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Design of a Continuous-Flow, Immobilized-Cell Fermentor System for Production of Bioethanol

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Design of a Continuous-Flow, Immobilized-Cell Fermentor System for Production of Bioethanol Design of a Continuous-Flow, Immobilized-Cell Fermentor System for Production of Bioethanol by Lan Ma, B.S. Dissertation In Chemical Engineering Submitted to the Graduate Faculty of Texas Tech University in Partial Fulfillment of the Requirements for the Degree of Doctor of Philosophy Approved Dr. Ronald C. Hedden Chair of Committee Dr. M. Nazmul Karim Dr. Mark W. Vaughn Dr. Carla M. R. Lacerda Dr. Michael J. D. San Francisco Dr. W. Andrew Jackson Dr. Mark Sheridan Dean of the Graduate School December 2014 Copyright 2014, Lan Ma Texas Tech University, Lan Ma, December 2014 Acknowledgements First and foremost I want to thank my advisor Dr. Hedden for his support, advice and guidance during my doctoral study at Texas Tech University. I appreciate Dr. Hedden for introducing me to the areas of polymer and ethanol fuel. At the beginning of study, I was not even sure what polymer is, he expressed his confidence on me. I am very grateful to Dr. Hedden for the time, ideas and encouragements he gave to me, especially when I encountered difficulties and lost confidence during the research. It has truly been a privilege for me to be his student. I would like to thank Dr. Karim for his kindness in guiding my early study and allowing me to use his equipment. A special thank you goes to Dr. Lacerda who gave me a lot of valuable advices. I would also like to thank Dr. Vaughn, Dr. San Francisco and Dr. Jackson for being my dissertation committees. To my colleges, Dr. Jun Zhao, Dr. Huipeng Chen, Dr. Seunghyun Ryu, Ziniu Yu, Rutvik Godbole, Michael Sees and undergraduate students who worked in our laboratory, I am thankful for all your friendship, support and help. All my friends, you know how I appreciate your support and accompany. Finally, I could never complete my research without the love, support and encouragement of my parents, Ruiqing Ma and Shuqin Luan. I love you so much. ii Texas Tech University, Lan Ma, December 2014 Table of Contents Acknowledgements ............................................................................................................. ii Table of Contents ............................................................................................................... iii Abstract .............................................................................................................................. vi List of Tables ................................................................................................................... viii List of Figures .................................................................................................................... ix Chapter 1 Introduction ........................................................................................................ 1 1.1 Biofuel as a renewable fuel ....................................................................................... 1 1.2 Cellulosic Feedstocks ................................................................................................ 2 1.3 Development of ethanologenic microorganisms ....................................................... 7 1.3.1 Engineering and performance of E. coli ............................................................. 7 1.3.2 Engineering and performance of other microorganisms .................................... 9 1.3.3 Comparison of the microorganisms fermentation performance ....................... 11 1.4 Fermentation reactor design .................................................................................... 12 1.4.1 Continuous immobilized cell reactor design .................................................... 12 1.4.2 Immobilization scaffold materials and methods ............................................... 13 1.4.3 Immobilized cell reactor for EtOH production ................................................. 17 1.5 Bioethanol separation .............................................................................................. 19 1.6 Objectives and organization of this study ............................................................... 22 1.7 References ............................................................................................................... 26 Chapter 2 Batch and chemostat bio-ethanol fermentation process with strain Escherichia coli. LY01 ......................................................................................................................... 36 2.1 Introduction ............................................................................................................. 36 2.2 Materials and methods ............................................................................................ 40 2.2.1 Microorganism and growth medium ................................................................ 40 2.2.2 Inoculum preparation ........................................................................................ 40 2.2.3 Fermentation conditions ................................................................................... 41 2.2.3 Analytical methods ........................................................................................... 41 2.3 Results ..................................................................................................................... 42 2.3.1 Batch fermentations .......................................................................................... 42 2.3.2 Chemostat fermentaions ................................................................................... 50 iii Texas Tech University, Lan Ma, December 2014 2.4 Conclusion ............................................................................................................... 55 Chapter 3 Design of a continuous-flow, packed-bed fermentation process ..................... 59 3.1 Introduction ............................................................................................................. 59 3.2 Materials and methods ............................................................................................ 61 3.2.1 Segmented vertical column reactor and immobilized cell stirred tank reactor 61 3.2.2 Inoculum preparation ........................................................................................ 63 3.2.3 Analytical methods ........................................................................................... 63 3.3 Results and discussion ............................................................................................. 64 3.3.1 Cell immobilization with synthetic porous polymer scaffold (SPPS) .............. 64 3.3.2 Cell immobilization with poly(ethylene terephthalate) fiber scaffold.............. 79 3.4 Discussion ............................................................................................................... 96 3.5 Conclusion ............................................................................................................... 97 3.6 References ............................................................................................................... 99 Chapter 4 Kinetics study of ethanol fermentation with Escherichia coli. LY01 ............ 101 4.1 Batch fermentation kinetics ................................................................................... 101 4.1.1 General unstructured kinetic model ................................................................ 102 4.1.2 Models with growth inhibitors ....................................................................... 104 4.1.3 Kinetics model of ethanol production by E. coli LY01 .................................. 105 4.2. Continuous fermentation kinetics ........................................................................ 111 4.3. Mathematical modeling of cell immobilized fermentation with packed-bed column reactor at steady state .................................................................................................. 117 4.4 Dimensionless parameters estimation ................................................................... 126 4.5 Conclusion ............................................................................................................. 128 4.6 References ............................................................................................................. 131 Chapter 5 Combinatorial screening of selective materials for extractive fermentation . 133 5.1 Introduction ........................................................................................................... 133 5.2 Experimental section ............................................................................................. 136 5.2.1 Network synthesis........................................................................................... 136 5.2.2 Swelling experiments ..................................................................................... 137 5.2.3 Selectivity ....................................................................................................... 137 5.3 Theory and calculations (collaborated with Rutvik Godbole) .............................. 139 iv Texas Tech University, Lan Ma, December 2014 5.4 Results and discussion ........................................................................................... 144 5.4.1 Equilibrium swelling ...................................................................................... 144 5.4.2 Distribution coefficient and equilibrium selectivity ....................................... 147 5.4.3 Predicted distribution coefficient and selectivity from the model .................. 149 5.4.4 Diffusivities
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