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Conversion of glycerol to the valuable intermediates acrolein and allyl alcohol in the presence of heterogeneous catalysts [Elektronische Ressource] / vorgelegt von Arda Ülgen

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Conversion of glycerol to the valuable intermediates acrolein and allyl alcohol in the presence of heterogeneous catalysts Von der Fakultät für Mathematik, Informatik und Naturwissenschaften der RWTH Aachen University zur Erlangung des akademischen Grades eines Doktors der Naturwissenschaften genehmigte Dissertation vorgelegt von Diplom-Chemiker Arda Ülgen aus Istanbul Berichter: Universitätsprofessor Dr. Wolfgang F. Hölderich sprofessor Dr. Manfred Martin Tag der mündlichen Prüfung: 14.09.2009 Diese Dissertation ist auf den Internetseiten der Hochschulbibliothek online verfügbar. For my beloved father Dr. Remzi Ülgen This work was carried out between September 2005 and July 2008 at the Chair for Chemical Technology and Heterogeneous Catalysis at the RWTH Aachen University. Parts of this thesis have been published or submitted for publication. I would like to express my sincere thanks to Prof. Dr. Hölderich for providing the interesting topic, outstandingly good working conditions, for his advice, inspiration and for the freedom of research which I always appreciated. Prof. Dr. Martin, I thank for his kind assumption of the co-reference. I would like to thank to the company Arkema S.A. for its financial support. The fruitful discussions with Dr. Kervennal, Dr. Dubois, Dr. Devaux, Dr. Teissier, Dr. Linemann, Ms. Serreau, Dr. Fauconet, Dr. Tretjak and Dr. Haller from Arkema S.A.
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Conversion of glycerol to the valuable
intermediates acrolein and allyl alcohol in
the presence of heterogeneous catalysts

Von der Fakultät für Mathematik, Informatik und Naturwissenschaften der RWTH
Aachen University zur Erlangung des akademischen Grades eines Doktors der
Naturwissenschaften genehmigte Dissertation

vorgelegt von

Diplom-Chemiker
Arda Ülgen
aus Istanbul

Berichter: Universitätsprofessor Dr. Wolfgang F. Hölderich sprofessor Dr. Manfred Martin
Tag der mündlichen Prüfung: 14.09.2009

Diese Dissertation ist auf den Internetseiten der Hochschulbibliothek online verfügbar.

