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Tesis Doctoral: Synthesis of Supported ESCUELA DE INGENIERÍAS INDUSTRIALES DEPARTAMENTO DE INGENIERÍA QUÍMICA Y TECNOLOGÍA DEL MEDIO AMBIENTE TESIS DOCTORAL: SYNTHESIS OF SUPPORTED CATALYSTS OF Co, Ni AND Ru USING SUPERCRITICAL CO2 FOR BIOMASS VALORIZATION REACTIONS Presentada por Álvaro Sastre Cuadrillero para optar al grado de doctor por la Universidad de Valladolid Dirigida por: Dra. Ing. Gloria Esther Alonso Sánchez Prof. María José Cocero Alonso ESCUELA DE INGENIERÍAS DEPARTAMENTO DE INGENIERÍA QUÍMICA Y TECNOLOGÍA DEL MEDIO AMBIENTE TESIS DOCTORAL: SYNTHESIS OF SUPPORTED CATALYSTS OF Co, Ni AND Ru USING SUPERCRITICAL CO2 FOR BIOMASS VALORIZATION REACTIONS Presentada por Álvaro Sastre Cuadrillero para optar al grado de doctor por la Universidad de Valladolid Dirigida por: Dra. Ing. Gloria Esther Alonso Sánchez Prof. María José Cocero Alonso Memoria para optar al grado de Doctor, Con Mención Doctor Internacional, Presentada por el Ingeniero Químico: Álvaro Sastre Cuadrillero Valladolid, Junio de 2015 UNIVERSIDAD DE VALLADOLID ESCUELA DE INGENIERÍAS INDUSTRIALES Secretaría La presente tesis doctoral queda registrada en el folio número __________ del correspondiente libro de registro número _______________________ Valladolid, a _______ de __________________ de 2015 Fdo. El encargado del registro Gloria Esther Alonso Sánchez Profesora Titular Departamento de Ingeniería Química y Tecnología del Medio Ambiente Universidad de Valladolid y María José Cocero Alonso Catedrática Departamento de Ingeniería Química y Tecnología del Medio Ambiente Universidad de Valladolid Certifican que: ÁLVARO SASTRE CUADRILLERO ha realizado bajo su dirección el trabajo “Syntheis of Supported Catalysts of Co, Ni and Ru using Supercritical CO2 for Biomass Valorization Reactions”, en el Departamento de Ingeniería Química y Tecnología del Medio Ambiente de la Escuela de Ingenierías Industriales de la Universidad de Valladolid. Considerando que dicho trabajo reúne los requisitos para ser presentado como Tesis Doctoral expresan su conformidad con dicha presentación. Valladolid, a _______ de __________________ de 2015 Fdo. Gloria Esther Alonso Sánchez Fdo. María José Cocero Alonso Reunido el tribunal que ha juzgado la Tesis Doctoral titulada “Syntheis of Supported Catalysts of (Co, Ni and Ru using Supercritical CO2 for Biomass Valorization Reactions” presentada por el Ingeniero Químico Álvaro Sastre Cuadrillero y en cumplimiento con lo establecido por el Real Decreto 99/2011 de 28 de enero de 2011 acuerda conceder por __________________ la calificación de _______________________________. Valladolid, a _______ de __________________ de 2015 PRESIDENTE SECRETARIO 1er Vocal 2o Vocal 3er Vocal “There is no point in doing something in a supercritical fluid just because it’s neat. Using the fluids must have some real advantage” ------------------------------------------------------------------------------------------------------------------ Val Krukonis First International Symposium on Supercritical Fluids, 1988 INDEX ABSTRACT ............................................................................................................ 19 AIMS ....................................................................................................................... 23 CHAPTER I. INTRODUCTION ............................................................................ 25 I.1. Introduction .................................................................................................. 26 I.2. Supercritical Fluids (SCFs) .......................................................................... 27 I.3. Synthesis of Materials in Supercritical Fluids .............................................. 31 I.4. Supercritical Fluid Deposition (SCFD) ........................................................ 33 I.5. Metals in Catalysis and their applications .................................................... 36 I.6. The importance of Support ........................................................................... 37 I.7. References .................................................................................................... 38 CHAPTER II. COBALT-BASED CATALYSTS ................................................... 44 II.1. Introduction ................................................................................................. 45 II.1.1. Cobalt-based Catalysts and their applications ...................................... 45 II.1.2. Deposition of Cobalt using sc-CO2 ................................................................................. 47 II.2. Materials ...................................................................................................... 48 II.2.1. Organometallic Precursor: CoCp2 ....................................................... 