An internship in the group of Professor Hugo de Lasa (Western University - Ontario Canada) allowed the development of a Group Contribution Method (GCM) for the characterization of the reaction progress of a model FCC reaction. Keywords: Fluid Catalytic Cracking (FCC), Group Contribution Method (GCM), Mid-IR (MIR), C-H Bond, Reaction Progress. Table of Contents Pág. Acknowledgements .............................................................................................................. VII Resumen ................................................................................................................................ IX Abstract ................................................................................................................................. XI Table of Contents ................................................................................................................. XIII List of Figures ...................................................................................................................... XVI List of Tables ........................................................................................................................ XIX List of symbols and abbreviations ........................................................................................ XXI Introduction ............................................................................................................................1 1. Literature Review ............................................................................................................3 1.1. Fluid Catalytic Cracking (FCC) process ........................................................................ 3 1.1.1. Reaction Chemistry.................................................................................................. 4 1.1.2. Feed characterization .............................................................................................
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