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STUDY of CARBON AEROGEL SUPPORTED Fe CATALYSTS for BIOMASS GASIFICATION GAS CLEANING

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STUDY of CARBON AEROGEL SUPPORTED Fe CATALYSTS for BIOMASS GASIFICATION GAS CLEANING UNIVERSIDAD DE CONCEPCIÓN DEPARTAMENTO DE INGENIERÍA QUÍMICA STUDY OF CARBON AEROGEL SUPPORTED Fe CATALYSTS FOR BIOMASS GASIFICATION GAS CLEANING POR OSCAR GÓMEZ CÁPIRO Tesis presentada a la Facultad de Ingeniería de la Universidad de Concepción para optar el grado de Doctor en Ciencias de la Ingeniería con mención en Ingeniería Química Tutor: Prof. Romel Mario Jiménez Concepción, PhD. Departamento de Ingeniería Química Universidad de Concepción Co-tutor: Prof. Luis Ernesto Arteaga Pérez, PhD. Departamento de Ingeniería en Madera Universidad del Bío-Bío Concepción, Chile. Junio de 2020 Se autoriza la reporducción total o parcial , con fines académicos , por cualquier medio o procedimiento, incluyendo la cita bibliográfica del documento. Advisor: Prof. Romel Mario Jiménez Concepción, PhD. Chemical Engineering Department University of Concepción Co-advisor: Prof. Luis Ernesto Arteaga Pérez, PhD. Department of Wood Engineering University of Bío-Bío Examination Prof. Ximena García Carmona, PhD. Committee Chemical Engineering Department University of Concepción Prof. Fernando Mariño, PhD. ITHES University of Buenos Aires; CONICET i Dedicatoria Dedicatoria A mi abuela Dora, Doña Cedora del Rosario Muñoz y Anoceto… ii Agradeciemientos Agradecimientos Quisiera aprovechar para agradecer a algunas de las personas que han hecho posible que se realizara el trabajo que se detalla más adelante. Comenzaré por dar gracias al profesor Luis Ernesto Arteaga Pérez que no solo me guío académicamente, sino que me ofreció apoyo en todo, abriendo su casa y su familia para recibirme en Chile, por eso debo agradecer también a su esposa Yannay Casas Ledón. Quiero dar gracias al profesor Romel Mario Jiménez Concepción quien guió mi trabajo académico y mi formación como doctor. Ambos no solo fueron tutores, sino soportes en el cambio que implicó dejar mi país. Mi gratitud también es para mis amigos en Cuba, quienes con un simple mensaje alegraban los días a pesar de la distancia, especialmente a Osvaldo de la Fuente, Dailenys Garcia y Freddy Santo, Andrés Feitó y muy especialmente a Yenisleidys Rodríguez, Eduardo González y Osdeny Chaviano. Chile también me dio nuevos amigos a los que quiero agradecer su presencia y paciencia para soportarme, esto incluye a Karen Aravena, Álvaro Iglesia, Isidora Ortega, Paulina Melo, José Luis Daroch, Diego Villagrán y Carla Riffo. Además, a todos los compañeros de doctorado con los que he compartido desde el 2015, en especial a los que me recibieron en mis inicios, Nabin Kumar, Norberto Abreu, Raydel Manrique, Yaine Beltrán y su familia, y a mi buen amigo Luis Pino. Corresponde hacer un agradecimiento especial para Bryan Gómez y su esposa María Amalia Salazar que pasaron a ser como mi familia aquí y a todos los que conocí gracias a ellos. Son unos amigos excepcionales que nos hacían sentir en casa tanto a mí como a mi esposa. A lo largo del desarrollo del doctorado fueron llegando otros que poco a poco se hicieron imprescindibles, pude y puedo contar con ellos para todo y siempre estaré agradecido de la feliz coincidencia de encontrar a Jessica Borges, Daviel Gómez, Maray Ortega y Anamary Pompa en este camino. Dentro del marco del trabajo, muchos contribuyeron en los experimentos y la caracterización de materiales. No sería posible presentar los resultados finales de esta investigación sin la colaboración de Aaron Delgado, Adrian Hinckle, Nicolás Grob y Kimberley Matschuk. También apoyaron el trabajo Mónica Uribe en el GEA y los encargados del Centro de Microscopía Electrónica. Requieren un reconocimiento especial todas las personas con las que coincidí en el Laboratorio de Carbono y Catálisis (CarboCat) y en la Unidad de Desarrollo Tecnológico, en especial Mauricio Flores, Héctor Grandón, Robert Irribarra, Manuel Morales, iii Agradeciemientos Patricia Olivera y Cristina Segura; además de mis coterráneos Daniel Travieso y Gustavo Cabrera. Igualmente doy gracias a los profesores que me impartieron clases en diferentes departamentos de la Universidad de Concepción y en especial del Departamento de Ingeniería Química que a través de clases o consejos y comentarios sobre este trabajo en diferentes instancias hicieron posible mejorar todos los aspectos de la investigación. Mi agradecimiento incluye, por supuesto, al personal administrativo de dicho departamento, especialmente a Erika Carrasco, Carol Soto y Héctor Fierro. Agradezco la formación recibida que permitió el honor de ser aceptado en el programa de doctorado. Todos mis maestros y profesores a todos los niveles aportaron algo sobre lo que me apoyé para llegar hasta aquí, especialmente a Aleida Rodríguez, mi profesora de secundaria que me inició en