KINETIC MODEL TO CATALYTIC KETONIZATION OF CARBOXYLIC ACIDS
OVER ZIRCONIUM OXIDE (ZrO2) IN THE MIXALCO® PROCESS
Degree Project
By
PEDRO FELIPE HUERTAS VARGAS
Submitted to the office of Graduate Studies of
Universidad de los Andes
In partial fulfillment to the requirements for the degree of
B.S. CHEMICAL ENGINEERING
Advisor
ROCIO SIERRA, M.Sc, Ph.D
UNIVERSIDAD DE LOS ANDES
ENGINEERING FACULTY
CHEMICAL ENGINEERING DEPARTMENT
BOGOTA D.C
2011
KINETIC MODEL TO CATALYTIC KETONIZATION OF CARBOXYLIC ACIDS
OVER ZIRCONIUM OXIDE (ZrO2) IN THE MIXALCO® PROCESS
Degree Project
By
PEDRO FELIPE HUERTAS VARGAS
____________________________________________
ROCÍO SIERRA RAMÍREZ, M.Sc., Ph.D
Advisor
_____________________________________________
CAMILA CASTRO, M.Sc.
Committee member
UNIVERSIDAD DE LOS ANDES
ENGINEERING FACULTY
CHEMICAL ENGINEERING DEPARTMENT
BOGOTA
2011
iii
ABSTRACT
Kinetic model to catalytic ketonization of carboxylic acids over zirconium oxide (ZrO2)
in the MixAlco® process
Pedro Felipe Huertas Vargas, Universidad de los Andes, Colombia.
Advisor: Rocío Sierra Ramírez, PhD
The goal of this project was to develop a kinetic model for catalytic ketonization
of carboxylic acids at a laboratory scale. The acids were obtained from acetic acid
reactant. In order to perform the ketonization, a packed-bed catalytic reactor using metal
oxide catalysts, specifically zirconium oxide, was used. The conditions used were:
pressure (14.696 psi, 100 psi, 200 psi and 400 psi), temperatures (573 K, 623 K, 673 K y
723 K) and flow feed rate (0.0002 L/min, 0.0004 L/min, 0.0006 L/min, 0.0008 L/min,
and 0.001 L/min) where the optimal conditions of operation found were: pressure 14,696
psi, temperature 723 K and an initial flow range between 0.2 y 0.6 mL/min. With this
data, it was determined that the controlling stage of the reaction is the surface reaction.
The influence of the studied variables was shown in the conversion achieving an optimal
range of operation. Finally, the initial parameters of the kinetic model based on the
thermodynamic functions of each component were estimated. This data was optimized
through the program MATLAB where the final parameters were obtained and therefore
the kinetic model.
iv
RESUMEN
Modelo cinético para la cetonización catalítica de ácidos carboxílicos sobre oxido de
zirconio (zro2) en el proceso MixAlco®.
Pedro Felipe Huertas Vargas, Universidad de los Andes, Colombia.
Asesora: Rocío Sierra Ramírez, PhD
El objetivo de este proyecto fue desarrollar un modelo cinético para la
cetonización catalítica de ácidos carboxílicos a una escala de laboratorio. Los ácidos se
obtuvieron alimentando acido acético como reactivo. Para realizar la cetonización se usó
un reactor catalítico empacado con óxidos metálicos como el oxido de zirconio como
catalizador, las condiciones usadas fueron: presión (14.696 psi, 100 psi, 200 psi y 400
psi), temperatura (573 K, 623 K, 673 K y 723 K), y flujo de alimentación (0.0002 L/min,
0.0004 L/min, 0.0006 L/min, 0.0008 L/min, y 0.001 L/min), donde las condiciones
optimas de operación encontradas fueron: presión 14,696 psi, temperatura 723K y un
rango de flujo inicial entre 0.2 y 0.6 mL/min. Con estos datos se determinó que la etapa
controlante de la reacción es la reacción de superficie. Se comprobó la influencia de las
variables estudiadas en la conversión logrando un rango óptimo de operación.
Finalmente, se estimaron los parámetros iniciales del modelo cinético basados en las
funciones termodinámicas de cada componente, estos datos fueron optimizados a través
del programa MATLAB, obteniéndose así los parámetros finales y por lo tanto el
modelo cinético.
v
DEDICATION
I dedicate this work to God,
my parents and my sister.
To God because He is my hope
and inspiration every day;
to my parents because
they have given up everything for me
and never doubted me;
and to my sister
because without her
none of what I have or am would be possible.
I love them
vi
ACKNOWLEDGEMENTS
I would like to thank God for giving me guidance and support to help me finish this
work. I have received great satisfaction in my personal and professional development
from him.
Thanks also to Dr. Mark T. Holtzapple, for the great opportunity to be part of your team,
and have the best technology and constant collaboration to develop the project. I am
especially grateful to Dr Rocío Sierra for her unconditional support both academic and
staff. The excellent results of this work are due to her leadership and commitment to
research.
I would also like to thank to the MixAlco® research group, especially Sebastian Taco
for their valuable advice. Thanks also to the entire Chemical Engineering Department at
Texas A&M.
Finally, I would like to thank my family, my great new friends in College Station: David
Serna, Amanda Niermann, Sandra Palomino, Camila Peña and Pablo Garcia, and my
friends here in Colombia, who with their unconditional support were a motivation for the
development of this project.
vii
TABLE OF CONTENTS
DEDICACIÓN .................................................................¡Error! Marcador no definido.
ACKNOWLEDGEMENTS .............................................¡Error! Marcador no definido.
LIST OF FIGURES ..........................................................¡Error! Marcador no definido.
LIST OF TABLES ............................................................................................................ ix
1. INTRODUCTION .......................................................................................................... 1
2. OBJECTIVES ................................................................................................................ 6
2.1. GENERAL OBJECTIVES ...................................................................................... 6
2.2. SPECIFIC OBJETIVES .......................................................................................... 6
3. LITERATURE REVIEW ............................................................................................... 7
3.1. Highlights ................................................................................................................ 7
3.2 Ketonization ............................................................................................................. 8
3.3. Kinetic model ........................................................................................................ 16
3.3.1 Adsoption ........................................................................................................ 18
3.3.2 Desorption ....................................................................................................... 19
3.3.3 Surface reaction ............................................................................................... 20
3.4 Catalyst ................................................................................................................... 25
3.4.1 Fourier Transform Infrared (FTIR): ............................................................... 25
3.4.2 Temperature Programmed Desorption (TPD): ................................................ 27
4. METHODOLY ............................................................................................................. 29
4.1 Research plan ......................................................................................................... 29
viii
4.2 Experimental procedure ......................................................................................... 30
4.3 Catalyst preparation ................................................................................................ 32
4.4 Experimental design ............................................................................................... 33
5. RESULTS AND ANALYSIS ...................................................................................... 34
5.1 Conversion ............................................................................................................. 34
5.2 Selectivit ................................................................................................................. 41
5.3 Kinetic model ......................................................................................................... 45
5.3.1 Initial parameter estimation ............................................................................. 47
6. CONCLUSIONS .......................................................................................................... 53
REFERENCES ................................................................................................................. 55
APPENDIX A .................................................................................................................. 61
APPENDIX B .................................................................................................................. 61
APPENDIX C .................................................................................................................. 64
APPENDIX D .................................................................................................................. 84
ix
LIST OF FIGURES
FIGURE PAGE
1 Overview of routes to chemical and fuel products via the carboxylate platform 2
2 Molecular interaction of acetic acid 3
3 Diagram of MixAlco Process 4
4. Schematic diagram of a process for converting biomass to liquid secondary
alcohol fuel [1].
6
5. Schematic diagram of a thermal conversion acid to ketone [1]. 10
6. Gas phase catalyst ketonization of carboxylic acids 12
7. Influence of concentration of active phase upon catalytic activity of CeO2/SiO 14
8. Catalytic activity of 20 wt.-% CeO2/SiO2 system in ketonization of acetic
acid at various LHSV. Reaction selectivity > 96%.
15
9. Graph conversion - space time. 17
10. Adsorption: controlling stage in the process. Initial velocity –total pressure. 18
11. Desorption: controlling stage in the process. Initial velocity–total pressure. 18
12. Surface reactions: controlling stage in the process. Initial velocity –total
pressure.
19
13. Reactor step used for the reaction kinetics experimental studies. 21
14. Ketonization reaction rates for varying partial pressures of hexanoic acid
using 2-butanone as solvent at 547 K, 572 K, 597 K and 623 K.
22
x
15. Experimental data and simulation results for ketonization, partial pressure of
hexanoic varied.
23
16. Packed Bed Reactor 28
17. Schematic diagram of the oligomerization process 29
18. Conversion of ketonization reaction for varying t space-time of feed at
different temperature values and a total pressure of 14.696 psi
35
19. Conversion of ketonization reaction for varying t space-time of feed at
different temperature values and a total pressure of 100 psi
37
20. Conversion of ketonization reaction for varying t space-time of feed at
different temperature values and a total pressure of 200 psi
39
21. Conversion of ketonization reaction for varying t space-time of feed at
different temperature values and a total pressure of 300 psi
40
22. Concentration of ketones on the product for varying temperature at low -
WHSV
42
23. Concentration of ketones on the product for varying temperature at high –
WHSV
43
24. Controlling stage 44
25. Arrhenius Graphic (Christian, 2009). 48
26. Comparison of experimental results with theoretical calculations obtained
from kinetic model.
49
xi
LIST OF TABLES
TABLE PAGE
1. Initial dates 33
2. Conversion results at pressure 14.696 psi 33
3. Conversion results at pressure 100 psi 36
4. Conversion results at pressure 200 psi 39
5 Conversion results at pressure 300 psi 40
6. Constants for the calculation of enthalpy (C.L, 2003) 46
7. Constants for the calculation of the Gibbs free energy (C.L, 2003) 46
8. Entropy calculated 47
9. Initial parameters 48
10. Final parameters for the kinetic model. 49
1
1. INTRODUCTION
Our planet is suffering serious environmental and energetic problems. This reality calls
for the development of new technologies that give priority to contamination prevention,
efficient power supply and usage, and optimal use of existing resources. In addition to
satisfying all of these requirements, new biofuel generations are required to use
feedstocks that are not food resources.
“Biofuels” are fuels derived from renewable resources such as crops, firewood, manure,
industrial and agricultural residues, microbial biomass and others.
Due to the last advances in biofuel research, there are different and new processes of
biofuel production involving the combination of biological and chemical processes.
One of them is the MixAlco Process developed by Dr. Mark Holtzaple at the Chemical
Engineering Department of Texas A&M University. A diagram including major stages
of the MixAlco process is depicted in Figure 3. This technology converts feedstock
residues into useful chemicals such as carboxylic acids and ketones.
1.1 Ketonization
The ketones are one of the products of the carboxylate platform; the resulting ketones
are converted to alcohols, which may be used as transportation fuels.
2
Figure 1. Overview of routes to chemical and fuel products via the carboxylate
platform
Ketones may be obtained from carboxylic acids or salts by thermal decomposition or
by catalysis. The reaction is:
(1)
Thermal conversion (not considered in this study) is a process involving precipitating
metal salts of volatile fatty acids (VFAs) by means of a heat transferred agent which
can be present in the reacting media in hollow (steel, glass or ceramic) balls that are
filled with a substance that melts at the temperature of thermal decomposition of VFAs.
3
As the temperature increases and the VFAs thermally decompose the reaction specified
in Eq. 1 takes place, resulting in ketones (vapor) and metal carbonate salts mixed with
the heat transfer agent.
Once the reaction is complete, the metal carbonate residue and heat transfer agent can
be removed to a lock hopper which has previously evaporated to vacuum. The metal
carbonate and heat transfer agent will have interstitial ketones vapors which are
removed using a vacuum pump and sent to a condenser for recovery (Holtzapple, 1999)
The method of interest for the purposes of this study is the catalytic conversion, which
uses direct ketonization of carboxylic acids in the gas phase over solid under flowing
conditions to the synthesis of ketones. The catalyst is maintained at the lowest reaction
temperature for 60 min, and then it enters into the reactor at the temperature range 523-
723 K. To obtain liquid ketones, the obtained gases are taken to a condensing stage.
Finally, the analysis of the reactor effluent is done using gas-liquid chromatography
(Glinski, 2004)
The general chemical reaction which converts carboxylic acids to ketones is:
Figure 2. Molecular interaction of acetic acid.
