A Dissertation entitled Chemistry and Chemical Engineering Process for Making PET from Bio Based Monomers by Damian Adrian Salazar Hernandez Submitted to the Graduate Faculty as partial fulfillment of the requirements for the Doctor of Philosophy Degree in Engineering _________________________________________ Dr. Saleh A. Jabarin, Committee Chair _________________________________________ Dr. Maria Coleman, Committee Member _________________________________________ Dr. Isabel Escobar, Committee Member _________________________________________ Dr. Sridhar Viamajala, Committee Member _________________________________________ Dr. Joseph Lawrence, Committee Member _________________________________________ Dr. Patricia R. Komuniecki, Dean College of Graduate Studies The University of Toledo December, 2015 Copyright 2015, Damian Adrian Salazar Hernandez This document is copyrighted material. Under copyright law, no parts of this document may be reproduced without the expressed permission of the author. An Abstract of Chemistry and Chemical Engineering Process for Making PET from Bio Based Monomers by Damian Adrian Salazar Hernandez Submitted to the Graduate Faculty as partial fulfillment of the requirements for the Doctor of Philosophy Degree in Engineering The University of Toledo December, 2015 Polyethylene terephthalate (PET) is a semicrystalline polymer widely used for production of fibers, films and containers. The polymer is obtained from the reaction of ethylene glycol (EG) and terephthalic acid (PTA) in a two stage process involving esterification and polycondensation reactions. Historically, the raw materials have been obtained from petro sources through refining of oil. To alleviate the dependence on fossil energy resources, researchers have synthesized EG and PTA starting from biomass. The use of these bio monomers depends on their suitability to polymerization requirements and the quality of the polymer that can be produced. In this research, PET was synthesized using both monomers obtained from a bio based source. Bio EG was obtained with a high purity and was used as received. Bio PTA was produced through a modified Amoco process using bio p-xylene separated through distillation and crystallization methods from a sample containing furans, aromatics and alkanes. The analysis of the separation methods revealed that the side products present in the bio p-xylene sample do not have equilibrium limitations that prevent their removal iii through physical separation methods. Bio p-xylene was obtained with purity enough to be considered a high grade product (~99.8%), Low concentration impurities in the form of alkanes and a furan molecule were still present in the product. The analysis of the production of PTA revealed that the furan impurity present in bio p-xylene did not oxidize under Amoco process conditions, the furan was recovered from the reaction media in the oxidation liqueur. When compared to the use of petro p- xylene, the PTA produced had similar characteristics evaluated through color measurements, optical density and product purity. Both materials were produced with concentration of monofunctional groups low enough for their use in the polymerization reaction. In order to disclose the effect on polymerization of using bio derived monomers, the analyses of product composition, thermal stability, crystallization behavior and physical properties were done. It was found that when the purity of the bio derived monomers is comparable to that of a petro product a polymer with similar characteristics was obtained. Based on the characteristics of the polymers produced, there was no assignable difference to the use of either set of raw materials. iv To my wife, Alejandra, you are the most important part of my life, my support, my reality, my love, my friend and my partner in crime. Thank you for being with me in this journey and for being so passionate, caring, and dedicated in your life. Para tí, por tí y contigo. Acknowledgements First, I would like to thank Dr. Saleh A. Jabarin for giving me this invaluable opportunity to be his student, for sharing his knowledge, for being always comprehensive and for his patience. I would like to thank DAK Americas LLC for funding my Ph.D. program at the University of Toledo. Special thanks to Dr. Peter Kezios for his continuous support and constructive criticism in my research work. Thank you to Alfredo Carrasco for believing in me and for his help in making this opportunity possible. I would like to thank Elizabeth Lofgren for her enormous help in the analytical experiments and for reviewing this work. Thank you to Mike Mumford for his help with the processing equipment and with experiments. Thank you to Dr. Maria Coleman, Dr. Joseph Lawrence, Dr. Isabel Escobar and Dr. Sridhar Viamajala for serving on my dissertation committee. Finally, I would like to thank my family for being there for me throughout these years and to all my friends at the University of Toledo for their support, friendship and for all those little details in our everyday that made these years so wonderful. ¡Gracias! vi Table of Contents Abstract .............................................................................................................................. iii Acknowledgments.............................................................................................................. vi Table of Contents .............................................................................................................. vii List of Tables ...................................................................................................................xv List of Figures .................................................................................................................. xxi 1 Introduction……………………………………………………………..………. 1 1.1 Polyethylene terephthalate (PET) overview ......................................................1 1.2 Research significance .........................................................................................5 1.3 Objectives .........................................................................................................6 1.3.1 Specific Objectives ............................................................................8 1.4 Organization of dissertation ..............................................................................9 2 Literature Review ................................................................................................12 2.1 PET synthesis – melt phase polymerization ....................................................12 2.1.1 The role of catalyst on PET synthesis ...............................................19 2.1.2 Formation of byproducts ...................................................................21 2.2 Degradation of PET .........................................................................................23 2.2.1 Thermal degradation of PET .............................................................23 2.2.2 Hydrolytic degradation of PET .........................................................24 2.2.3 Thermal-oxidative degradation of PET ............................................25 vii 2.3 Production of petro based raw materials ..........................................................27 2.2.1 Petro ethylene glycol.........................................................................27 2.3.2 Petro p-xylene ...................................................................................29 2.3.3 Petro terephthalic acid.......................................................................33 2.3.3.1 Amoco process ...................................................................34 2.4 Production of bio based raw materials ............................................................42 2.4.1 Biomass composition .......................................................................42 2.4.2 Ethylene glycol ................................................................................45 2.4.2.1 Production from bio ethanol .............................................45 2.4.2.2 Production from sorbitol ...................................................46 2.4.3 Terephthalic acid ..............................................................................47 2.4.3.1 Production from oxygenated compounds ..........................47 2.4.3.2 Production from 5-hydroxymethylfurfural (HMF) ............49 2.4.3.3 Production from limonene .................................................52 2.4.3.4 Production from isobutanol................................................53 2.4.3.5 Production from muconic acid ...........................................54 2.4.3.6 Production from ethylene ...................................................55 2.4.3.7 Production from 2,5 furan dicarboxylic acid (FDCA) .......56 2.4.3.7.1 Polyethylene furanoate (PEF) .............................57 2.4.3.8 Production from lignin .......................................................59 3 Experimental ........................................................................................................60 3.1 Materials…. .....................................................................................................60 3.2 Analytical techniques .......................................................................................63 viii 3.2.1 Gas Chromatography with flame ionization detector (GC-FID) ......62 3.2.2 Gas Chromatography mas spectroscopy (GC-MS)...........................64 3.2.3 Reversed phase liquid chromatography