48 II.2.2. Support: MCM-41 ................................................................................ 48 II.3. Adsorption isotherms of CoCp2 .................................................................................................... 50 II.3.1. Experimental Set-up for determination of Adsorption Isotherms ........ 50 II.3.2. Results and discussions: Adsorption of CoCp2 on MCM-41 .............. 53 II.3.3. Adsorption Isotherms Modeling .......................................................... 54 II.3.4. Fittings and discussion ......................................................................... 55 II.4. Supercritical Fluid Reactive Deposition of CoCp2 on MCM-41 ................ 58 II.4.1. Catalysts Synthesis Batch Device ........................................................ 58 II.4.2. Optimization: concentration, temperature and pressure ....................... 60 II.4.3. Kinetics of the process ......................................................................... 62 II.4.3.1. Kinetics Model .............................................................................. 64 II.4.4. Sequential loadings .............................................................................. 66 II.4.5. Mass transfer limitations ...................................................................... 66 II.4.6. Conclusions .......................................................................................... 69 II.5. Characterization of Co/MCM-41 catalysts ................................................. 70 II.6. Activity Test: Gasification of Cellulose for Hydrogen production ............. 76 II.6.1. Experimental Device ............................................................................ 77 II.6.2. Thermogravimetric studies on Cellulose pyrolysis .............................. 78 II.6.3. Gas products analysis ........................................................................... 79 II.6.4. Kinetics Model ..................................................................................... 83 II.6.5. Results and discussions ........................................................................ 85 II.7. Conclusions ................................................................................................. 89 II.8. References ................................................................................................... 91 CHAPTER III. NICKEL-BASED CATALYSTS ................................................... 98 III.1. Introduction ................................................................................................ 99 III.1.1. Nickel-based Catalysts and their applications .................................... 99 III.1.2. Deposition of Nickel using sc-CO2 ............................................................................... 101 III.2. Materials .................................................................................................... 102 III.2.1. Organometallic Precursor: NiCp2 ................................................................................... 102 III.2.2. Support: MCM-48............................................................................... 102 III.3. Adsorption isotherms of NiCp2 ................................................................................................... 104 III.3.1. Results and discussions: Adsorption of NiCp2 on MCM-48 .............. 104 III.3.3. Adsorption Isotherms Modeling ......................................................... 105 III.3.4. Fittings and discussion ........................................................................ 107 III.3.5. Adsorption Kinetics ............................................................................ 112 III.3.5.1. Adsorption Kinetics of NiCp2 on MCM-48 ................................ 114 III.3.6. Adsorption Mechanism ....................................................................... 115 III.3.6.1. Adsorption Mechanism of NiCp2on MCM-48 ............................ 117 III.4. Supercritical Fluid Reactive Deposition of NiCp2 on MCM-48 ............... 120 III.4.1. Procedure of Synthesis........................................................................ 120 III.4.2. Results and discussion ........................................................................ 121 III.5. Characterization of Ni/MCM-48 catalysts ................................................. 123 III.6. Activity Test: Hydrogenation of Glucose for D-Sorbitol production ........ 128 III.6.1. Experimental Device ........................................................................... 128 III.6.2. Results and discussions ....................................................................... 130 III.7. Conclusions ...............................................................................................
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