4
The aim of this project is to find the kinetic model for the catalytic ketonization
process. Afterwards, experiments were performed to determine the most appropriate
reaction conditions based on the kinetic model. Finally these reaction conditions were
tested. Furthermore, the effect of control variables such as temperature, pressure and
weight hourly space velocity (WHSV) was studied to obtain a global optimum
condition.
5
Figure 3. Diagram of MixAlco Process
6
2. OBJECTIVES
2.1. GENERAL OBJECTIVES
Evaluate ketonization stage of the MixAlco® process on a laboratory scale and
develop the kinetic models and find the global optimal conditions for the process.
2.2. SPECIFIC OBJETIVES
Become familiar with the equipment and protocols used to safely and
effectively run the ketonization process.
Use experimental design to select the best pressure, temperature, WHSV
and catalyst composition.
Determine conversion and selectivity of the reaction using protocols for
gas chromatography with flame ionization detector (GC-FID) analysis.
Calculate the model parameters using data collected on previous tests.
7
3. LITERATURE REVIEW
3.1. Highlights
We must first understand the process for producing mixed secondary alcohols. The fed
biomass enters into a pretreatment stage, and then is carried to fermentation. Here it is
converted to salts of volatile fatty acids (VFAs). Afterwards, the fermented liquor
(contains VFAs) is transferred to amine dewatering and then all the water is extracted.
The concentrated solution of VFAs enters into the recovery stage, where the solution is
evaporated and thermally converted to ketones and calcium carbonate. Finally, the
ketones are transferred to the hydrogenation stage where hydrogen gas, using a suitable
catalyst and alcohol mix, is produced and able to be used as fuel. This process is shown
below.
Figure 4. Schematic diagram of a process for converting biomass to liquid secondary
alcohol fuel (Holtzapple, 1999).
Ketones
Calcium carbonate
Mixed alcohols
Biomass
Hydrogen
gas
VFAs Pretreatment Fermentation
Amine
Dewatering Recovery
Hydrogenation
Lime
Kiln
Undigested
residue
8
On the other hand, if the desired product is a concentrated acid, the process remains the
same as the above, but the resultant acid stream in the amine dewatering stage may be
used directly. Calcium carbonate must be recycled to fermentation to neutralize acid
produced or burnt in the lime kiln which could be used in pretreatment or added into a
fermentor to maintain a higher pH (Holtzapple, 1999).
In this project, we will work in the recovery stage, where the VFAs may be
transformed. The first method mentioned produces ketones, while the other four
methods produce acids. For the purpose of the project we are only interested in the first
method. The methods used in this part are:
Thermal conversion of VFAs to ketones
Displacement of inorganic cation by low-molecular-weight tertiary, then
making a thermal decomposition of the amine carboxylate to release the acids
and regenerate the amines.
Change of the inorganic cation by low-molecular-weight, then high-molecular-
weight tertiary amines, followed by thermal decomposition of the amine
carboxylate.
Displacement of the inorganic cation by ammonia, then high-molecular-weight
tertiary amines, followed by thermal decomposition of the amine carboxylate to
release the acids and regenerate the amines.
9
3.2 Ketonization
Using a thermal conversion to salts from volatile fatty acids a good yield is obtained. In
the metal salts of VFAs, the anion portion is provided by the VFAs, while the cations
are usually alkalines. The most common ones are lithium, sodium, potassium,
magnesium, calcium or barium salts, or a mixture of two or more of these salts. In
figure 5, a schematic representation of this method is shown. The VFAs from an amine
dewatering system should have approximately a 20% concentration of salt and the pH
of the concentrated salt solution should be alkaline. In this process a thermal convertor
is used to avoid undesirable reactions. If the pH value is too high, it should be
decreased by adding carbon dioxide.
Now these VFAs enter a multiple effect evaporator which consists of vapor
disentrainers, heat exchangers and circulating pumps. In the multiple effect evaporator
each vapor disentrainer operates at successively lower pressures, the vapor disentrainer
1 has the highest pressure and the vapor disentrainer 3 has the lowest pressure. The
process steam is fed to heat exchanger 1 which produces vapors to vapor disentrainer 1,
which is fed to heat exchanger 2 and finally to heat exchanger 3. The vapor generated
in the last exchanger could be carried to a previous stage, as the amine dewatering to
provide the latent heat to separate water from amine. The final vapor stream of the
multiple effect evaporator stage is partitioned into two parts, one agitated and the other
quiescent. Liquid from the agitated part is transported through the heat exchanger and is
returned to the agitated part. As vapors are removed, salt precipitates and settles into
10
the quiescent part. It is then pumped through a solids separator and the solid free liquid
is returned to the agitated part of the vapor disentrainer (Holtzapple, 1999).
The salts revealed from separation are carried to the drier. The saturated water vapor
coming out of the drier is propelled by a blower heat exchanger A which superheats the
vapors. It is then returned to the drier for sensible heat provides the latent heat
necessary for water to vaporize from the wet salt. The dry salt stream is transferred to
the thermal convertor. The ketone stream is recovered as product or carried to
hydrogenation. The high stream contains calcium carbonate, but it may contain soluble
minerals that must be purged. The other streams are fed back to any above stage
(Holtzapple, 1999).
11
Figure 5. Schematic diagram of a thermal conversion acid to ketone (Holtzapple,
1999).
Dr. Holtzapple described one embodiment, where a method for thermally converting
volatile fatty acid (VFA) salts to ketones is used. The first part includes the steps of
mixing dry metal of VFAs with a heat transfer agent in a container (evacuated). The
heat agent, containing vapor and metal salt of carbonates, is sufficient to raise the
temperature of metal salts of VFAs to cause a thermal decomposition, which results in
the formation of ketones. Then it is time for separation, where the ketones containing
vapor is separated from the metal carbonate salt and heat transfer agent. The liquid
ketones are recovered by condensing the ketone containing vapor. The container is
12
maintained in a vacuum by condensing the ketones from ketone containing vapor and
removing non condensable gas from the container. The heat transfer agents are hollow
balls that are filled with a substance that melts at the temperature of thermal
decomposition of VFAs; another option is that the heat transfer agent is selected from
steel, glass, or ceramic balls. Preferably the metal carbonate and heat transfer agent are
removed in a container separate from each other, followed by reheating and recycling
of the heat transfer agent back to the container (Holtzapple, 1999).
Conant and Blatt studied a method for producing ketones as fatty acids by passing them
over a catalyst, like MnO or ThO2 at 300° C like Figure 5. According to the following
equation, the pure acetic acid yields only produce acetone, but a mixture of acids will
yield mixed ketones.
For example, if acetic acid and propionic acid were fed, the products would be
acetones, methyl ethyl ketones, and diethyl ketones.
13
Figure 6. Gas phase catalyst ketonization of carboxylic acids.
The above method shows how the ketone is produced from VFAs, and no catalyst is
necessary. It decomposes at temperatures between 300 to 400° C, According to the
following equation:
Acording to Dr. Hurt in The Pyrolysis of Carbon Compounds, this reaction may have a
fairly high yield, as long as the ketone decomposition temperature is not exceeded. One
of the best experimental results for the decomposition of calcium acetate (salt of acetic
14
acid) was obtained by Ardagh et al. (1924). They found a satisfactory decomposition
between 290 to 500 °C, and between 430 to 490 °C. However, he reported that the
reaction actually begins as low as 160 ° C. They calculated the yield for the process
(acetone from calcium acetate) to be 99.5 % of the theoretical yield, during a 7 hour
reaction at 430 °C; after one hour, the yield was 96%. One important conclusion of this
work was to determine two primary factors that contribute to the low yield: the
presence of oxygen in the reaction vessel and the slow removal of the acetone from the
hot vessel, both which directly affect the reaction (Ardagh et al., 1924).
Another advance in the synthesis of ketones from carboxylic acids is the catalytic
ketonization. This process has been carried out through the pyrolytic decomposition of
metal carboxylates, mostly salts of calcium and thorium. Advancement was the direct
ketonization of carboxylic acids in the gas phase over solid catalysts under flowing
condition. Some compounds used in the literature were metal oxides supported on
inorganic carriers like pumice, alumina, silica and titania or active carbon, also, oxides
of thorium, cerium, manganese and zirconium as well as rare earth metals and alkaline
earth metals (Christian, 2009).
Dr. Glinski did important research of the ketonization process. He studied catalytic
mixtures such as propanoic/pentanoic, ethanoic/10-undecanoic and hexanoic/
ocatadecenoic acids. The result was a high yield of ketones irrespective of molecular
weights and molecular ratios of reacting acids. The analytical determinations were
15
done using GC and HPLC techniques; the reaction was selectivity determined directly
from GC measurements and reaction products were identified by GC-MS or by
comparing the retention time with that of an authentic sample. The results shown are in
the Figure 7 and Figure 8 (Glinski, 2004).
Figure 7. Influence of concentration of active phase upon catalytic activity of
CeO2/SiO 2 in ketonization of acetic acid, LHSV = 2 cm 3 g t h ~. Reaction selectivity
>/94%.
16
Figure 8. Catalytic activity of 20 wt.-% CeO2/SiO2 system in ketonization of acetic
acid at various LHSV. Reaction selectivity > 96%.
3.3. Kinetic model
This could be a differential reactor, which has the velocity of reaction constant in all
the points of the reactor. Due to small conversions, small or not very deep reactors, big
reactor-slow reaction and order reaction zero, another option is an integral reactor,
which has the velocity of reaction variable along the reactor due to high conversions.
According to the results reported by Osorio (2010), the obtained maximum conversion
is between 95% and 96% (Osorio, 2010). Therefore our kinetic model will be for an
integral reactor.
The experimental design consists in several trials with a constant initial concentration,
varying the initial flow or the mass of catalyst. According to the following chart:
17
FA0 W/FA0 CA,SAL/CA0 XA
Where:
FA0 = initial flow (mL/min)
W = mass of the catalyst (Kg)
W/FA0 = space time (Kg cat h/ mL)
CA,SAL = Final concentration
CA0 = Initial concentration
XA = this given by the equation:
εA = Variation fractions of the volume for the complete conversion of A. This given by
the equation:
The reaction velocity for any value of X is the slope of this curve shown in Figure 9.
18
Figure 9. Graph conversion - space time.
3.3.1 Adsoption
In order to obtain a kinetic model we have to know which the controlling stage is.
Levenspiel, in his book Chemical Reaction Engineering, describes the process to know
the controlling stage; it is based on the graphic initial velocity - total pressure.
19
If the adsorption is the controlling stage, the graph will be:
Figure 10. Adsorption: controlling stage in the process. Initial velocity –total pressure.
When the adsorption is in the controlling stage the initial velocity is a lineal function of
the pressure.
3.3.2 Desorption
If the desorption is the controlling stage, the graph will be:
Figure 11. Desorption: controlling stage in the process. Initial velocity–total pressure.
20
When the desorption is in the controlling stage, the velocity does not depend on the
total pressure.
3.3.3 Surface reaction
If the surface reaction is the controlling stage, the graph will be:
Figure 12. Surface reactions: controlling stage in the process. Initial velocity –total
pressure.
When the surface reaction is in the controlling stage, the initial velocity increases when
the total pressure increases, until the saturation point, later the speed falls.
21
Gaertner et to the (2009) studied the conversion of ketones from carboxylic acids for
ketonization. Their study to use hexanoic acid, as a representative carboxylic acid, in
presence of 2-butanona like solvent, they worked with controlled conditions of
temperature, pressure mass of the catalyst. Their objective was to study the effects,
partial pressures of the reactants and products, and reaction temperature on the rates of
ketonization (Glinski, 2004).
The reaction is following:
The diagram used for the reaction kinetic studies is shown in the figure 13.
22
Figure 13. Reactor step used for the reaction kinetics experimental studies.
