Hydrothermal Reactions of Algae Model Compounds by Shujauddin M. Changi A dissertation ...

194 Pages·2012·4.79 MB·English

Hydrothermal Reactions of Algae Model Compounds
by
Shujauddin M. Changi

A dissertation submitted in partial fulfillment
of the requirements for the degree of
Doctor of Philosophy
(Chemical Engineering)
in The University of Michigan
2012

Doctoral Committee:

Professor Phillip E. Savage, Chair
Professor Adam J. Matzger
Assistant Professor Charles W. Monroe
Adjunct Professor Shawn E. Hunter
© Shujauddin M. Changi
2012
To my parents, Munira and Mohsin
and my wife, Nazneen
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Acknowledgments

I thank my advisor Professor Phillip E. Savage who has always been there
whenever needed throughout the course of my PHD. His clarity of thought,
recommendations, suggestions, and criticisms have greatly added to my
personal and professional development. His mentorship has gone a long way in
helping me successfully write this dissertation.
I also acknowledge my other committee members, Professor Adam J.
Matzger, Assistant Professor Charles W. Monroe, and Adjunct Professor Shawn
E. Hunter for their valuable advice and suggestions during the course of this
PHD. Discussions with them have helped shape this dissertation the way it is.
I am grateful to former group members, Tanawan Pinnarat, Tylisha Brown,
and Minghan Zhu, who have also co-authored with me on different manuscripts. I
learned a lot from each of them by working on different projects. I would also like
to thank current group members Robert Levine and Peter Valdez for help in
training to use GC-FID and Jacob Dickinson for useful discussions in MATLAB
coding. I also thank Apurva Lingnuarkar, my mentee, whose experiments helped
me finish my work smoothly and quickly.
I acknowledge other former Savage group members, Peigao Duan,
Natalie Rebacz, Jie Fu, Qingqing Guan, Dongil Kang and current group members
including Zheng Li, Chad Huelsman, Thomas Yeh, Allison Franck, Tiffany Mo,
Julia Faeth, and Yang Guo for their help, advice and suggestion at some point or
the other.

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I would like to thank Susan Hamlin for taking care of all the administrative
matters and paperwork. I acknowledge Claire O’Connor, Shelly Fellers, Michael
Africa, Laurel Neff, and Connie Raymond for taking care of all the departmental
issues.
I acknowledge the NSF Grant – EFRI 0937992 for financial support in
carrying out this research.
I thank my distant family members living in Ann Arbor, my friends:
Priyanka Pande, Nasim Balou, Lilian Hsiao, Priska Poan, Elizabeth Stewart,
Andiappan Marimuthu, Ines Pons, Nick Stuckert, Matthew Morabito, Khamir
Mehta, Mohammad Sichani, Adam Patterson, Muhammad Murshed Khadija, and
my Northwood Community Apartment neighbors, all of whom have made my life
enjoyable throughout my PHD. I am grateful to my friend Amey Bandekar for
being with me through the ups and downs in this journey.
I am indebted to all my professors throughout my Bachelor’s degree at
Institute of Chemical Technology (formerly U.D.C.T.) (especially Prof. G. D.
Yadav and V. C. Malshe), my Master’s degree at Massachusetts Institute of
Technology and my PHD degree at University of Michigan for teaching me
different subjects and helping me develop the foundations in chemical
engineering.
I am very grateful to my mentors Winnie Torres-Ordoñez, Craig Colling,
and Ramachandra Surve, who have helped me constantly be motivated and
achieve success in life. I thank all my relatives back in India for their love and
support throughout. I am grateful to my in-laws (Fakhera, Khozema, and Hussain
GIttham) whose care and support have gone a long way in my PHD. I thank my
wife Nazneen for being by my side and being my strength through thick and thin.
Finally, I owe everything to my parents (Munira and Mohsin Changi) whose love,
emotional support, encouragement, sacrifice and advice have helped me travel
and complete the journey of obtaining a PHD.

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Table of Contents

Dedication………………………………………………………………………ii
Acknowledgements……………………………………………………………iii
List of Figures………………………………………………………………….viii
List of Tables…………………………………………………………………..xi
List of Appendices…………………………………………………………….xiii
Abstract………………………………………………………………………...xiv
Chapter
1. Introduction…………………………………………………………1
1.1 Motivation……………………………………………….1
1.2 Relevance to Sustainability…………………………...3
1.3 Composition of Algae………………………………….4
1.4 Selection of Model Compounds……………………...8
2. Literature Review…………………………………………………17
2.1 Ethyl Oleate…………………………………………...17
2.2 Phenylalanine……………..…………………………..21
2.3 Phytol………………..…………………………………24
2.4 DOPC…………………………..……………………...25
2.5 Binary Mixtures……………………………………….27
2.6 Summary of Gaps in Literature……………………..29

