Upgrading the bottom of the barrel through in situ oil recovery (THAI CAPRI) process

Upgrading the bottom of the barrel
through in-situ oil recovery (THAI CAPRI)
process
By
Sinthujan Pushpakaran
School of Chemical Engineering
College of Engineering and Physical Science
University of Birmingham
August 2017

Abstract
As world reserves of light crude oil are gradually running out, alternative vast
deposits of heavy oil and bitumen have been considered to balance rising fuels demand.
Heavy oil and bitumen are characterised by high viscosity, high density, low API gravity, low
yields of low – boiling fuel distillates and high heteroatom content which make it challenging
for industrial use. Upgrading is the breakdown of heavy oil into oil that features similar
characteristics to light oils. The THAI – CAPRI (Toe – to – heel air injection with catalytic
upgrading process in-situ) aims at accomplishing upgrading down – hole. In light of catalyst
deactivation issues with hydrodesulphurization (HDS) catalysts highlighted in previous THAI
– CAPRI process studies, novel synthetic NiAlCO3-HTlc anionic clays catalysts at different
concentrations are explored with aim of controlling catalyst deactivation due to coking while
enhancing level of upgrading. In this study, the THAI – CAPRI process was replicated using
a batch autoclave reactor. Effects of increasing catalyst concentration of NiAlCO3-HTlc
anionic clay catalysts on the extent of upgrading were investigated via thermal cracking
upgrading experiments carried out at 425 °C to evaluate performance. It was found that at
high reaction temperature of 425 °C, cracking deteriorated as well as decrease in API gravity
(6 to 2°), viscosity reduction of (99.5 to 99.1 %) and lower yield of fuel distillates with
increasing catalyst concentration. Despite improvement in produced oil in the 2:1 NiAlCO3-
HTlc anionic clay catalyst, coke content of spent catalysts reduced from 33.2 to 24.4 wt. %
as catalyst concentration increased. A reduction in asphaltene content with increasing
catalyst concentration was also noted. The synergistic effect of increasing nickel content
lessen level of upgrading and diminishes oil production, detriments pipeline transportation
via increment in viscosity, however produces less impurities thus reducing impact on the
environment and downstream processes. The yield of fuel distillates increased with
increasing catalyst concentration of NiAlCO3-HTlc.

Acknowledgements
I would never have been able to complete this thesis without the guidance of my
committee members and support from friends and family.
I would like to express my deepest gratitude to my supervisor, Prof. Joseph Wood,
for choosing me for this research project and his leadership in supervising the study with
patience and constructive comments. I would like to thank Dr. Abarasi Hart in assisting the
co – supervision of this study and providing immeasurable help throughout these last three
months with valuable comments and discussion. I would also like to thank, Mr. Ryan
Claydon in his support throughout the study, aiding me in the right direction and allowing me
to contribute to his PhD. Last but not least, I would like to thank Marcin Konarski for being
such a valuable laboratory partner and good friend, always willing to help and share his
suggestions.
Most importantly, I would like to thank all my friends who have helped me get through
this Master’s degree. The Coombe family, Birunda, Duckshini, Shanju, Stephanie, Tahmidur,
Vahini, Vasuki and Vishal with their constant support no matter what the situation. The duo
of Bashine and Hanna who have helped me keep my life in context. The Thwaite team,
Albert, Emmanuel, Marwah, Nikita, Ruchir, Semra and Simukai who have always not failed
in providing a good laugh whilst writing this thesis. Members of the University of Hull with
their continuous support in whatever assignment I am involved in and lastly, I would like to
thank members of the University of Birmingham Tamil Society and MSc Advanced Chemical
Engineering class for enriching my postgraduate life here at the University of Birmingham
and making my last year at University a one to remember.
Finally, I would like to express the outmost gratitude to my parents and my sister for
forever believing in me and providing me all the necessary help throughout my studies as
without them I would have not been able to pursue this Master’s degree.