The hexanoic acid is introduced through a HPLC pump into the system, afterwards; the
feed is preheated to achieve the gaseous state. Then, it is sent t to the reactor, where the
catalyst is loaded. The final stream was collected at room temperature in a gas-liquid
separator and drained for gas chromatography analysis (Glinski, 2004). They did that
some graphs that summarize their results.
23
Figure 14. Ketonization reaction rates for varying partial pressures of hexanoic acid
using 2-butanone as solvent at 547 K, 572 K, 597 K and 623 K.
The velocity is shown to several temperatures like function of the partial pressure of the
hexanoic acid (Figure 14). Also the velocity is shown to several pressures as function
of the temperature (Figure 15). The reactor is a total pressure of 1atm.
24
Figure 15. Experimental data and simulation results for ketonization, partial pressure
of hexanoic varied.
The kinetic model was implemented in MATLAB to solve the differential equations.
For the parameters of the model they noticed initial values to be optimized using the
algorithm Levenberg Marquardt (Glinski, 2004).
Where:
25
These reactions involve non linear parameter estimation problems, applying
optimization methods like Levenberg-Marquardt that helps to find a numerical solution
to the problem of minimizing a function. The user should add a vector of observations
or wanted values of the non well-known parameters. It is an iterative procedure
preferably developed with programs like Matlab. The following equation shows their
search.
3.4 Catalyst
There are simple methods for evaluating the physical properties of different catalyst:
3.4.1 Fourier Transform Infrared (FTIR):
It works to determine the chemical composition and show the chemical changes,
polymerization and impurities with known samples. FTIR is based on the interactions
of electromagnetic radiation and molecules. These interactions will be of a different
nature depending on the region of the spectrum in which they are occurring; these
interactions comprise electron excitation, molecular vibrations and molecular rotations.
This technique uses an interferometer, for example the Michelson interferometer, which
consists of two mirrors facing each other at a 90 degree angle. Furthermore, the
interferometer has a ray refractor which is positioned at a 45 degree angle from the
26
mirrors. One of these mirrors is located at a stationary position, while the other one can
move at a constant speed in a direction perpendicular to the frontal plane.
The device that is in charge of splitting the rays allows the mirrors to capture the light
emanating from the source. Fifty percent of the light it absorbs is transmitted while the
rest is reflected. The interferometer also has information about the intensity of all the
frequencies in the light spectra. The information that comes out of the detector is
digitalized and transformed to the Fourier series. Then the signals are converted to the
conventional infrared spectra.
FTIR has different applications:
Characterization and identification of materials.
Polymers and plastics.
Inorganic solids (minerals, catalyst )
Analysis and synthesis of pharmaceutical products.
Analysis of impurities
Tracking of chemical processes
Polymerization.
Catalytic reactions.
Analysis of oils and fuels.
27
3.4.2 Temperature Programmed Desorption (TPD):
It is a technique that allows the determination of the number, the type and the strength
of the active sites present on the surface of the catalyst by measuring the quantity of the
compound that adsorbs at different temperatures. The ammonia present would be the
principal molecule to characterize the acidic centers of the catalyst.
To run the analysis the following equipment was used a temperature control system for
gas stream, a detector of thermal conductivity and valve gases; a temperature control
system for furnace, flowmeter, gas flow and pressure control panel and a calibrated
loop to control the injection of different gases or vapors in the sample
There are three types of molecular probes commonly used for characterizing acid sites
using TPD:
Ammonia
Non-reactive vapors
Reactive vapors
TPD of ammonia is a widely used method for characterization of site densities in solid
acids due to the simplicity of the technique. Ammonia often overestimates the quantity
of acid sites. Its small molecular size allows ammonia to penetrate into all pores of the
solid where larger molecules commonly found in cracking and hydrocracking reactions
only have ess to large micropores and mesopores.
28
Also, ammonia is a very basic molecule which is capable of titrating weak acid sites
which may not contribute to the activity of catalysts. The strongly polar adsorbed
ammonia is also capable of adsorbing additional ammonia from the gas phase.
29
4. METHODOLY
4.1. Research plan
Reactions will be carried in a fixed bed tubular quartz reactor (Figure 16). A constant
metric pump will be used to drive acid into the system; stainless steel tubing will be
used throughout. The acid will pass through coils of tubing inside an oven, which will
be heated to 45 °C; the preheated acid will then pass through a segment of tube
wrapped in heating tape, insulation, and aluminum. This tape will be set to 150 °C
using a variable transformer.
Figure 16. Packed Bed Reactor
The acid vapor will then pass into the reactor where it contacts the zirconia catalyst and
reacts, which will also be wrapped with heating tape covered with insulation, and
30
aluminum; this tape will be set to 400 °C. Both tapes will be monitored. Later, the
reaction products go through a stabilizer where the temperature is around 200 °C.
Product analysis will be done through gas chromatography (GC) connected in line. This
process is similar to oligomerization process shown in Figure 17.
Figure 17. Schematic diagram of the oligomerization process
4.2 Experimental procedure
1. Catalyst is weighed and loaded into the reactor. The catalyst is supported by two
layers of α-alumina.
2. The system is purged for 2 min with N2 at 500 cm3/min.
31
3. The reactor temperature is set. The temperature is controlled by three controllers
(top, medium, and bottom). The objective is to maintain the same temperature along
the catalyst bed. To get the same temperature, the controllers must be set at the
following temperatures:
Top TR – 40 °C
Middle TR – 30 °C
Bottom TR
The system has a Type-K thermocouple that measures the temperature along the
catalyst bed, which allows verification of a constant temperature along the reactor.
The reactor temperature stabilizes after 15 minutes.
4. The liquid reactants are fed to the system with a syringe pump.
5. If hydrogen is added to the acetone reaction, the hydrogen is measured with a mass
flow controller.
6. After the reaction temperature is stabilized (after 10 minutes of feeding), the liquid
products are collected.
7. Then, an on-line analysis of the product stream is performed using a GC connected
to the reactor exit. This GC has two detectors: FID and TCD. The analysis intervals
are 30 minutes, so the samples can be taken every 30 minutes.
8. The liquid sample is collected and analyzed with a GC-MS. This GC-MS analysis
has more detailed compound analysis of the liquid phase.
32
9. Reactions are terminated by cutting off the feed. Then, the reactor is heated to
500°C.
10. Finally, air is fed into the system to regenerate the catalyst (return to Step 1).
The above experimental procedure was taken for Taco & Nieves in their research
Hydrogenation of Ketones and Alcohols Conversion to Hydrocarbons Using HZSM-5
Catalyst.
4.3 Catalyst preparation
For 30 g of catalyst use 12 gr ZrO2, 6 gr TiO2, 6 silica fumed, 6 gr ZrO(NO3)2 · xH2O,
the experimental procedure is shown below.
1. Prepare a solution A of 12 gr of ZrO2 on distilled water. A volumetric flask is used
to make the mixture.
2. Prepare the solution B by mixing 6 gr TiO2, 6 silica fumed and 6 gr ZrO(NO3)2 ·
xH2O.
3. Mix the solution A with the solution B.
4. Add water until a uniform gel is formed.
5. Dry at 120 °C on an oven for approximately 24 hours.
6. Calcinate at 450 °C for approximately 8 hours. A furnace is used to calcinate.
7. Make pellets between 3-5 mm.
33
The above experimental procedure was taken for Osorio in their research catalytic
ketonization of carboxylic acids over zirconium oxide (ZrO2)
4.4 Experimental design The experimentation will be a factorial design combined which has 3 factors:
Each variable have the following ranges:
T1 and T4 (573.15 – 723.15) K
P1 and P4 (14 – 300) psi
F1 and F5 (0.0002 – 0.001) l/min
Temperature
Pressure
Initial Flow
34
5. RESULTS AND ANALYSIS
5.1 Conversion
Table 1. Initial dates
Mass of catalyst W (kg) 0,005
Variation fractions of the volume Ea 0,500
Initial concentration of Acid CA,0 0,729
Table 2. Conversion results at pressure 14.696 psi
Temperature
(°C)
Initial Flow
(mL/min) CA,sal
W/FAO
(Kg cat h/
mL)
CAsal/Ca Xa
300 0.2 0.106 0.0250 0.146 0.829
0.4 0.075 0.0125 0.103 0.840
0.6 0.125 0.0083 0.171 0.847
0.8 0.125 0.0063 0.171 0.853
1 0.123 0.0050 0.168 0.894
350 0.2 0.075 0.0250 0.103 0.839
0.4 0.153 0.0125 0.210 0.848
0.6 0.147 0.0083 0.201 0.851
0.8 0.161 0.0063 0.221 0.875
1 0.160 0.0050 0.219 0.900
400 0.2 0.125 0.0250 0.171 0.846
0.4 0.161 0.0125 0.220 0.855
0.6 0.120 0.0083 0.164 0.875
0.8 0.152 0.0063 0.209 0.913
1 0.149 0.0050 0.204 0.934
450 0.2 0.125 0.0250 0.171 0.865
0.4 0.125 0.0125 0.171 0.877
0.6 0.087 0.0083 0.119 0.900
0.8 0.048 0.0063 0.066 0.925
1 0.154 0.0050 0.211 0.952
35
Table 1 shows the calculations performed based on the data obtained, for a pressure of
14.696 psi, in the first two columns it is shown the temperature and flow conditions that
correspond to it. First, the space-time is estimated given by the ratio of the mass of
catalyst loaded into the reactor in kg to the initial flow in mL / min. If space-time has a
small value, this corresponds to a value greater than the initial flow. The space-time is
symbolized by W/FAO. The value of x -axis on the Figure 1 represents the space-time
measuring, which will be useful to calculate the initial rate of the reaction. The outlet
concentration is measured in the chromatographic analysis for each sample, where the
area under each peak is roughly proportional to the concentration of the species in the
sample.
The initial concentration of acid is the same for all the runs, the solution is made of 450
g of acetic acid and 50 g of water, thus the fraction of acetic acid and water in the
solution are 0.9 and 0.1 respectively. It is necessary to know the moles entering the
system for this, the above data is important to know that you are working with 7.5
moles of acetic acid and 2.7 moles of water. Thus, we estimate the initial concentration
of acetic acid, resulting in 0.729 mole fraction. After calculating the initial
concentration and final, and knowing that the fractional volume change for complete
conversion of acetic acid (εA) is given by the reaction as follows:
36
The results above were used to create a plot, which shows conversion for varying
space-time in order to determine the initial rate of the reaction for any conversion value.
The method consists in determining the slope of the line, this slope is equivalent to
initial rate of the reaction.
Figure 18. Conversion of ketonization reaction for varying t space-time of feed at
different temperature values and a total pressure of 14.696 psi
0,80
0,82
0,84
0,86
0,88
0,90
0,92
0,94
0,96
0,98
1,00
0,0050 0,0150 0,0250
Co
nve
rsio
n (
Xa)
Space time (W/FAO )
T=300 °C
T=350°C
T=400 °C
T=450 °C
37
When the system is at atmospheric pressure, the conversion is higher at slow flows and
high space-time. This could be because the reactants are in a longer contact time with
the catalyst, therefore the reaction will be favored. Thus, it can be concluded that when
the temperature increases the conversion also increases. The isotherms presents the
same behavior, as long as the space-time is increasing the conversion is decreasing.
However, the conversion results are good.