For my beloved father Dr. Remzi Ülgen













This work was carried out between September 2005 and July 2008 at the Chair for
Chemical Technology and Heterogeneous Catalysis at the RWTH Aachen University.
Parts of this thesis have been published or submitted for publication.
I would like to express my sincere thanks to Prof. Dr. Hölderich for providing the
interesting topic, outstandingly good working conditions, for his advice, inspiration
and for the freedom of research which I always appreciated.
Prof. Dr. Martin, I thank for his kind assumption of the co-reference.
I would like to thank to the company Arkema S.A. for its financial support. The fruitful
discussions with Dr. Kervennal, Dr. Dubois, Dr. Devaux, Dr. Teissier, Dr. Linemann,
Ms. Serreau, Dr. Fauconet, Dr. Tretjak and Dr. Haller from Arkema S.A. were always
encouraging me throughout my studies.
Special thanks to Dr. Sabater, for the engineering support, constant help and
advices. I also like to thank to Mr. Vaessen and Ms. Biener, for the catalyst
characterization measurements.
I owe many thanks to the research students, Mr. Schill, Mr. Sopgwi and Ms. Tulimat,
for their energetic engagement.
I would like to thank all technicians, all my friends with whom I have shared the
laboratory for their help and support.
I am very grateful to my family, especially to my father who gave me continuous
support and encouragement during my studies.
Table of contents
A INTRODUCTION................................................................................................. 1
1 Scope of the work ............................................................................................ 1
2 The motivation 2
B BASIC KNOWLEDGE ......................................................................................... 6
1 Green chemistry and heterogeneous catalysis ................................................ 6
2 Relevant compounds ..................................................................................... 10
2.1 Glycerol .................................................................................................. 10
2.2 Acrolein................................................................................................... 18
2.3 Ally alcohol ............................................................................................. 23
3 Heterogeneous catalysts used in this work.................................................... 26
4 Brief information about techniques and reactors used in the work................. 30
C STATE OF THE ART......................................................................................... 33
D RESULTS AND DISCUSSION .......................................................................... 36
1 Zirconia based catalysts ................................................................................ 36
1.1 Tungstated zirconia 37
1.1.1 Commercial catalysts ...................................................................... 37
1.1.1.1 Preliminary experiments .............................................................. 38
1.1.1.2 Studies on the catalyst properties and its effect on the reaction.. 45
1.1.2 Self made WO /ZrO catalysts......................................................... 53 3 2
1.2 Heteropolytungstate on zirconia ............................................................. 55
1.3 Sulfated zirconia ..................................................................................... 56
1.4 A global view on acidity and basicity for zirconia catalysts ..................... 58
1.5 Cerium oxide on zirconia ........................................................................ 63
1.6 Reaction route studies with tungstated zirconia catalysts....................... 65
1.6.1 Statistical studies............................................................................. 65
1.6.2 Products applied as main reactants................................................. 69
1.6.3 Summary: The reaction route of glycerol dehydration ..................... 72
1.6.4 Formation of propionaldehyde......................................................... 74
1.6.5 Formation of acetaldehyde .............................................................. 77
1.6.6 The formation of acetol.................................................................... 78
1.6.7 Formation of other products............................................................. 78
2 Titania based catalysts .................................................................................. 79
2.1 Titania carriers without loading ............................................................... 80
I Table of contents
2.2 Influence of WO amount on Hombikat Typ II based catalysts ............... 82 3
2.3 Influence of temperature over 17,8 wt. % WO /TiO (Hombifine N)........ 86 3 2
2.4 Variation of titania carriers and influence of oxygen ............................... 87
2.5 Influence of calcination temperature....................................................... 91
2.6 Comparison of P-WO and WO ............................................................. 92 3 3
2.7 Comparison of different catalysts in the long term runs .......................... 93
2.8 Multi-component catalysts ...................................................................... 96
3 Studies for the production of allyl alcohol 99
E SUMMARY AND OUTLOOK ............................................................................101
F EXPERIMENTAL PART ...................................................................................105
1 Chemicals .....................................................................................................105
2 Catalyst preparation......................................................................................105
3 Reactor set-up and catalyst screening..........................................................106
4 Analysis ........................................................................................................109
4.1 Catalyst characterization .......................................................................109
4.1.1 Qualitative product analysis............................................................109
4.1.2 Quantitative product analysis..........................................................110
G APPENDIX .......................................................................................................122
1 Catalyst numbers..........................................................................................122
2 Experiment parameters.................................................................................123
3 Detailed experimental results........................................................................126
H REFERENCES.................................................................................................131



II Table of abbreviations
Å Angstrom
Acr Acrolein
Al. Alc. Allyl alcohol
BET Brunauer, Emmett and Teller
Calc. Calcined, calcination
CAS Chemical abstracts service
Cat. Catalyst
et al. et alii
Me Methyl
MeOH Methanol
Exp. Experiment
FID Flame ionization detector
Gly Glycerol
h Hour
Het. Heterogeneous
i.e. id est
ICP Inductive couple plasma
Min. Minimum, minute
mt Metric tons
mln Milliliter under normal conditions
N/A Not available
p Page
PSD50 Particle size distribution, 50 %
S Selectivity
scCO Super critical carbon dioxide 2
T Temperature
TCD Thermal conductivity detector
TPD programmed desorption
wt. % Weight percent
X Conversion
Y Yield

III Introduction
A INTRODUCTION
1 Scope of the work
The aim of the present work is the investigation of heterogeneously catalyzed
continuous conversion of glycerol out of the biodiesel production to the valuable
intermediates acrolein and allyl alcohol in the gas phase. In the case of acrolein, the
reaction is basically the elimination of two molecules of water from glycerol thus can
be also referred as dehydration.

Figure 1: The investigated reaction; dehydration of glycerol to acrolein.
In the case of allyl alcohol, the stoichiometric equation is given in figure 2.

Figure 2: The investigated reaction; dehydration of glycerol to allyl alcohol.
The development of suitable catalysts, screening of these catalysts under different
experimental conditions, as well as investigation of the reaction route, the side
products and relationships between the properties of the catalysts and their
performance in particular on the acrolein formation represent the scope of this work.
The conversion of glycerol to allyl alcohol was discovered and will be handled
separately.
1 Introduction
2 The motivation
The approach to the motivation of the present work can be done in two aspects. On
one hand, there are aspects of environmental responsibilities and on the other hand
there are economical impulses. These two motivations go hand in hand and
presented hereby as such.
Global warming, increasing oil prices and rising daily costs as well as environmental
pollution became very familiar keywords in the last decade. They are not only sole
problems for the humanity, but also the roots of these problems and their solutions
are connected.
Crude oil, natural gas and coal represent the basis of current industrial organic
[1]chemistry. On one hand these feedstocks are used for the production of energy in
terms of combustion, on the other the chemical industry has increasing demand on
these fossil resources due to rising production, correlated to world population. The
contest between these two huge industries escalates the prices of the valuable
carbon sources.
Beside the economical aspects, the problem has also environmental facets. Soon or
later each carbon atom extracted from the mentioned sources ends up its journey by
oxidation. Carbon dioxide is accepted to be one of the main actors in the global
[2]warming.
Sustainable development represents a global approach to the mentioned problems.