Table of Contents
1. Introduction........................................................................................................... 1
1.2 Research Aims and Objectives........................................................................... 4
2. Materials and methods……………………………………………………………… 5
2.2 Materials…..…………………............................................................................. 5
2.2.1 Nickel (II) Nitrate Hexahydrate................................................................ 5
2.2.2 Aluminium (III) Nitrate Nonahydrate..……………………………………... 6
2.2.3 Ammonium Carbonate......……………………………………………....... 7
2.2.4 Ammonium Hydroxide.............................................................................8
2.2.5 Heavy Oil Feedstock...............................................................................8
2.2.6 Carbon Disulphide.................................................................................. 10
2.2.7 Hexane .................................................................................................11
2.3 Formulation of Hydrotalcite Catalyst ....................................................................11
2.3.1 Hydrotalcite synthesis............................................................................. 11
2.3.2 XRD of Hydrotalcite Catalysts..................................................................13
2.4 Experimental Procedure for Upgrading Experiments.............................................14
2.5 Analytical Instruments .........................................................................................16
2.5.1 Density and API Gravity Measurement..................................................... 16
2.5.2 Viscosity Measurement .......................................................................... 17
2.5.3 Asphaltene Content Measurement .......................................................... 19
2.5.4 True Boiling Point (TBP) Distribution ........................................................19
2.5.5 Thermogravimetric Analysis (TGA) ..........................................................21
3. Results and Discussion ....................................................................................... 23
3.1 Characterisation of Hydrotalcites via X-ray Powder Diffraction ............................. 23
3.2 Effect of Diverse Ni/Al Molar Ration on Upgraded Oil Mass Balance .................... 26
3.3 Effect of Diverse Ni/Al Molar Ratios of Hydrotalcites on API Gravity and Viscosity.29

3.4 Effect of Diverse Ni/Al Molar Ratios of Hydrotalcites on TBP Distribution...............33
3.5 Effect of Diverse Ni/Al Molar Ratios of Hydrotalcites on Spent Catalyst Coke
Content............................................................................................................................. 37
3.6 Effect of Diverse Ni/Al Molar Ratios of Hydrotalcites on Asphaltenes Content ...... 40
4. Conclusion and Recommendations.....................................................................41
Bibliography ......................................................................................................................44
Appendix A Upgrading Process of Thermal Cracking and Catalytic Upgrading .......... 49
Appendix B Calculation of API Gravity and Change in API Gravity...............................51
Appendix C Calculation of Viscosity and Degree of Viscosity Reduction (DVR) ......... 54
Appendix D Calculation of Asphaltene Content ............................................................ 60
Appendix E Calculation of Lattice Parameter, Average Crystallite Size and Unit Cell
Dimension....................................................................................................62
Appendix F Mass Balance Calculations ........................................................................ 66
Appendix G Thermogravimetric Graphs ........................................................................ 75

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1. Introduction
Oil demand has been projected to reach 111.1 million barrels per day by 2040 by the
Organization of the Petroleum Exporting Countries (OPEC), equivalent to a 23.1% compared
to current data (OPEC, 2014). The global society requires fuel for cooking, transport and
heating. Furthermore, hydrocarbons are the primary feedstock for the world’s chemical
industries. Henceforth, oil demand is progressively increasing, however consumption of
conventional light oil has not decelerated (Shah et al., 2010). Despite light oils’ high
efficiency, they have heavily contributed to the decline of the world’s remaining oil reserves,
thus exploration of vast deposits of heavy oil and bitumen is an alternative option to balance
the rising demand (Hirsch et al., 2006). Heavy oils are the largest petroleum resources found
on this planet and as estimated by the International Energy Agency (IEA) they account for
nearly 5.5 trillion barrels. Major reserves are found in the Orinoco heavy-oil belt, Venezuela
and Alberta, Canada with estimated reserves of 3,396 and 5,505 billion barrels respectively
(Shah et al., 2010). Bitumen and heavy oil roughly constitute 70% of the world’s total oil
resources, equivalent to 9-13 trillion barrels as reported by Zhang et al. (2012). Based on
these figures, reserves of non-conventional heavy oil resources prevail over conventional
light crude oil reserves, which are estimated to be 1.02 trillion barrels (Hein, 2006).
Although large non-conventional oil resources are present, several challenges have
been highlighted for their exploitation, these include high capital and energy intensive
extraction, greenhouse gas emissions from production, technical challenges in regard to
transportation and upgrading of conventional crude oil is more economical than upgrading of
heavy crude oil, however market value of non-conventional oil is low compared to light crude
oil. Much of the reason for high cost and technical challenges facing extraction and refining
are due to the characteristics of heavy crude oil, which include high density/low API gravity,
high viscosity and high asphaltenes. To obtain characteristics for refining processes, heavy
oil/bitumen requires further processing by means of an upgrading process which convert
heavy crude oil to synthetic oil by means of characteristics such as API gravity, viscosity and