Table 3. Conversion results at pressure 100 psi
Temperature
(°C)
Initial flow
(mL/min) CA,sal
W/FAO
(Kg cat h/
mL)
CAsal/Ca Xa
300 0.2 0.832 0.0250 0.146 0.832
0.4 0.838 0.0125 0.103 0.838
0.6 0.845 0.0083 0.171 0.845
0.8 0.860 0.0063 0.171 0.860
1 0.916 0.0050 0.168 0.916
350 0.2 0.827 0.0250 0.103 0.827
0.4 0.830 0.0125 0.210 0.830
0.6 0.841 0.0083 0.201 0.841
0.8 0.843 0.0063 0.221 0.843
1 0.862 0.0050 0.219 0.862
400 0.2 0.847 0.0250 0.171 0.847
0.4 0.853 0.0125 0.220 0.853
0.6 0.853 0.0083 0.164 0.853
0.8 0.854 0.0063 0.209 0.854
1 0.868 0.0050 0.204 0.868
450 0.2 0.880 0.0250 0.171 0.879
0.4 0.883 0.0125 0.171 0.883
0.6 0.892 0.0083 0.119 0.892
0.8 0.905 0.0063 0.066 0.905
1 0.905 0.0050 0.211 0.905
38
Figure 19. Conversion of ketonization reaction for varying t space-time of feed at
different temperature values and a total pressure of 100 psi
The figure 19 shows how the tendency curves remain constant. To enhance the
reaction, the temperature and space-time should increases. The space-time depends of
the catalyst mass and the initial flow; there are two ways to increase its value: it can be
increasing the catalyst mass or decreasing the initial flow. In order to analyze the
economic part of the process, the best option would be decreases the initial flow, thus
the raw materials such as acetic acid would be less used and the measured conversion
will not be affected. The problem in this part would be the time; if the initial flow is too
0,80
0,82
0,84
0,86
0,88
0,90
0,92
0,94
0,96
0,98
1,00
0,005 0,01 0,015 0,02 0,025
Co
nve
rsio
n (
Xa)
Space time (W/FAO)
T=300 °C
T=350°C
T=400 °C
T=450 °C
39
slow, the reaction takes more time than usual and the quantity produced ketones would
not be the same compared to the ones with higher flows. If the amount of the catalyst is
increased the flows could be faster, in this way, the reaction will be optimized but the
catalyst costs will be increased. A cost-benefit analysis shout be implemented and then
infer the most appropriate and effective way to increase the space-time.
If we compare the values of conversion at the same temperature and initial flow rate,
the conversion does not have a significant change when pressure is increased from
14.696 psi to 100 psi. Conversion reduces only when it is combined with lower
temperatures. Temperature is lower due to the lack of energy to achieve the best results
from the reaction as the pressure increases. We know that the equilibrium of high
pressure is not as efficient as in lower pressures, because the reaction goes from two
moles to three, meaning that the ideal conditions to produce fewer moles are high
pressures. Taken this case in consideration, we want to produce more moles; therefore
low pressures make the reaction more efficient.
40
Table 4. Conversion results at pressure 200 psi
Temperature
(°C)
IInitial flow
(mL/min) CA,sal
W/FAO
(Kg cat h/
mL)
CAsal/Ca Xa
300 0.2 0.830 0.0250 0.146 0.829
0.4 0.834 0.0125 0.103 0.834
0.6 0.841 0.0083 0.171 0.841
0.8 0.844 0.0063 0.172 0.844
1 0.863 0.0050 0.168 0.863
350 0.2 0.839 0.0250 0.103 0.839
0.4 0.845 0.0125 0.210 0.845
0.6 0.849 0.0083 0.201 0.849
0.8 0.855 0.0063 0.220 0.856
1 0.864 0.0050 0.219 0.864
400 0.2 0.841 0.0250 0.171 0.841
0.4 0.843 0.0125 0.220 0.843
0.6 0.852 0.0083 0.164 0.852
0.8 0.853 0.0063 0.208 0.853
1 0.858 0.0050 0.204 0.858
450 0.2 0.859 0.0250 0.171 0.859
0.4 0.866 0.0125 0.172 0.866
0.6 0.872 0.0083 0.119 0.872
0.8 0.880 0.0063 0.066 0.879
1 0.903 0.0050 0.211 0.902
41
Figure 20. Conversion of ketonization reaction for varying t space-time of feed at
different temperature values and a total pressure of 200 psi
0,80
0,82
0,84
0,86
0,88
0,90
0,92
0,94
0,96
0,98
1,00
0,005 0,01 0,015 0,02 0,025
Co
nve
rsio
n (
Xa)
Space time (W/FAO)
T=300 °C
T=350°C
T=400 °C
T=450 °C
42
Figure 21. Conversion of ketonization reaction for varying t space-time of feed at
different temperature values and a total pressure of 300 psi
0,80
0,82
0,84
0,86
0,88
0,90
0,92
0,94
0,96
0,98
1,00
0,005 0,01 0,015 0,02 0,025
Co
nve
rsio
n (
Xa)
Space time (W/FAO)
T=300 °C
T=350°C
T=400 °C
T=450 °C
43
Table 5 Conversion results at pressure 300 psi
Temperature
(°C)
I Initial Flow
(mL/min) CA,sal
W/FAO
(Kg cat h/
mL)
CAsal/Ca Xa
300 0.2 0.844 0.0250 0.148 0.844
0.4 0.847 0.0125 0.103 0.847
0.6 0.858 0.0083 0.171 0.857
0.8 0.861 0.0063 0.171 0.860
1 0.861 0.0050 0.168 0.861
350 0.2 0.826 0.0250 0.103 0.826
0.4 0.838 0.0125 0.210 0.838
0.6 0.842 0.0083 0.201 0.842
0.8 0.845 0.0063 0.220 0.845
1 0.850 0.0050 0.219 0.850
400 0.2 0.845 0.0250 0.171 0.845
0.4 0.851 0.0125 0.220 0.851
0.6 0.855 0.0083 0.164 0.855
0.8 0.860 0.0063 0.208 0.860
1 0.880 0.0050 0.204 0.879
450 0.2 0.862 0.0250 0.171 0.862
0.4 0.867 0.0125 0.172 0.867
0.6 0.879 0.0083 0.119 0.879
0.8 0.880 0.0063 0.066 0.879
1 0.881 0.0050 0.211 0.881
5.2 Selectivity
The selectivity can be written as follows:
Where:
ND = moles of desired product
U = moles of undesired product
44
Figure 22. Concentration of ketones on the product for varying temperature at low -
WHSV
The Figure 22 shows how the selectivity decreases when the temperature increases.
One of the most concentrated side components were aromatic hydrocarbons such as
1,3,5 trimethylbenzene. Mattox et to the (1960) studied the conversion of aromatics
from ketones in the presence of a alumino-silicate catalyst [xx], the results show a
highly effective process when the operating conditions are at temperature 204°C to
about 537°C and a total pressure of 1000 psig. These temperature and pressure
conditions are similar of ketonization conditions, the fact that the selectivity decreases
0,4
0,5
0,6
0,7
0,8
0,9
1
300 350 400 450
Sele
ctiv
ity
(%)
Temperature (°C)
14 atm
100 atm
200 atm
300 atm
45
in high pressure support the production of aromatic, finally, the metal catalyst,
zirconium oxide, is supported over silica and alumina as in the Mattox’s studies.
Figure 23. Concentration of ketones on the product for varying temperature at high -
WHSV
5.3 Kinetic model
The initial rate of reaction is the slope in the initial point. Each point represents an
initial rate for a total pressure in the reactor. In order to determine the controlling stage,
it is necessary to check the tendency graph (initial rate - total pressure), and finally
clarify if it is adsorption, desorption or surface reaction.
0,4
0,5
0,6
0,7
0,8
0,9
1,0
300 350 400 450
Sele
ctiv
ity
(%)
Temperature (°C)
14 atm
200 atm
300 atm
100 atm
46
Figure 24. Controlling stage
As shown in Figure 24, the initial velocity is not a linear function of the pressure but it
does depend on the total pressure. Therefore the controlling stages are neither
adsorption nor desorption. The result shows the initial velocity as a function of
pressure. For this reason the surface reaction is the controlling stage where the initial
velocity decreases when the total pressure increases and the initial velocity increases
when the temperature increases.
160
165
170
175
180
185
190
195
14 114 214
Init
ial
rate
Pressure total (psi)
T=300°C
T=350°C
T=400°C
T=450°C
47
The rate expression for the ketonization can be written as:
Where:
krs = ketonization rate constant
KA = rate constant for the adsorption
KRS = rate constant for the surface reaction
KD, CO2 = rate constant for the desorption of CO2
KD,H2O = rate constant for the desorption of H2O
PCH3COOH= acetic acid vapor pressure
PCH3COCH3= acetone vapor pressure
PCO2 = carbon dioxide vapor pressure
PH2O = wáter vapor pressure
5.3.1 Initial parameter estimation
Ki, j is the equilibrium constants for species j.
48
In the initial parameter estimation, the equilibrium constants for species and the
forward rate constant for ketonization reaction will be used. These are given as
thermodynamic functions. (Christian, 2009).
(17)
Where:
Ki,eq= equilibrium constant
-∆H°i =enthalpy of formation
∆S°i = entropy of formation
R= gas constant
T= temperature
For each one of the species it was necessary to know the values of the constants that
allowed for the calculation of the values of enthalpy and entropy used inside of the
model. The data is shown in Table 6.
Table 6. Constants for the calculation of enthalpy (C.L, 2003)
Where: (18)
For the calculation of the formation entropy, Equation 18 was used, where the previous
calculated entropy is related to the value of the Gibbs free energy, calculated in the
same way as the enthalpy but with different constants (Table 7).
Component A B C ∆Hi
Acetic Acid C2H4O2 -422.548 -0.048354 0.000023337 -445.3112
Acetone C3H6O -199.175 -0.071484 0.000032534 -233.8551
Carbon Dioxide CO2 -393.422 0.00015913 -1.3945E-06 -394.0362
Water H2O 33.933 -0.0084186 0.000029906 43.4843
49
Table 7. Constants for the calculation of the Gibbs free energy (C.L, 2003)
Component A B C ∆Gi
Acetic Acid C2H4O2 -425.963 1.93E-01 0.000016362 -277.506
Acetone C3H6O -218.777 2.12E-01 0.000026619 -51.715
Carbon Dioxide CO2 -393.422 -0.0038212 1.3322E-06 -395.489
Water H2O -255.422 -0.02486 0.00008456 -228.600
(19)
With these two terms and the optimal operating conditions, the value for each one of
equilibrium constants for species was obtained. The final values of entropy are shown
in Table 8.
Table 8. Entropy calculated
Furthermore, it was necessary to calculate the forward rate constant for ketonization
reaction, described by the following equation.
(20)
Where:
ki,= Arrhenius rate constant
Ai = pre-exponential factor
Eai = activation energy
Component ∆Si
Acetic Acid C2H4O2 -0.232048
Acetone C3H6O -0.251870
Carbon Dioxide CO2 0.002009
Water H2O 0.376249
50
R= gas constant
T= temperature
For this equation, the Ai and Eai terms were found graphically, that is to say, Figure 25
represents the Arrhenius graphic where the slope is equivalent to the activation energy
and the intercept to the pre-exponential value.
Figure 25. Arrhenius Graphic (Christian, 2009).
The optimization process began with the calculated values based on the thermodynamic
functions, shown in Table 4. This result will be optimized in an iterative process
developed in Matlab. The equation involves non-linear, parameter estimation problems.
It is necessary to apply optimization methods like Levenberg-Marquardt that help to
find a numerical solution.
y = -3822,x + 10,42
R² = 0,982
2
2,5
3
3,5
4
4,5
5
5,5
0,0013 0,0015 0,0017 0,0019
ln r
ate
( m
ol
min
-1k
g C
at-1
)
Temperature (K-1)
51
Table 9. Initial parameters
KC2H4O2 0.97
KC3H6O 0.97
KCO2 1.00
KH2O 1.04
Finally, the program in Matlab accomplished an iterative process where the values of
the constants were optimized and the final kinitic model was obtained.
Table 10. Final parameters for the kinetic model.
Ea 7,44 ± 4,99
A 2,33 ± 1,56
KC3H4O2 0,02 ± 0,07
KC3H6O 5,18 ± 3,46
KCO2 37,6 ± 8,24
KH2O 110 ± 11,6
52
Figure 26. Comparison of experimental results with theoretical calculations obtained
from kinetic model.
0,82
0,84
0,86
0,88
0,9
0,92
0,94
0,96
0,98
1
1,02
0,0063 0,0113 0,0163 0,0213
Co
nve
rsio
n (
Xa)
Space time (W/FAO )
Therorical convertion
Experimental convertion
53
6. CONCLUSIONS
The ketonization reaction was carried out over a catalyst of zirconium oxide supported
on silica, alumina and titanium oxides. According to the analysis of the conversion
results, the most appropriated conditions for the ketones production are slow initial
flows, low pressures and high temperatures. The recommended conditions were 450 °C,
14.6 psi and a flow rate between 0.2 y 0.6 mL/min. Residence time is higher when the
experimental flow is slow; this can be explained because the interaction between
catalyst and reactants is favored producing more ketones. For any reaction, when the
number of moles increases, such as in the case of ketonization low pressures are
recommended, the experimental results confirm this hypothesis because when the
pressures are high the conversion is significantly low.