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3. Experimental Setup……………………………………………….38
3.1 Materials….…………………………………………….38
3.2 General Experimental Setup………………………....39
3.3 Individual Model Compound Experimental Setup….40
4. Behavior of Ethyl Oleate in HTW………………………………...52
4.1 Control Experiment….………………………………...52
4.2 Effect of Reaction Conditions…..…………………....53
4.3 Phenomenological Autocatalytic Kinetics…………..57
4.4 Mechanistic Autocatalytic Kinetics…………………..66
4.5 Conclusions…………………………………………....80
5. Behavior of Phenylalanine in HTW………………………………84
5.1 Control Experiment….…………………………………84
5.2 Effect of Reaction Conditions….……………………..84
5.3 Kinetics of Phenylalanine Disappearance…...……...88
5.4 Reaction Pathways……………….……………………89
5.5 Kinetic Model…………………………………………...93
5.6 Conclusions…………………………………………….96
6. Behavior of Phytol in HTW………………………………………100
6.1 Control Experiment….……………………………….100
6.2 Effect of Reaction Conditions….……………………101
6.3 Kinetics of Phytol Disappearance…………...……..107
6.4 Reaction Pathways……………….………………….108
6.5 Kinetic Model………………………………………….114
6.6 Conclusions…………………………………………...119
7. Behavior of DOPC in HTW……………………………………...124
7.1 Control Experiment….……………………………….124
7.2 Effect of Reaction Conditions….……………………124
7.3 Reaction Pathways……………….…………...……..130
7.4 Phenomenological Autocatalytic Kinetics………….135
7.5 Kinetic Model………………………………………….138
7.6 Conclusions…………………………………………...143

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8. Behavior of Binary Mixtures in HTW…………………………...146
8.1 Control Experiment….……………………………….146
8.2 Binary Mixtures of Inorganics and Phenylalanine...147
8.3 Binary Mixture of Ethyl Oleate and Phenylalanine..149
8.4 Conclusions…………………………………………...165
9. Implications, Conclusions, and Future Work………………….169
Appendices……………………………………………………………………176
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List of Figures

Figure
1.1 Properties of pure water at 250 bar as a function of temperature…2
1.2 Chemical structure of chlorophyll a…...……………………………...7
4.1 Temporal variation of ethyl oleate conversion ……………………..54
4.2 Parity plot of phenomenological model for hydrolysis
experiments…………………………………………………………….61
4.3 Parity plot of phenomenological model validation for experiments
conducted inside and outside parameter space……………………62
4.4 Mechanism explaining autocatalysis for ethyl oleate hydrolysis
and oleic acid esterification……………………………………………67
4.5 Schematic representation of hydrolysis and esterification
mechanism……………………………………………………………...69
4.6 Schematic representation of simplified hydrolysis and esterification
mechanism……………………………………………………………...72
4.7 Parity plot of mechanistic model for hydrolysis experiments……...74
4.8 Parity plot of mechanistic model validation for experiments
conducted inside and outside parameter space……………………76
4.9 Model validation at different pH for ethyl oleate hydrolysis at
280 °C and 40 min………..……………………………………………77
5.1 LC-MS chromatograms for phenylalanine reaction products at
different conditions……………………………………………………..92
5.2 Reaction pathways for phenylalanine in HTW………………………92
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5.3 Comparison of experimental (discrete points) and model (smooth
curves) results for reactants and products at different
conditions………………………………………………………………..95
5.4 Parity plot between experimental and model concentration……….96
6.1 Total ion chromatogram for the product mixture obtained from the
hydrothermal reaction of phytol 300 °C and 20 min………………101
6.2 Representative MS fragmentation pattern of neophytadiene……103
6.3 First-order plot for phytol conversion in HTW……………………...108
6.4 First-rank Delplot at 270 °C for different products………...……....109
6.5 Reaction network for phytol in HTW………………………………..113
6.6 Simplified reaction network for kinetic modeling of phytol in
HTW……………………………………………………………………114
6.7 Comparison of experimental (discrete points) and model (smooth
curves) results for reactants and products at different
conditions……………………………………………………………...118
6.8 Parity plot between experimental and model concentration for
reactant and products………………………………………………..119
7.1 31P-NMR spectrum of products from DOPC reaction at 200 °C
and 60 min……………………………………………………………125
7.2 Temporal variation of DOPC conversion…………………………..129
7.3 Parity plot for comparison of experimental and model concentration
for DOPC…………….…..……………………………......................137
7.4 Parity plot for comparison of experimental and model concentration
for oleic acid………...……………………………............................138
7.5 Streamlined reaction network for DOPC in HTW…………………139
7.6 Comparison of experimental and calculated concentrations at
175 °C, 200 °C, 225 °C, and 350 °C……………………………….143
8.1 Effect of salts and boric acid on phenylalanine at 250 °C and
30 min in HTW………………………………………………………..148
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