„Sustainable development meets the needs of the present generations without
[3]compromising the ability of future generations to meet their own needs”

The sake of sustainability and the skyrocketing prices as well as anticipated scarcity
of fossil resources have put pressure on many chemical companies to switch from
fossil-derived feed stocks to (still often much cheaper) renewable ones.
2 Introduction
Plants with high oil content (i.e. palm- rapeseed- or sunflower oil) are in the focus of
the renewable feedstock research. The oils extracted from these plants are used for
the production of bio-diesel. The combustion of the diesel fuel, where the carbon
atoms are originated from the mentioned plants, is considered to be environmentally
benign, since the process does not emit new carbon atoms to the atmosphere, but
only the ones which the plants absorbed during photosynthesis.
During the production of bio-diesel, glycerol is produced as an inevitable by-product.

Figure 3: The trans esterification process for the production of bio-diesel. The methyl esters of
[4]
the fatty acid are used as fuel for diesel engines. Glycerol is the by-product of the process.
The increasing output of bio-diesel led to an overproduction of glycerol. For each
[5]100 kg of bio-diesel, 10 kg of glycerol is given out. The oversupply of glycerol by
means of oleo-chemistry did not only make the classical production of glycerol
unnecessary, but also loaded extra costs on the bio-diesel producers in terms of
[6]storage. The so produced glycerol is polluted with oils, salts and additionally it is
diluted with water. But only pure glycerol is demanded by the food, pharma or
tobacco industry, where it is used as starting materials or as additives. New
processes are searched eagerly, where the usage of crude bio-diesel glycerol is
[6]possible.
Acrolein, on the other hand, is an important intermediate in the organic industrial
chemistry. More than 80 % of refined acrolein is used for the production of methionin.
Much larger quantities of crude acrolein are produced as an intermediate during the
production of acrylic acid. 85 % of the acrylic acid is produced by the captive
oxidation of acrolein. Acrylic acid is polymerized further to poly acrylic acid, which is
the main component of superabsorbers. These materials are widely used in diapers,
hygienic pads and paints. Acrolein is currently produced by the oxidation of
3 Introduction
propylene, which makes itself, the methionin, the acrylic acid, the polyacrylic acid and
[7]all other sequent compounds, crude oil based materials.
Another intermediate with increasing application areas is allyl alcohol. It is used for
the production of epicholorohydrine, allyl diglycol carbonate, allyl glycid ether, allyl
methacrylate, triallylcyanurate and especially 1-4 butanediol as starting material. Allyl
alcohol is produced from crude oil based materials (for example propylene) as in the
[8]case of acrolein.
The goal of this work is the development of suitable catalysts for the production of
valuable acrolein and allyl alcohol from overproduced glycerol. Shifting the source of
carbon for the production of these chemicals from propylene to glycerol would not
only encourage bio-diesel producers by enabling commercial possibilities for their by-
product, but it would also avoid using crude oil in the production of acrolein and allyl
alcohol. By that, acrolein, allyl alcohol and mentioned sequent chemicals would be
biomass based and a CO -neutral production would be provided. 2
The worldwide increasing glycerol production due to increasing biodiesel production
based on triglycerides and the steady demand on glycerol suppressed its price.
Contrasting the price of propylene with the price of glycerol underlines the
economical motivation of the present work.
2000
PRPROOPPYYLLEENNEE
1500 STANDARD
GLYCEROL
VEGETABLE
1000 GLYCEROL
TTAALLOLLOWW
GLYCEROL500
0
8989 9911 9393 9595 9797 9999 0101 0303 0505
YYearear
[9]
Figure 4: Proplylene and glycerol prices in Europe per metric ton. The price comparison
should be done under the consideration that each glycerol molecule includes two oxygen
atoms, which will be eliminated as water during its conversion to acrolein. This is not the case
for propylene, which makes it more efficient in terms of mass per product.
4
Prriicce ine in Europe (€/m/mTT))

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