In regards to the selectivity, the results vary depending on the experimental conditions,
for example, when the temperatures and pressures are high; the GC-MS shows presence
of aromatic hydrocarbons.
The initial velocity for each experiment is a function of the pressure; hence the surface
reaction between the adsorbed species is the controlling stage of the process. Based on
this result the rate expression for the ketonization was found. It is suggested to expand
the experimental range in order to have greater certainty of the controlling step.
54
Although in Figure 24 the initial rate is a function of total pressure, the behavior of the
graph could present significant changes in other conditions.
For the estimation of the initial parameters, thermodynamic functions based on the
characteristics of each compound give a good initial approximation of the parameters
that are being looked for. The optimized parameters give a fairly accurate solution to
the kinetic model which is reflected in the closeness between the experimental and
theoretical values.
55
REFERENCES
Ardagh, E. G. R., Bbarbour, A. D., McClellan, G. E & McBride, E. W., 1924,
Distillation of Acetate of Lime., Industrial and Engineering Chemistry, 16
(11) 1133-1139.
Conant, J.B. & Blatt A.H., 1947, The Chemistry of Organic Compounds, Macmillan
Co., New York.
D.B.Ingram, Ketonization of acetic acid, 2002, Department of Chemical Engineering,
Texas A&M University.
Gaertner,C, 2008, Catalytic coupling of carboxylic acids by ketonization as a
processing step in biomass conversion, Journal of Catalysis, Vol. 266, pp.71-
78.
Glinski, M., 2004, Catalytic ketonization of carboxylic acids synthesis of saturated and.
reaction kinetics and catalysis letters, vol 69, pp. 123-128.
Holtzapple, M. T, 1999, Thermal conversion of volatile fatty acid salts to ketones.
United States Patent Office. Patent No. WO/1999/000348. Texas A & M
university, College Station, Texas, US.
Johnson V, Champan J, Chen L, Kimmich B, & Zink J, 2009, Ethanol production from
acetic acid utilizing a cobalt catalyst. United States Patent Office. Patent No.
7.608.744.
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Kang S, Sung S & Sang K, 2008. Reaction kinetics of reduction and oxidation of metal
oxides for hydrogen production. Daejeon, South Korea.
Kawano, T, 2005. Water vapor decomposition reaction on ZrNi alloy. Japan.
Kunihiko M, Ichihara-shi, & Tatsuo S, 2011, Alcohol production process and acid-
treated raney cataly. United States Patent Office, patent No
2011/0015450A1.
Martinez, M.C. Huff and M.A. Barteau, 2003, Ketonization of acetic acid on titania
functionalized silica monoliths. Journal of Catalysis Vol. 222, pp. 404-409.
Nieves, E & Holtzapple M, 2010, Hydrogenation of Ketones and Alcohols Conversion
to Hydrocarbons Using HZSM-5 Catalyst. ARTIE McFERRIN Department
of Chemical Engineering, Texas A&M University, College Station, Texas,
US.
Osorio, C. 2010, Catalytic Ketonization of carboxylic acids over zirconium oxide
(ZrO2). Texas A&M University, College Station, Texas, US.
Taco, S 2009, Alcohols and Ketones Conversion to Hydrocarbons Using HZSM-5,
Department of Chemical Engineering, Texas A&M University.
57
Jackson D, 2006. Processes occurring during deactivation and regeneration of metal
and metal oxide catalysts. Scotland,UK.
Yang YC, Weng H, 2010, Regeneration of Coked Al-Promoted Sulfated Zirconia
Catalysts by High Pressure Hydrogen. Taiwan.
58
APPENDIX A
Experimental Procedure
Catalyst is weighed and loaded into the reactor. The catalyst is supported by two
layers of α-alumina.
The system is purged for 2 min with N2 at 500 cm3/min.
The reactor temperature is set. The temperature is controlled by three controllers
(top, medium, and bottom). The objective is to maintain the same temperature
along the catalyst bed. To get the same temperature, the controllers must be set
at the following temperatures:
o Top TR – 40 °C
o Middle TR – 30 °C
o Bottom TR
The system has a Type-K thermocouple that measures the temperature along the
catalyst bed, which allows verification of a constant temperature along the
reactor. The reactor temperature stabilizes after 15 minutes.
The liquid reactants are fed to the system with a syringe pump.
If hydrogen is added to the acetone reaction, the hydrogen is measured with a
mass flow controller.
After the reaction temperature is stabilized (after 10 minutes of feeding), the
liquid products are collected.
59
Then, an on-line analysis of the product stream is performed using a GC
connected to the reactor exit. This GC has two detectors: FID and TCD. The
analysis intervals are 30 minutes, so the samples can be taken every 30 minutes.
The liquid sample is collected and analyzed with a GC-MS. This GC-MS
analysis has more detailed compound analysis of the liquid phase.
Reactions are terminated by cutting off the feed. Then, the reactor is heated to
500°C.
Finally, air is fed into the system to regenerate the catalyst (return to Step 1).
The above experimental procedure was taken for Taco & Nieves in their research
Hydrogenation of Ketones and Alcohols Conversion to Hydrocarbons Using HZSM-5
Catalyst.
Catalyst preparation
For 30 g of catalyst use 12 gr ZrO2, 6 gr TiO2, 6 silica fumed, 6 gr ZrO(NO3)2
· xH2O, the experimental procedure is shown below.
Prepare a solution A of 12 gr of ZrO2 on distilled water. A volumetric flask is
used to make the mixture.
Prepare the solution B by mixing 6 gr TiO2, 6 silica fumed and 6 gr ZrO(NO3)2
· xH2O.
Mix the solution A with the solution B.
Add water until a uniform gel is formed.
60
Dry at 120 °C on an oven for approximately 24 hours.
Calcinate at 450 °C for approximately 8 hours. A furnace is used to calcinate.
Make pellets between 3-5 mm.
The above experimental procedure was taken for Osorio in their research
catalytic ketonization of carboxylic acids over zirconium oxide (ZrO2)
61
APPENDIX B
Calculations
Adsorption
Surface reaction
Desorption
Where
62
When the adsorption is the controlling stage:
63
When the surface reaction is the controlling stage:
64
APPENDIX C
GC-MS results
T=573 K, P=14 atm, F=0.2 ml/min
Pk# RT Area% Library/ID
Molar
fraction
1 0.86 6.36 2-Propanone 8.91164
2 0.94 21.67 No matches found 19.36962
3 1.89 7 2-Pentanol 6.25692
4 2.42 0.43 2-Hexanone 0.38435
5 2.69 53.93 Acetic acid 10.62442
6 2.8 2.12 3-Hexanol 3.11952
7 4.79 7.11 2-Heptanone 6.35524
8 5.63 4.96 Hydrazine, ethyl-, ethanedioate (1: 4.43347
9 6.01 0.12 cis-3a-Methyl-2,3,4a,6,7,7a-hexahyd 0.10726
10 6.79 0.35 Benzene, 1,3,5-trimethyl- 0.31285
11 7.07 0.18 2-Octanone 10.93173
12 7.91 1.09 3-Octanol 2.61003
13 9.35 0.63 4-Nonanone 4.19213
14 10.23 10.17 Hexanoic acid 9.09041
15 11.13 0.24 5-Undecanone, 2-methyl- 0.21452
16 11.6 12.55 Heptanoic acid 12.22780
17 12.68 0.29 5-Decanone 0.25922
18 13.04 0.29 Cyclohexane, (1-methylethyl)- 0.25922
19 14.04 0.22 6-Dodecanone 0.19665
20 15.32 0.16 7-Tridecanone 0.14302
100
T=623 K, P=14 atm, F=0.2 ml/min
Pk# RT Area% Library/ID Molar fraction
1 0.8 3.61 Carbon dioxide 3.33864
2 0.94 11.93 2-Propanone 11.0332
3 2.11 0.34 2-Pentanol 0.31444
4 2.34 0.14 3-Hexanone 1.13754
5 2.45 36.88 Acetic acid 7.51702
7 3.83 8.28 Propanoic acid 7.65759
8 5.23 9.21 2-Heptanone 8.51768
9 7.08 14.81 Butanoic acid 13.6967
10 7.69 2.12 2-Octanone 8.18474
12 8.15 0.11 3-Octanol 0.10173
13 8.81 4.28 Butanoic acid 3.95827
65
14 9.37 0.1 4-Nonanone 1.31326
17 10.89 15.87 Hexanoic acid 14.677
18 11.25 1.03 4-Decanone 0.95257
19 12.27 16.05 Heptanoic acid 14.8435
20 12.8 1.57 6-Dodecanone 1.45198
21 14.16 0.72 5-Undecanone, 2-methyl- 0.66588
22 15.4 0.52 7-Tridecanone 0.63813
100
T=673 K, P=14 atm, F=0.2 ml/min
Pk# RT Area% Library/ID