2
heteroatom qualities that resemble light crude oil (Carrillo and Corredor, 2012). Manufacture
of synthetic crude oil suitable for refining is obtained through combination of several surface
upgrading processes such as catalytic cracking, delayed coking, solvent deasphalting and
hydroconversion processes. However, these processes greatly impact the environment
through emission of greenhouse gases and low conversions and high yield of undesirable
by-product coke are observed (Furimsky, 2009), henceforth, studies in respect to in situ
upgrading technologies, which comprise conversion of heavy crude oil to light oil prior to
reaching the surface are particularly emphasised. Capital expenditure of heavy oil and
bitumen exploration is attributed to the additional cost imposed by surface upgrading
facilities (Atkins, 2011), thus economics of heavy oil and bitumen resources has the potential
to be improved through development of efficient in situ upgrading technologies.
Light crude oil is produced via primary and secondary methods before declining of
reservoir energy, however heavy oil/bitumen are produced via thermal and/or solvent
stimulation of the reservoir, known as Enhanced Oil Recovery (EOR) techniques, which are
further classified as steam-based and in-situ combustion techniques. Examples of steam-
based methods include Cyclic Steam Stimulation (CSS) and Steam Assisted Gravity
Drainage (SAGD) and in-situ combustion processes are termed in Situ Combustion (ISC)
and the novel Toe-to-Heel Air Injection (THAI) with its catalytic upgrading process in-situ
(CAPRI). The aforementioned processes are dependent on viscosity reduction through
heating for improvement in oil fluidity and production, however steam processes require
large amounts of water to produce a barrel of oil, thus proving to be unfeasible whilst
affecting the environment (Gates and Chakrabarty, 2006).
Several advantages are perceived by the downhole in situ upgrading of heavy
oil/bitumen which include production of low viscosity oil, use of available heat and gases and
minimisation of surface upgrading (Xia et al., 2002). The THAI process utilises a horizontal
producer well instead of a vertical producer well often utilised in conventional ISC (in situ
combustion) methods, thus meaning that combustion propagates across the horizontal
producer well (Greaves et al., 2001). The methodology behind toe-to-heel injection lies in the

3
introduction of air through a horizontal well based on the in-line positioning of the horizontal
well and reservoir (Greaves and Xia, 2001). Vertical injection orientation is also possible,
however this is only viable if good distribution of gas in the reservoir is achieved from
horizontal to vertical permeability. However, a horizontal injector is more suitable as Greaves
et al. (2001) report that uniform distribution of air across inlet reservoir face of line drive
section is attained. A representation of the THAI process is highlighted in Figure 1.1.
Measurement of heavy oil upgrading is achieved through improvement in viscosity,
API gravity and reduction of asphaltenes and hetero-atoms (Ovalles and Rodriguez, 2008).
A 3-D physical model study of catalytic upgrading of Wolf lake heavy oil using THAI-CAPRI
conducted by Xia and Greaves (2001) highlighted an increase of 9° in API gravity from the
produced oil attained by thermal cracking upgrading via THAI. In addition, a further increase
in API gravity by 3-7° was observed when incorporating CAPRI, thus it can be highlighted
that upgrading of heavy oil to light oil is achievable through a single step down-hole process.
Further research by Shah et al. (2011) report detailed optimisation of process variables such
as reaction temperature, pressure, oil flow rate and gas-to-oil ratio that are to be
implemented in the CAPRI process. The study highlighted an optimum reaction temperature