los caminos del estudio las ciencias. Son las familias las que sustentan todo el trabajo que pueda hacerse como estudiante y en este caso venir hasta Chile requirió el sacrificio de la familia de mi esposa que tuvo que verla partir, por eso les estoy eternamente agradecido a sus padres Teresita González y José Antonio González, a su hermano Adriamny González y a toda su familia. Agradezco a mi familia, a mi tía Mercedes Gómez, a mi abuela Cedora Muñoz, a quien va dedicada esta tesis, y sobre todo a mi madre Claribel Cápiro y mi padre Oscar Gómez que forjaron este camino para mí, aunque me haya llevado lejos de ellos. Todo lo que implicó dejar mi país, mis amigos y mi familia también lo sufrió mi esposa Amaidy González. Sin mi compañera de viaje, sin su apoyo incondicional, su amor y cuidado, no existiría tesis ni me hubiese graduado. Fue todo, desde correctora de trabajos, consejera, sustento, hasta enfermera en los momentos más difíciles. A ella le debo esto y nunca le podré agradecer lo suficiente. iv Content List of Contents i. Introduction. ............................................................................... xiv ii. Technical Problem: ........................................................................ 5 iii. Hypothesis: ..................................................................................... 5 iv. General objective: .......................................................................... 5 v. Specific objectives: ......................................................................... 5 1 Chapter 1: Background. ................................................................ 6 1.1. Chile's energy situation. .............................................................. 6 1.2. Lignocellulosic biomass for energy production. Thermochemical conversion of biomass. Applications. ...................... 6 1.2.1. Liquefaction. .......................................................................... 8 1.2.2. Torrefaction. .......................................................................... 8 1.2.3. Pyrolysis. ................................................................................ 9 1.2.4. Combustion. .......................................................................... 9 1.2.5. Gasification. ......................................................................... 10 1.3. Distributed generation. ............................................................. 14 1.4. Problems related to biomass gasification gases. ...................... 15 1.5. Gas cleaning. .............................................................................. 17 1.5.1. Physical and mechanical removal. ..................................... 18 1.5.2. Thermal cracking. ............................................................... 18 1.5.3. Catalytic cracking and reforming. ..................................... 19 1.5.4. Iron as active phase in catalytic tars removal. ................... 22 1.6. Chars as support. ...................................................................... 24 1.6.1. Carbon aerogels. ................................................................. 25 1.6.2. Carbon aerogels as support. ............................................... 26 1.7. Kinetic aspects. .......................................................................... 27 1.7.1. Toluene decomposition. ...................................................... 27 1.7.2. Ammonia decomposition. ................................................... 32 1.8. Research questions. ................................................................... 33 v Content 2 Chapter 2: Carbon Aerogel-Supported Iron for Gasification Gas Cleaning: Ammonia Adsorption. ....................................................... 35 2.1. Introduction. .............................................................................. 36 2.2. Materials and Methods. ............................................................ 42 2.2.1. Microfibers Treatment. ...................................................... 42 2.2.2. Carbon Aerogel Preparation. Carbonization. ................... 43 2.2.3. Catalysts Preparation. ........................................................ 43 2.2.4. Compositional Analysis. ...................................................... 44 2.2.5. N2 Adsorption-Desorption at 77K. ..................................... 44 2.2.6. Thermal Resistance. ............................................................ 44 2.2.7. X-Ray Diffraction (XRD). ................................................... 45 2.2.8. Raman Spectroscopy Analysis. ........................................... 46 2.2.9. Transmission Electron Microscopy (TEM). ...................... 47 2.2.10. Ammonia Adsorption Experiment. .................................... 47 2.3. Results and Discussion. ............................................................. 50 2.3.1. Characterization
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