Molar
fraction
1 0.32 1.78 2-Propanone 11.37233
2 0.82 7.82 1-Propene, 2-methyl- 6.846162
3 0.87 64.63 Acetic acid 12.47068
4 1.06 0.98 2-Butanone 0.857959
5 2.37 0.36 No matches found 0.315169
6 2.46 0.43 2-Hexanone 0.376451
7 3.39 0.11 2-Hexanol 0.096302
8 4.13 0.17 1-Octene, 2-methyl- 0.14883
9 4.79 9.33 2-Heptanone 10.40932
11 5.71 2.06 1,2,3,3-TETRAMETHYL-4-METHYLENE-CYC 1.803465
12 6.02 0.93 Isoterpinolene 0.814185
13 6.82 1.46 Benzene, 1,3,5-trimethyl- 1.278184
14 7.25 0.32 2-Octanone 20.66981
16 9.88 7.79 2-Nonanone 6.819898
17 10.36 11.82 Butanoic acid 10.34803
18 11.17 0.18 4-Decanone 0.157584
19 11.85 14.97 Heptanoic acid 13.10576
20 12.6 1.83 Octanoic acid 1.602107
21 12.72 0.25 5-Undecanone, 2-methyl- 0.218867
22 14.07 0.2 6-Dodecanone 0.175094
23 15.33 0.13 7-Tridecanone 0.113811
100
T=723 K, P=14 atm, F=0.2 ml/min
Pk# RT Area% Library/ID
Molar
fraction
1 0.32 1.78 2-Propanone 11.37233
2 0.82 7.82 1-Propene, 2-methyl- 6.846162
3 0.87 64.63 Acetic acid 12.47068
66
4 1.06 0.98 2-Butanone 0.857959
5 2.37 0.36 No matches found 0.315169
6 2.46 0.43 2-Hexanone 0.376451
7 3.39 0.11 2-Hexanol 0.096302
8 4.13 0.17 1-Octene, 2-methyl- 0.14883
9 4.79 9.33 2-Heptanone 10.40932
11 5.71 2.06 1,2,3,3-tetramethyl-4-methylene-cyc 1.803465
12 6.02 0.93 Isoterpinolene 0.814185
13 6.82 1.46 Benzene, 1,3,5-trimethyl- 1.278184
14 7.25 0.32 2-Octanone 20.66981
16 9.88 7.79 2-Nonanone 6.819898
17 10.36 11.82 Butanoic acid 10.34803
18 11.17 0.18 4-Decanone 0.157584
19 11.85 14.97 Heptanoic acid 13.10576
20 12.6 1.83 Octanoic acid 1.602107
21 12.72 0.25 5-Undecanone, 2-methyl- 0.218867
22 14.07 0.2 6-Dodecanone 0.175094
23 15.33 0.13 7-Tridecanone 0.113811
100
T=523 K, P=14 atm, F=0.4 ml/min
Pk# RT Area% Library/ID Molar
fraction
1 0.94 47.6 2-Propanone 41.1815
2 1.94 11.23 2-Pentanol 9.71573
3 2.77 3.33 3-Hexanol 5.84847
4 2.87 70.67 Acetic acid 13.4755
5 4.85 2.17 4-Heptanol 15.4085
6 7.66 1.84 4-Octanol 5.82251
7 9.31 1.58 Hexanoic acid 1.36695
8 9.76 4.66 4-Octanol, 7-methyl- 4.03164
9 9.95 0.9 2-Nonanol 0.77864
10 10.82 1.06 Heptanoic acid 0.91707
11 11.43 0.92 5-Decanol 0.79595
12 12.91 0.76 6-Undecanol 0.65752
100
T=623 K, P=14 atm, F=0.4 ml/min
Pk# RT Area% Library/ID Molar
fraction
1 0.85 70.79 2-Propanone 59.94825
67
2 1.8 4.14 2-Hexanol 3.505944
3 3.73 8.73 2-Heptanol 7.392969
4 4.25 82.01 Acetic acid 15.3069
5 5.82 6.38 Benzene, 1,3,5-trimethyl- 5.40288
6 9.37 2.1 4-Nonanol 1.778377
7 9.8 1.82 Benzene, 1,2,3,4-tetramethyl- 1.54126
8 10.55 6.05 Hexanoic acid 5.12342
100
T=673 K, P=14 atm, F=0.4 ml/min
Pk# RT Area% Library/ID Molar
fraction
1 0.88 97.49 2-Propanone 81.8207
2 2.95 86.89 Acetic acid 16.0727
3 4.43 2.51 2-Heptanol 2.10658
100
T=723 K, P=14 atm, F=0.2 ml/min
Pk# RT Area% Library/ID
Molar
fraction
1 0.7 16.1 2-Propanone 21.7015
2 2.52 22.78 3-Hexen-2-one 19.9339
3 3.66 0.73 Benzene, 1,3-dimethyl- 0.63879
4 4.9 3.57 1,3-Cyclohexadiene, 1,5,5,6-tetrame 3.12397
5 5.65 0.9 1,4-Cyclohexadiene, 3,3,6,6-tetrame 0.78755
6 5.96 2.76 ,alpha,-Terpinene 2.4151
7 6.55 0.92 Benzene, 1,3,5-trimethyl- 30.8109
8 6.92 64.78 Acetic acid 12.4938
9 7.47 0.41 1,3-Cyclohexadiene, 1,2,6,6-tetrame 0.35877
10 8.06 0.36 Benzene, 1,2,3-trimethyl- 0.31502
11 10.01 0.66 Benzene, 1,2,3,5-tetramethyl- 0.5775
12 10.11 1.94 Benzene, 1,2,3,4-tetramethyl- 1.6976
13 10.25 5.32 2-Cyclohexen-1-one, 3,5,5-trimethyl 4.6553
14 12.61 0.56 Benzene, 4-(2-butenyl)-1,2-dimethyl 0.4900
100
T=573 K, P=14 atm, F=0.6 ml/min
Pk# RT Area% Library/ID Molar
fraction
2 0.95 28.76 2-Propanone 36.16619
3 1.47 26.86 Acetic acid 5.590179
68
4 1.92 8.21 2-Pentanol 10.32106
13 9.79 4.93 1,2-Heptanediol 6.203966
12 7.99 2.98 2-Octanol 3.74882
8 2.86 2.69 2-Hexanol 3.380548
18 12.94 2.66 1,2-Heptanediol 3.342776
11 7.83 2.27 3-Octanol 2.86119
16 11.45 2.17 5-Decanol 2.72899
7 2.75 2.12 2-Butanol 2.66289
15 9.99 2.05 2-Nonanol 2.587347
10 7.64 1.47 4-Octanol 1.84136
9 4.81 1.36 4-Heptanol 1.699717
14 9.88 0.62 3-Nonanol 0.774315
19 14.27 0.5 6-Dodecanol 0.623229
5 2.09 0.49 Benzene, methyl- 0.613787
17 11.54 0.42 3-Heptanol 0.528801
6 2.67 0.35 2-Butanol, 2-methyl- 0.434372
100
T=623 K, P=14 atm, F=0.6 ml/min
Pk# RT Area% Library/ID Molar
fraction
1 0.84 87.23 2-Propanone 74.43941
2 1.15 77.96 Acetic Acid 14.66306
3 1.35 4.49 2-Hexanol 3.831629
4 2.52 8.28 2-Heptanol 7.065899
100
T=673 K, P=14 atm, F=0.6 ml/min
Pk# RT Area% Library/ID Molar
fraction
1 0.78 2.31 Carbon dioxide 2.0335
2 0.81 0.33 2-Propanone 27.2015
3 0.9 61.6 Acetic acid 11.9517
4 1.07 17.25 2-Butanol 15.1853
5 2.15 12.27 2-Pentanol 10.8014
6 2.36 0.19 Octane 0.1673
7 2.49 0.27 2-Hexanol 6.6903
8 3.54 0.23 Benzene, ethyl- 0.2025
9 3.74 0.24 Undecane, 5,6-dimethyl- 0.2113
10 4.54 0.2 Nonane 0.1761
11 4.85 0.49 4-Heptanol 2.8962
69
12 5.23 0.42 2-Propanol, 1-ethoxy- 0.3697
13 5.74 14.61 2-Heptanol 12.8613
14 7.74 1.49 4-Octanol 4.6744
15 9.35 0.33 4-Nonanone 0.2905
16 9.81 3.29 4-Nonanol 3.4332
17 11.43 0.56 5-Decanol 0.4930
18 12.91 0.41 2,3-Octanediol 0.3609
100
T=723 K, P=14 atm, F=0.6 ml/min
Pk# RT Area% Library/ID Molar
fraction
1 0.77 13.21 Carbon dioxide 12.06486
2 0.84 29.35 2-Propanone 26.80573
3 1.03 19.76 2-Pentanol 18.04706
4 1.13 7.99 5-Hexen-2-one 7.297368
5 1.34 13.46 2-Pentene, 4,4-dimethyl-, (E)- 12.29319
6 2.31 2.2 3-Hexanol, 2-methyl- 2.009288
7 2.64 10.36 2-Heptanol 9.461919
8 4.36 43.11 Acetic acid 8.677871
9 6.17 1.09 3-Octanol 1.844891
10 8.94 1.64 1,2-Heptanediol 1.497833
100
T=623 K, P=14 atm, F=0.8 ml/min
Pk# RT Area% Library/ID Molar
fraction
1 0.83 10.7 Carbon dioxide 8.980643
2 0.9 85.92 2-Propanone 72.11372
3 3.09 0.57 3-Hexen-2-one 0.478408
4 3.92 0.24 2-Pentanone, 4-hydroxy-4-methyl- 0.201435
5 4.27 86.91 Acetic acid 16.07715
6 5.51 0.47 2-Heptanol 0.394477
7 6.73 1.48 Benzene, 1,2,3-trimethyl- 1.242182
8 10.23 0.61 2-Cyclohexen-1-one, 3,5,5-trimethyl 0.511981
100
T=673 K, P=14 atm, F=0.8 ml/min
Pk# RT Area% Library/ID Molar
fraction
1 0.81 16.77 2-Propanone 66.4391
70
2 0.86 81.34 Acetic acid 15.2021
3 2.23 9.35 3-Hexen-2-one 7.9286
4 2.62 1.02 3-Penten-2-one, 4-methyl- 0.8649
5 3.38 1.42 2-Pentanone, 4-hydroxy-4-methyl- 1.2041
6 4.3 0.89 1,3-Cyclohexadiene, 1,2,6,6-tetrame 0.7547
7 5.09 0.45 1,4-Cyclohexadiene, 3,3,6,6-tetrame 0.3816
8 5.46 1.72 cis-3a-Methyl-2,3,4a,6,7,7a-hexahyd 1.4585
9 6.4 5.04 Benzene, 1,2,3-trimethyl- 4.2738
10 10.16 1.76 2-Cyclohexen-1-one, 3,5,5-trimethyl 1.4924
100
T=723 K, P=14 atm, F=0.8 ml/min
Pk# RT Area% Library/ID Molar
fraction
1 0.86 5.06 2-Propanone 9.0159
2 0.97 8.57 2-Propanol 8.1590
3 1.14 19.53 2-Butanol 18.5934
4 1.62 4.4 2-Butanol, 3-methyl- 4.1890
5 2.47 0.75 3-Penten-2-one, 4-methyl- 0.7140
6 2.55 1.34 3-Hexanol 4.5317
7 2.7 22.9 Acetic acid 4.8052
8 3.52 0.17 Benzene, ethyl- 0.1618
9 3.7 0.42 2-Pentanone, 4-hydroxy-4-methyl- 0.3999
10 5.52 26.05 2-Heptanol 24.8007
11 7.72 1.74 4-Octanol 8.9302
12 7.94 1.52 3-Heptanol, 5-methyl- 1.4471
13 9.29 0.3 Cyclopentanol, 1-methyl- 0.2856
14 9.89 9.58 4-Nonanol 12.5670
15 11.45 1.29 6-Dodecanol 1.2281
16 11.54 0.18 3-Decanol 0.1714
100
T=573 K, P=14 atm, F=1.0 ml/min
Pk# RT Area% Library/ID Molar
fraction
1 0.88 98.54 2-Propanone 86.4600
2 1.36 87.04 Acetic acid 12.2589
3 2.09 0.75 3-Hexen-2-one 0.6580
4 9.88 0.71 n-Octyl acetate 0.6229
100
71
T=623 K, P=14 atm, F=1.0 ml/min
Pk# RT Area% Library/ID Molar
fraction
1 0.89 98.66 2-Propanone 82.92078
2 1.99 86.12 Acetic acid 15.9530
3 2.31 1.34 3-Hexen-2-one 1.12623
100
T=673 K, P=14 atm, F=1.0 ml/min
Pk# RT Area% Library/ID Molar
fraction
1 0.8 19.21 Carbon dioxide 16.3557
2 0.85 80.79 2-Propanone 68.78588
3 1.23 79.18 Acetic acid 14.85843
100
T=723 K, P=14 atm, F=1.0 ml/min
Pk# RT Area% Library/ID Molar
fraction
1 0.9 88.72 2-Propanone 75.06711