4
of 425 °C, oil flow rate of 1 mL.min-1
and catalyst deactivation as a result of coke and metal
deposits on the catalyst during reaction, thus the primary objective of this study was to
extend lifetime of catalyst whilst improving upgrading reaction. However, packing of well with
commercial pelleted hydrodesulphurisation catalyst is necessary for CAPRI yet it has been
linked with issues in regards to catalyst deactivation. Henceforth, the challenges facing the
packing of the horizontal producer well and catalyst deactivation may be resolved through
implementation of synthetic hydrotalcites with tailored properties of upstream oil upgrading
catalysts. The proposed technologies will aim to reduce environmental impact associated
with mining and steam injection, however catalyst lifetime maybe unfeasible by coking and
deactivation, thus opportunity for innovative solutions that are applicable in the well are
pursued.
1.2 Research Aims and Objectives
In addition to improving API gravity and viscosity of oil for promotion of pipeline
transportation, the THAI-CAPRI process also aims to remove impurities and provide
feedstock that meet downstream and refinery specification. Furthermore, hydrotalcite
catalysts with an enhanced ability to upgrade heavy oil and their combination with in situ
techniques for the reduction of energy required to recover a barrel of oil will be investigated.
The specific objectives outlined in the current study were:
• To synthetize anionic clays (NiAlCO3- HTlc) with different Ni/Al concentrations
through a co-precipitation method as effective in situ upgrading catalysts.
• To investigate recovery/upgrading to produce oil with increased API gravity and lower
viscosity.
• To investigate effectiveness and performance of hydrotalcite catalysts in upgrading
process.

5
2. Materials and methods
2.2 Materials
The following chemical compounds were utilised in the formulation of anionic clay catalysts,
feedstock for reaction process and as reagents for the characterisation techniques utilised.
2.2.1 Nickel (II) Nitrate Hexahydrate

6
2.2.2 Aluminium (III) Nitrate Nonahydrate

8
2.2.4 Ammonium Hydroxide
2.2.5 Heavy Oil Feedstock
Feedstock oil utilised for thermal cracking and catalytic upgrading experiments was
provided by Touchstone Exploration Inc, from THAI field operations located in Kerrobert,
Saskatchewan, Canada. Properties of feed oil are presented in Table 2.5.

11
2.2.7 Hexane
2.3 Formulation of Hydrotalcite Catalyst
2.3.1 Hydrotalcite synthesis
Preparation of NiAlCO3-HTlcs was achieved through a co-precipitation method at low
supersaturation, at constant pH. Ideal conditions for the co-precipitation method at low
supersaturation as reported by Falconi et al. (1991) are: temperature 60-80 °C, pH ranging
from 7 to 10, low concentration of reagents and low flow of two streams. Low
supersaturation conditions ease formation of precipitates that highlight a more crystalline
structure with respect to those attained at high supersaturation conditions due to rate of

