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Evaluation and Products Characterization of Mango Seed Shell and Kernel Conventional Pyrolysis

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Evaluation and Products Characterization of Mango Seed Shell and Kernel Conventional Pyrolysis EVALUATION AND PRODUCTS CHARACTERIZATION OF MANGO SEED SHELL AND KERNEL CONVENTIONAL PYROLYSIS Thesis By JUAN CAMILO MAHECHA RIVAS Presented in the Engineering Faculty of Universidad de los Andes In fulfillment of the requirements for the Degree of CHEMICAL ENGINEER Approved by: Advisor, Rocio Sierra Ramírez, Ph.D. Chemical Engineering Department Bogotá, Colombia January 2020 Evaluation and products characterization of mango seed shell and kernel conventional pyrolysis Juan C. Mahecha-Rivas Department of Chemical Engineering, University of Los Andes, Bogotá, Colombia GENERAL OBJECTIVE To characterize mango seed’s conventional pyrolysis products at optimal conditions for further valorization SPECIFICS OBJECTIVES - To evaluate the influence of temperature of conventional pyrolysis in bio-oil, biochar and biogas yields - To compare the pyrolysis’s yields from kernel, shell and kernel/shell mixture fed. - To characterize biochar, bio-oil, and biogas from mango seed’s kernel and shell pyrolysis - To determine the feasibility of mango seed bio-oil as a biodiesel precursor or additive i TABLE OF CONTENTS Abstract ................................................................................................................................... 1 1. Introduction .................................................................................................................... 1 2. Methods .......................................................................................................................... 4 2.1. Materials and sample preparation ............................................................................ 4 2.2. Biomass characterization ......................................................................................... 4 2.2.1. Ultimate analysis .............................................................................................. 4 2.2.2. Fourier transform infrared spectroscopy analysis (FTIR) ................................ 5 2.2.3. Simultaneous thermogravimetric and differential scanning calorimetry analysis (TGA-DSC) .................................................................................................................... 5 2.3. Pyrolysis Process ..................................................................................................... 5 2.3.1. Tubular furnace................................................................................................. 5 2.3.2. Laboratory-scale pyrolysis ............................................................................... 6 2.4. Bio-oil characterization ............................................................................................ 8 2.4.1. Gas chromatography couple with mass spectrometry analysis (GC-MS) ........ 8 2.4.2. Fourier transform infrared spectroscopy analysis (FTIR) ................................ 8 2.4.3. Calorific value determination ........................................................................... 8 2.4.4. Distillation curve .............................................................................................. 8 2.5. Biochar characterization .......................................................................................... 9 3. Results and discussion .................................................................................................... 9 3.1. Biomass characterization ......................................................................................... 9 3.1.1. Biomass ultimate and compositional analysis .................................................. 9 3.1.2. Biomass FTIR ................................................................................................. 10 3.1.3. Biomass TGA-DSC analysis .......................................................................... 11 3.2. Pyrolysis Process ................................................................................................... 12 3.2.1. Tubular Furnace .............................................................................................. 12 3.2.2. Laboratory-scale pyrolysis ............................................................................. 16 3.3. Bio-oil characterization .......................................................................................... 19 3.3.1. Bio-oil GC-MS ............................................................................................... 19 3.3.2. Bio-oil FTIR ................................................................................................... 24 ii 3.3.3. Calorific value determination ......................................................................... 25 3.3.4. Distillation curve ............................................................................................ 25 3.4. Biochar characterization ........................................................................................ 26 3.4.1. Elemental and HHV analysis .......................................................................... 26 3.4.2. Biochar FTIR .................................................................................................. 27 4. Conclusions .................................................................................................................. 28 5. Recommendations and future work .............................................................................. 29 6. References .................................................................................................................... 30 7. Annexes ........................................................................................................................ 36 7.1. Tubular pyrolysis statistical analysis ..................................................................... 36 7.1.1. Yields .............................................................................................................. 36 7.1.2. Mass losses ..................................................................................................... 38 2.1.1. Mass losses ..................................................................................................... 39 7.2. Laboratory scale pyrolysis ..................................................................................... 40 7.3. Bio-oils characterization ........................................................................................ 41 iii LIST OF FIGURES Figure 1. Tubular furnace system for small-scale pyrolysis ................................................... 5 Figure 2. Laboratory-scale pyrolysis equipment (0 = flowmeter, 1 = nitrogen inlet with 6 thermocouples, 2 = reactor chamber, 3 = first SS condenser, 4 = bio-oil amber jar, 5 = second condenser, 6 = heat exchanger, 7 = gas analyser, 8 = gas burner flame/extraction hood) ..... 7 Figure 3. Simple distillation equipment for distillation curve ................................................ 9 Figure 4. Biomass (Kernel and Shell) elemental composition and higher heating value ..... 10 Figure 5. Biomass FTIR analysis ......................................................................................... 11 Figure 6. Biomass TGA-DSC analysis ................................................................................. 12 Figure 7. Tubular furnace pyrolysis conversions ................................................................. 13 Figure 8. Mass Losses .......................................................................................................... 15 Figure 9. Biochar mass gain by factor .................................................................................. 16 Figure 10. Yield obtained in laboratory-scale pyrolyzes test ............................................... 16 Figure 11. Biogas analysis .................................................................................................... 18 Figure 12. TGA-DSC analysis for mass deposits ................................................................. 19 Figure 13. Bio-oils FTIR ...................................................................................................... 24 Figure 14. Bio-oils distillation curves .................................................................................. 25 Figure 15. Distillation curve of 4 alternative diesel fuels (Gough & Bruno, 2012) ............. 26 Figure 16. Biochar elemental analysis .................................................................................. 27 Figure 17. Biochar FTIR ...................................................................................................... 28 Figure 18. Main effects of temperature and biomass on bio-oil production yields .............. 36 Figure 19. Main effects of temperature and biomass on biochar production yields ............ 36 Figure 20. Main effects of temperature and biomass on biogas production yields .............. 37 Figure 21. Mean comparison of bio-oil production yield according to biomass by Sidak test .............................................................................................................................................. 37 Figure 22. Mean comparison of bio-oil production yield according to temperature by Sidak test ......................................................................................................................................... 37 Figure 23. Mean comparison of biochar production yield according to biomass by Sidak test .............................................................................................................................................
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