2 1.68 82.52 Acetic acid 15.38874
3 2.13 10.06 3-Hexen-2-one 8.511893
4 3.2 1.22 2-Pentanone, 4-hydroxy-4-methyl- 1.032257
100
T=573 K, P=100 atm, F=0.2 ml/min
Pk# RT Area% Library/ID Molar
Fraction
1 0,82 81,11 2,Propanone 67,4842
2 1,21 18,89 2-Hexanol 16,7991
3 1,64 91,61 Acetic acid 15,7166
100
T=673 K, P=100 atm, F=0.2 ml/min
Pk# RT Area% Library/ID Molar
fraction
1 0,89 67,2 2-Propanone 57,31624
2 1,85 13,74 3-Hexen-2-one 11,71912
72
3 2,6 1,33 2-Pentanone, 4-hydroxy-4-methyl- 1,134384
4 6,14 17,73 Benzene, 1,2,4-trimethyl- 15,12228
78,24 Acetic acid 14,70798
100
T=723 K, P=100 atm, F=0.2 ml/min
Pk# RT Area% Library/ID Molar
Fraction
1 0,81 12,12 Carbon dioxide 9,710
2 0,86 32,88 2-Propanone 26,343
3 1,5 2,19 2-Pentanone, 4-methyl- 1,755
4 1,57 2,15 5-Hexen-2-one 11,081
5 1,83 0,29 2-Hexanone, 5-methyl- 9,358
6 2,07 11,68 Acetic acid 10,763
7 2,97 0,73 2-Pentanone, 4-hydroxy-4-methyl- 0,585
8 3,16 0,64 Benzene, 1,3-dimethyl- 0,513
9 4,28 0,66 1,3-Cyclohexadiene, 1,5,5,6-tetrame 0,529
10 5,43 0,69 Isoterpinolene 0,553
11 6,48 22,22 Benzene, 1,2,4-trimethyl- 18,259
12 8,25 0,42 Cyclohexanone, 3,3,5-trimethyl- 0,337
13 9,88 0,65 Phenol, 3-methyl- 0,521
14 9,97 0,89 Benzene, 1,2,3,5-tetramethyl- 0,713
15 10,05 2,13 2-Cyclohexen-1-one, 3,5,5-trimethyl 1,707
16 10,12 3,1 Furan, 3-pentyl- 2,484
17 11,24 5,63 Phenol, 2,5-dimethyl- 4,511
18 12,56 0,35 Benzene, 1-(2-butenyl)-2,3-dimethyl 0,280
100
T=573 K, P=100 atm, F=0.4 ml/min
Pk# RT Area% Library/ID Molar
Fraction
1 0,83 3,19 Carbon dioxide 2,673
2 0,94 96,81 2-Propanone 81,112
3 1,2 87,81 Acetic acid 16,215
100
T=623 K, P=100 atm, F=0.4 ml/min
73
Pk# RT Area% Library/ID Molar
Fraction
1 0,85 98,67 2-Propanone 85,074
2 5,25 1,33 Benzene, 1,3,5-trimethyl- 1,147
3 7,31 72,51 Acetic acid 13,779
100
T=673 K, P=100 atm, F=0.4 ml/min
Pk# RT Area% Library/ID Molar
fraction
1 0,8 18,33 Carbon dioxide 15,911
2 0,86 71,85 2-Propanone 62,369
3 1,44 7,44 3-Hexen-2-one 6,458
4 5,16 2,39 Benzene, 1,2,3-trimethyl- 2,075
5 6,45 68,93 Acetic acid 13,188
100,000
T=723 K, P=100 atm, F=0.4 ml/min
Pk# RT Area% Library/ID Molar
Fraction
1 0,86 16,78 1-Propene, 2-methyl- 15,185
2 0,92 27,82 2-Propanone 25,176
3 1,12 1,16 2-Butanol 1,050
4 1,93 1,92 5-Hexen-2-one 1,738
5 2,53 9,47 tert-Butylketene 8,570
6 2,6 0,88 2-Hexanol 0,796
7 3,62 0,29 2-Pentanone, 4-hydroxy-4-methyl- 0,262
8 4,53 0,91 3-Hexanol, 2-methyl- 0,824
9 4,93 2,25 2,6,6-Trimethyl-3-methylenecyclohex 2,036
10 5,12 4,34 2-Heptanol 3,928
11 5,68 0,31 1,4-Cyclohexadiene, 3,3,6,6-tetrame 0,281
12 5,97 1,01 cis-3a-Methyl-2,3,4a,6,7,7a-hexahyd 0,914
13 6,9 15,88 Benzene, 1,3,5-trimethyl- 14,371
14 7,53 1,38 4-Octanol 6,127
15 8,5 0,21 Cyclohexanone, 3,3,5-trimethyl- 0,190
16 9,25 0,22 4-Octanone, 7-methyl- 0,199
17 9,69 2,85 4-Nonanol 2,833
18 10,09 0,3 Benzene, 1,2,3,5-tetramethyl- 0,271
19 10,25 3,85 2-Cyclohexen-1-one, 3,5,5-trimethyl 3,484
74
20 11,33 1,83 Phenol, 3,5-dimethyl- 1,656
21 12,6 0,35 Benzene, 1,2,4-trimethyl-5-(1-methy 0,317
22 16,53 0,35 1,2-DIHYDRO-4-ETHYL-5-METHYLPYRROLO 0,317
23 18,34 47,51 Acetic acid 9,476
100
T=623 K, P=100 atm, F=0.6 ml/min
Pk# RT Area% Library/ID Molar
fraction
1 0,84 35,87 Propanone 30,167
2 0,89 64,13 2-Propanone 53,933
3 1,12 85,78 Acetic acid 15,900
100
T=673 K, P=100 atm, F=0.6 ml/min
Pk# RT Area% Library/ID Molar
fraction
1 0,84 93,73 2-Propanone 79,986
2 1,74 0,52 3-Penten-2-one, 4-methyl- 0,444
3 1,82 1,62 3-Hexen-2-one 1,382
4 3,42 0,54 4-Heptanol 0,461
5 3,75 2,31 2-Heptanol 1,971
6 5,86 0,48 Benzene, 1,2,4-trimethyl- 0,410
7 7,04 0,36 3-Octanol 0,307
8 9,35 0,44 4-Octanol, 7-methyl- 0,375
9 10,91 77,96 Acetic acid 14,663
100,000
T=723 K, P=100 atm, F=0.6 ml/min
Pk# RT Area% Library/ID Molar
fraction
1 0,81 20,88 Carbon dioxide 18,898
2 0,89 39,25 2-Propanone 35,525
3 1,88 9,92 3-Hexen-2-one 8,979
4 2,03 1,02 3-Hexen-2-one 0,923
5 2,69 0,55 2-Pentanone, 4-hydroxy-4-methyl- 0,498
6 3,97 2,98 2-Hexanol 2,697
7 4,11 2,09 2-Heptanol 1,892
8 5,12 0,63 ,alpha,-Terpinene 0,570
75
9 6,21 12,12 Benzene, 1,2,4-trimethyl- 10,970
10 7,02 0,46 4-Octanol 0,416
11 7,08 0,45 4-Octanol 0,407
12 7,19 0,7 3-Octanol 0,634
13 7,26 0,82 3-Octanol 0,742
14 7,34 0,58 2-Octanol 0,525
15 7,41 1,25 2-Octanol 1,131
16 9,45 1,72 4-Nonanol 1,557
17 9,89 0,34 Benzene, 1,2,3,5-tetramethyl- 0,308
18 10,01 2,59 2-Cyclohexen-1-one, 3,5,5-trimethyl 2,344
19 11,24 1,66 Phenol, 3,5-dimethyl- 1,502
20 13,34 47,53 Acetic acid 9,482
100
T=573 K, P=100 atm, F=0.8 ml/min
Pk# RT Area% Library/ID Molar
fraction
1 0,84 37,58 2-Propanone 31,773
2 0,87 60,76 2-Propanone 51,371
3 6,41 1,66 Benzene, 1,2,4-trimethyl- 1,403
4 8,29 82,92 Acetic acid 15,452
100
T=673 K, P=100 atm, F=0.8 ml/min
Pk# RT Area% Library/ID Molar
fraction
1 0,83 5,45 Carbon dioxide 4,653
2 0,86 1,59 1-Propene, 2-methyl- 1,357
3 0,94 66,05 2-Propanone 56,386
4 2,05 5,1 2-Pentanol 4,354
5 2,85 1,26 3-Hexanol 1,076
6 2,93 1,59 2-Pentanol, 4-methyl- 1,357
7 4,91 1,7 4-Heptanol 1,451
8 5,14 0,97 2-Heptanol 0,828
9 5,38 8,31 2-Heptanol 7,094
10 7,63 1,05 4-Octanol 0,896
11 7,79 1,68 3-Octanol 1,434
12 7,92 1,45 2-Octanol 1,238
13 9,72 3,17 2,3-Octanediol 2,706
14 9,9 0,64 2-Nonanol 0,546
76
15 12,76 77,72 Acetic acid 14,623
100
T=723 K, P=100 atm, F=0.8 ml/min
Pk# RT Area% Library/ID Molar
fraction
1 0,82 27,4 2-Propanone 24,101
2 0,85 51,85 2-Propanone 45,608
3 1,29 7,23 3-Hexen-2-one 6,360
4 2,34 1,28 2-Heptanol 1,126
5 4,5 10,35 Benzene, 1,3,5-trimethyl- 9,104
6 9,45 1,1 2-Cyclohexen-1-one, 3,5,5-trimethyl 0,968
7 10,9 0,79 Phenol, 2,4-dimethyl- 0,695
8 13,45 62,1 Acetic acid 12,039
100
T=573 K, P=100 atm, F=1.0 ml/min
Pk# RT Area% Library/ID Molar
fraction
1 0,79 24,06 2-Propanone 56,977
2 1,86 4,59 3-Hexen-2-one 4,205
3 2,7 1,09 2-Pentanone, 4-hydroxy-4-methyl- 0,998
4 2,89 0,48 Benzene, 1,3-dimethyl- 0,440
5 5,09 0,31 ,alpha,-Terpinene 0,284
6 6,17 17,63 Benzene, 1,3,5-trimethyl- 16,149
7 6,46 0,27 1-Heptanol 0,247
8 6,84 0,59 Benzene, 1,2,3-trimethyl- 0,540
9 9,68 0,38 Phenol, 3-methyl- 0,348
10 9,78 0,53 Phenol, 4-methyl- 0,485
11 9,88 1,77 Benzene, 1,2,3,4-tetramethyl- 1,621
12 10,03 3,14 2-Cyclohexen-1-one, 3,5,5-trimethyl 2,876
13 11,18 7,03 Phenol, 2,5-dimethyl- 6,440
14 14,23 41,55 Acetic acids 8,389
100
T=623 K, P=100 atm, F=1.0 ml/min
Pk# RT Area% Library/ID Molar
fraction
1 0,81 15,12 Carbon dioxide 12,512
2 0,83 3,21 2-Propanone 2,656
77
T=673 K, P=100 atm, F=1.0 ml/min
Pk# RT Area% Library/ID Molar
fraction
1 0,77 1,22 Ammonia 1,033
2 0,82 35 Carbon dioxide 29,647
3 0,87 54,85 2-Propanone 46,461
4 2,19 1,69 3-Penten-2-one, 4-methyl- 2,211
5 3,35 81,92 Acetic acid 15,294
6 6,46 4,8 Benzene, 1,2,3-trimethyl- 4,066
7 9,99 0,62 Benzene, 1,2,3,4-tetramethyl- 0,525
8 10,09 0,9 2-Cyclohexen-1-one, 3,5,5-trimethyl 0,762
100
T=723 K, P=100 atm, F=1.0 ml/min
Pk# RT Area% Library/ID Molar
fraction
1 0,79 16,48 Carbon dioxide 14,547
2 0,85 67,46 2-Propanone 59,547
3 1,29 14,27 3-Hexen-2-one 12,596
4 4,44 1,78 Benzene, 1,3,5-trimethyl- 1,571
5 6,86 60,34 Acetic acid 11,739
100
T=573 K, P=200 atm, F=0.2 ml/min
Pk# RT Area% Library/ID Molar
fraction
1 0,79 1,65 2-Propanone 1,377
2 0,93 98,35 2-Propanone 82,070
3 1,24 90 Acetic acid 16,553
100
T=623 K, P=200 atm, F=0.2 ml/min
Pk# RT Area% Library/ID Molar
fraction
1 0.97 100 2-Propanone 83,892
3 0,91 79,6 2-Propanone 65,868
4 6,8 2,07 Benzene, 1,2,4-trimethyl- 1,713
5 8,34 94,59 Acetic acid 17,251
100
78
2 1,35 87,12 Acetic acid 16,108
100
T=673 K, P=200 atm, F=0.2 ml/min
Pk# RT Area% Library/ID Molar fraction
1 0,92 86,15 2-Propanone 72,591
2 2,55 4,29 3-Hexen-2-one 4,963
3 2,96 84,75 Acetic acid 15,739
4 3,51 1,28 2-Pentanone, 4-hydroxy-4-methyl- 1,079
5 6,78 6,68 Benzene, 1,2,4-trimethyl- 5,629