12
nucleation being higher than rate of crystal growth, although a large number of particles are
formed, these are smaller in size (Courty et al., 1982; Gaigneaux, 2010).
The study focused on the preparation of NiAlCO3- HTlc with different Ni to Al molar
ratios, respectively being 2:1, 3:1 and 4:1. The formulation method was the same for each
NiAlCO3- HTlc. Known quantities of Ni(NO3)2.6H2O and Al(NO3)2.9H2O were dissolved in 100
ml of water. A separate solution of Na2CO3 was prepared through addition of a known
quantity of Na2CO3 to 100 ml of water in order to achieve a ratio of 0.5 between
concentrations of [CO3
2-
] and [Al3+
] ions. Following preparation of solutions, carbonate
solution was introduced into a jacketed beaker and the metal solution was mixed dropwise
using a micro-pump whilst carefully controlling the rate of relative addition in order to
maintain the pH at 8.5 using NaOH, such that it favours homogeneous precipitation of
metals into brucite-like layers. Specific quantities of Ni(NO3)2.6H2O, Al(NO3)2.9H2O and
Na2CO3 for NiAlCO3- HTlc formulation with different Ni/Al molar ratios are given in Table 2.8.
After completion of precipitation, slurry was aged for 18 hours at 60 °C under vigorous
stirring. The precipitate was then filtered under vacuum filtration and washed to eliminate

13
alkali metals and nitrate ions. Filtrate was then left overnight and dried at ambient
temperature under light air flow within a fume cupboard. X-ray diffraction analysis was then
conducted to confirm formation of the desired HTlcs. Final particulate NiAlCO3- HTlcs are
highlighted in Figure 2.1.
2.3.2 XRD of Hydrotalcite Catalysts
Evaluation of atomic arrangement of mineral crystals in the respective formulated
hydrotalcites was conducted using X-ray diffraction analysis with a Brucker D2 X-ray
diffractometer with a Co (Cobalt) source, radiation (λ = 0.174 nm), and Ni (Nickel) filter in
order to obtain Powder X-ray Diffraction (PXRD) patterns. The analysis was carried out at a
scan speed of 15 minutes with a step size of 0.370 over a 2Theta range of 10 – 100°. The
samples were previously crushed manually with the scope of generating a homogenous
particle size across samples such that consistent and accurate readings can be attained by
the diffractometer. Analysis of Powder X-ray Diffraction (PXRD) patterns were carried out
using a Brucker S8 TIGER XRF to confirm elemental composition and relative molar ratios of
cations. A schematic of the X-ray diffractometer utilised is highlighted in Figure 2.2.

14
Mean crystallite size was evaluated by implementing the Scherer equation (Abate et al.,
2016):
Where:
K – Shape factor
λ – Wavelength of X-ray beam
β – Width (FWHM) of the (0 0 3) diffraction line
θ – Bragg’s diffraction angle
2.4 Experimental Procedure for Upgrading Experiments
The upgrading experiments were executed in a batch autoclave reactor. The schematic
diagram of the experimental setup is shown in Figure 2.3.

15
0.36 g of particulate catalyst was placed in 18 g of heavy oil in the batch autoclave reactor
(100ml) and agitated via a two blade impeller. The reactor was purged with nitrogen to
remove air and pressurised to 20 bar. Upgrading reaction was effectuated at optimised
reaction temperature of 425 °C and stirring speed of 500 rpm. Upgrading reaction was
allowed to reach 100 °C before turning on the agitator at stirring speed of 500 rpm; detail
experimental conditions are highlighted in Table 2.9. Zero time was accounted for when
internal temperature reached 425 °C as it is to be understood that reaction time initiates
when heavy oil and reactants present in the reactor reach operating conditions.
Representations of duplicate heating curves upgrading experiments for each sample are
given in Appendix A.

16
A reaction time of 10 minutes was effectuated at operating conditions and once
elapsed, heating was stopped and reactor was allowed to be cooled to room temperature.
Upgrading reaction experiments were also carried out without catalyst as control in order to
investigate effect of dispersed catalyst.
2.5 Analytical Instruments
2.5.1 Density and API Gravity Measurement
Density and API (American Petroleum Institute) gravity of feed and produced oils,
which determines how heavy or light a crude oil is compared to water, was evaluated using a
digital Anton Paar DMA 35 portable density meter (Anton Paar GmbH, Austria) at 15 °C and
reported in g.cm-3
. The methodology behind the Anton DMA 35 portable density meter is
through introduction of crude oil into the U-shaped glass tube via a pump lever. Agitation of
filled U-shaped tube allows obtaining of density measurement based on oscillation of U-tube.
Oil temperature is measured via a temperature sensor at the measuring cell. Fig.2.4.