100
T=723 K, P=200 atm, F=0.2 ml/min
Pk# RT Area% Library/ID Molar
fraction
1 0,88 23,65 2-Propanone 21,351
2 0,91 22,4 No matches found 20,223
3 1,1 0,38 2-Butanone 0,343
4 2,54 9,16 3-Hexen-2-one 8,270
5 3,65 0,76 2-Pentanone, 4-hydroxy-4-methyl- 0,686
6 3,7 0,37 Benzene, 1,3-dimethyl- 0,334
7 4,92 1,67 1,3-Cyclohexadiene, 1,5,5,6-tetrame 1,508
8 5,66 0,57 1,4-Cyclohexadiene, 3,3,6,6-tetrame 0,515
9 5,97 1,73 Isoterpinolene 1,562
10 7 32,6 Benzene, 1,3,5-trimethyl- 29,432
11 7,41 0,47 Benzene, 1,2,3-trimethyl- 0,424
12 8,48 0,44 Cyclohexanone, 3,3,5-trimethyl- 0,397
13 10,1 1,37 Benzene, 1,2,3,4-tetramethyl- 1,237
14 10,24 3,23 2-Cyclohexen-1-one, 3,5,5-trimethyl 2,916
15 11,27 0,87 Phenol, 2,5-dimethyl- 0,785
16 12,59 0,34 (Z)-2-(1'-PROPENYL)MESITYLENE 0,307
17 14,78 48,8 Acetic acid 9,710
100
T=573 K, P=200 atm, F=0.4 ml/min
Pk# RT Area% Library/ID Molar
fraction
1 0.94 100 2-Propanone 82,990865
2 1,45 92,99 Acetic acid 17,009135
79
T=623 K, P=200 atm, F=0.4 ml/min
Pk# RT Area% Library/ID Molar
fraction
1 0,79 21,43 Carbon dioxide 18,524
2 0,82 78,57 2-Propanone 67,915
3 1,67 71,18 Acetic acid 13,561
100
T=673 K, P=200 atm, F=0.4 ml/min
Pk# RT Area% Library/ID Molar
fraction
1 0.81 100 2-Propanone 85,1847
2 0,96 78,91 Acetic acid 14,8153
100
T=723 K, P=200 atm, F=0.4 ml/min
Pk# RT Area% Library/ID Molar
fraction
1 0,8 9,88 Carbon dioxide 8,562
2 0,84 61,17 2-Propanone 53,012
3 1,59 13,89 3-Hexen-2-one 12,038
4 2,16 1,4 2-Pentanone, 4-hydroxy-4-methyl- 1,213
5 5,72 13,66 Benzene, 1,3,5-trimethyl- 11,838
6 6,12 69,82 Acetic acid 13,336
100
T=573 K, P=200 atm, F=0.6 ml/min
Pk# RT Area% Library/ID Molar
fraction
1 0,88 57,55 Ammonia 48,590
2 0,94 42,45 2-Propanone 35,841
3 1,59 83,66 Acetic acid 15,568
100
T=623 K, P=200 atm, F=0.6 ml/min
Pk# RT Area% Library/ID Molar
fraction
1 0,8 24,88 Carbon dioxide 21,291
2 0,84 75,12 2-Propanone 64,283
3 1,45 76,49 Acetic acid 14,426
100
80
T=723 K, P=200 atm, F=0.6 ml/min
Pk# RT Area% Library/ID Molar
fraction
1 0,82 29,52 2-Propanone 75,190
2 0,96 66,39 Acetic acid 12,764
3 1,42 6,29 3-Hexen-2-one 5,487
4 1,82 2,07 2-Pentanone, 4-hydroxy-4-methyl- 1,806
5 5,1 4,89 Benzene, 1,2,3-trimethyl- 4,265
6 9,64 0,56 2-Cyclohexen-1-one, 3,5,5-trimethyl 0,488
100
T=573 K, P=200 atm, F=0.8 ml/min
Pk# RT Area% Library/ID Molar
fraction
1 0,86 27,15 Propanone 55,065
2 1,75 84,99 Acetic acid 15,864
3 2,03 5,98 2-Pentanol 5,030
4 2,84 1,9 3-Hexanol 1,598
5 2,91 1,93 2-Hexanol 1,624
6 4,87 1,9 4-Heptanol 1,598
7 5,07 0,89 Ethanol, 2-(2-methoxyethoxy)- 0,749
8 5,3 8,35 2-Heptanol 7,024
9 7,62 1,28 4-Octanol 1,077
10 7,77 2,03 3-Octanol 1,708
11 7,89 1,63 2-Octanol 1,371
12 9,73 5,35 4-Octanol, 7-methyl- 4,500
13 9,82 0,19 3-Nonanol 0,160
14 9,91 1,01 2-Nonanol 0,850
15 11,39 1,38 5-Decanol 1,161
16 12,9 0,74 1,2-Heptanediol 0,622
100
T=623 K, P=200 atm, F=0.8 ml/min
Pk# RT Area% Library/ID Molar
fraction
1 0.81 40 Carbon dioxide 33,9577
2 0.86 60 2-Propanone 50,9366
3 0,94 80,19 Acetic acid 15,1056
100
81
T=673 K, P=200 atm, F=0.8 ml/min
Pk# RT Area% Library/ID Molar
fraction
1 0,81 42,71 Carbon dioxide 35,907
2 0,86 57,29 2-Propanone 48,165
3 1,14 85,38 Acetic acid 15,928
100
T=723 K, P=200 atm, F=0.8 ml/min
Pk# RT Area% Library/ID Molar
fraction
1 0,8 34,5 2-Propanone 74,877
2 0,88 73,87 Acetic acid 14,083
3 1,71 4,6 3-Penten-2-one, 4-methyl- 6,384
4 2,38 1,36 2-Pentanone, 4-hydroxy-4-methyl- 1,168
5 5,85 3,5 Benzene, 1,2,4-trimethyl- 3,007
6 9,89 0,56 2-Cyclohexen-1-one, 3,5,5-trimethyl 0,481
100
T=573 K, P=200 atm, F=1.0 ml/min
Pk# RT Area% Library/ID Molar
fraction
1 0,84 3,36 Carbon dioxide 2,900
2 0,85 5,53 Ammonia 29,107
3 2,24 8,73 2-Pentanol 7,536
4 2,41 0,15 Octane 0,129
5 2,94 1,19 2-Hexanol 5,870
6 4,57 0,11 Nonane 0,095
7 5,11 2,48 4-Heptanol 15,865
8 5,24 1,38 2-Propanol 1,191
9 6,65 0,12 4-Octanol 7,656
10 6,77 0,15 Benzene, 1,3,5-trimethyl- 0,129
11 9,85 9,36 4-Octanol, 7-methyl- 8,079
12 9,93 0,61 3-Nonanol 2,184
13 10,03 71,43 Acetic acid 13,681
14 11,46 2,68 6-Dodecanol 2,313
15 11,56 0,48 3-Heptanol 0,414
16 12,94 3,07 1,2-Heptanediol 2,650
17 14,27 0,23 6-Dodecanol 0,199
100
82
T=623 K, P=200 atm, F=1.0 ml/min
Pk# RT Area% Library/ID Molar
fraction
1 0,84 34,87 Ammonia 29,479
2 0,89 65,13 2-Propanone 55,060
3 1,25 82,42 Acetic acid 15,461
100
T=673 K, P=200 atm, F=1.0 ml/min
Pk# RT Area% Library/ID
Molar
fraction
1 0,8 30,08 Carbon dioxide 25,807
2 0,85 49,74 2-Propanone 42,674
3 1,95 1,7 3-Hexen-2-one 1,459
4 2,72 0,79 2-Pentanone, 4-hydroxy-4-methyl- 0,678
5 5,22 0,72 Alloocimene 0,618
6 6,24 9,74 Benzene, 1,2,3-trimethyl- 8,356
7 9,91 1,87 Benzene, 1,2,3,5-tetramethyl- 1,604
8 10,02 1,69 2-Cyclohexen-1-one, 3,5,5-trimethyl 1,450
9 11,15 3,67 Phenol, 2,5-dimethyl- 3,149
74,62 Acetic acid 14,205
100
T=723 K, P=200 atm, F=1.0 ml/min
Pk# RT Area% Library/ID Molar
fraction
1 0,8 29,73 Carbon dioxide 26,156
2 0,87 12,85 2-Propanone 11,305
3 1,46 1,7 5-Hexen-2-one 9,106
4 2,68 0,83 2-Pentanone, 4-hydroxy-4-methyl- 0,730
5 2,95 0,53 Benzene, 1,3-dimethyl- 0,466
6 3,74 0,2 2,2-Dimethyl-1-isopropenyl-cyclopen 0,176
7 4,01 1,49 1,3-Cyclohexadiene, 1,5,5,6-tetrame 1,311
8 4,76 0,45 Tricyclo[3,1,0,0(2,4)]hexane, 3,3,6 0,396
9 5,16 1,52
2,2,3-TRIMETHYL-1-VINYL-3-
CYCLOPENT 1,337
10 6,28 27,59 Benzene, 1,2,3-trimethyl- 25,259
11 8,59 0,22 Benzene, 1-methyl-4-(1-methylethyl) 0,194
83
12 9,73 0,18 Phenol, 4-methyl- 0,158
13 9,81 1 Benzene, 1,2,3,5-tetramethyl- 0,880
14 9,91 3,19 Benzene, 1,2,3,4-tetramethyl- 3,097
15 10,03 4,16 2-Cyclohexen-1-one, 3,5,5-trimethyl 3,660
16 11,15 2,89 Phenol, 3,5-dimethyl- 2,543
17 11,51 0,18 Benzene, 1-(2-butenyl)-2,3-dimethyl 0,484
18 13,28 0,31 1-Butyl-2,3,6-trimethylbenzene 0,554
19 13,55 61,49 Acetic acid 12,004
20 16,5 0,21 3-o-Methoxyphenyl-pyridine 0,185
100
84
APPENDIX D
MATLAB®
code
clc;
clear all;
'MaxIter',100000000,...
'TolX',1e-4,... %default: 1e-4
'LevenbergMarquardt','on',... %default: on
'LargeScale','on',... %default: on
'MaxFunEvals',1E1000050,...;
global data
data=[
%Rexp %Pa %Pw %Pc %Temperature
0.829 12.182 0 0 573
%0.840 131.971 0 0
%0.847 880.94 0 0
%0.853 1093.887 0 0
0.840 12.343 0 0 573
0.847 12.446 0 0 573
0.853 12.534 0 0 573
0.894 13.137 0 0 573
%0.839 1202.36 0 0
%0.848 976.32 0 0
0.839 12.329 0 0 623
0.848 12.461 0 0 623
0.851 12.505 0 0 623
%0.875 167.12 0 0
0.875 12.858 0 0 623
0.900 13.225 0 0 623
%0.846 1103.11 0 0
0.846 12.431 0 0 673
0.855 12.564 0 0 673
%0.875 167.116 0 0
%0.913 177.293 0 0
0.875 12.858 0 0 673
0.913 13.416 0 0 673
0.934 13.725 240.347 14 673
%0.865 605.162 0 0
85
%0.877 1270.53 0 0
0.865 12.711 0 0 723
0.877 12.887 0 0 723
0.900 13.225 177.293 17 723
%0.925 162.133 49.061 0
%0.952 132.488 0 0
0.925 13.592 49.061 0 723
0.952 12.989 0 0 723
];
% experimental data
data1=[
%Rexp
0.829
0.840
0.847
0.853
0.894
0.839
0.848
0.851
0.875
0.900
0.846
0.855
0.875
0.913
0.934
0.865
0.877
0.900
0.925
0.952
];
Rexp=data(:,1);
Pa=data(:,2);
Pw=data(:,3);
Pc=data(:,4);
T=data(:,5);
86
b0=[
3822
10.4249
%0.972548763763648
1.047236081
%0.970198731337977
1.008638298
%1.00030715356418
1.067988632
%1.04628462455179
1.038752445
];
LB=[0,0,0,0,0,0];
UB=[Inf,Inf,Inf,Inf,Inf,Inf];
[b,resnorm]=lsqnonlin('recfun2',b0,LB,UB)
[b,r,J,SIGMA]=nlinfit(data,data1,'recfun',b0)
bci=nlparci(b,r,J)
newX = data(:,:);
[YPRED, DELTA] = NLPREDCI('recfun',newX,b,r,'jacobian',J)
%Rcal= (b(1).*(Pa.^2))./ (1+b(2).*Pa + b(3).*Pw + b(4).* Pc).^2;
%Rcal=(b(1).*((b(2).^2*Pa.^2)-
((Pa.*Pc.*Pw)./(b(3).*b(4).*b(5))))./(1+sqrt((Pa.*Pc.*Pw)./(b(3).*b(4).*b(5))+(Pc./b(4)
)+(Pw./b(5))).^2));
Rcal=(b(1).*exp(b(2)/(T.*0.082))*((b(3).^2*Pa.^2)-
((Pa.*Pc.*Pw)./(b(4).*b(5).*b(6))))./(1+sqrt((Pa.*Pc.*Pw)./(b(4).*b(5).*b(6))+(Pc./b(5)
)+(Pw./b(6))).^2))