17
represents the digital Anton Paar DMA 35 portable density meter utilised for density and API
gravity measurement. Equations 2.2 and 2.3 allow calculation of API gravity and change in
API gravity.
Where:
SG – Specific Gravity
Specific calculations of API gravity and Change in API gravity are given in Appendix B.
2.5.2 Viscosity Measurement
Oil viscosity evaluation determines its internal resistance to flow. Viscosity of feed
and upgraded oils were evaluated using a Bohlin CVO 50 NF rheometer (Malvern
Instruments Ltd, United Kingdom). Figure 2.5 highlights the schematic of the viscometer and
parallel geometry of an aluminium plate with diameter 40mm and polished surface. Prior to

18
carrying out viscosity measurements, rheological behaviour of oil with a parallel plate gap
size set at 100 µm is measured and this is achieved through a viscometry mode which
evaluates viscosity of crude oil as a function of shear stress against shear rate.
Newtonian fluid behaviour was highlighted in the before and after upgrading reaction
samples thus conforming correlation of oil viscosity with increasing shear rate at a range of
0.5 to 600s-1
, henceforth indicating that viscosity of crude oil is independent of shear rate.
Consequently, viscosity measurements were conducted at a shear rate of 100 s-1
and 25 ±
0.1 °C. The data obtained were averages of duplicate measurements, each of which
attained from five data points. Equation 2.4 is used to calculate degree of viscosity reduction
(DVR).
Where:
µo – Viscosity of THAI feed oil (Pa.s)
µ - Viscosity of upgraded oil (Pa.s)

19
Evaluation of respective viscosities and degree of viscosity reductions are given in Appendix
C.
2.5.3 Asphaltene Content Measurement
Asphaltenes are the heaviest component of heavy crude oil, separated by
precipitation of diluted heavy oil with straight chain alkanes such as n-heptane or n-hexane.
Maltene (mixture of saturates, aromatics and resins) is the residual fraction. In this study,
asphaltene was precipitated from THAI feed oils and produced upgraded oils using n-
Hexane in accordance to ASTM D2007-80.
1 g of oil samples was mixed with 35 mL of n-C6H14, which was used as a precipitant.
Oil and n-C6H14 mixture were agitated for 2 hours using a magnetic stirrer and left for 24
hours to allow precipitation and settlement of asphaltenes. The precipitated portion was
vacuum filtered via a Whatman 1 filter paper to separate the n-C6H14 soluble fraction from
the asphaltene portion. n-C6H14 was utilised to wash the filtered asphaltenes until a
colourless liquid was detected from filter. Filter paper and precipitate were dried for an
additional 2 hours in order to remove any residual n-C6H14 and subsequent precipitated
asphaltenes were weighed. Equation 2.5 was utilised to calculate weight percentage of the
asphaltenes content.
Specific calculations of asphaltene content present in each sample is provided in Appendix
D.
2.5.4 True Boiling Point (TBP) Distribution
Simulated distillation (SIMDIS) based on an Agilent 6850N gas chromatography (GC)
and calibrated in agreement with ASTM-D2887-08 offers a broad TBP distribution range of
carbon numbers of petroleum and its distillates, thus it was utilised for characterization of

20
feed and produced oils. A schematic of the Agilent 6850N gas chromatography is highlighted
in Figure 2.6.
A Programmed Temperature Vaporisation (PTV) injector is implemented whereby rapid
heating of sample to 355 °C allows sample to be vaporised before being introduced into the
GC, thus reducing impact of large volume sample that causes overload in the column and
detector. Prior to injection, feed and produced oil samples were diluted with carbon
disulphide (CS2) in a ratio of 1 to 5. CS2 was selected as the dilution solvent due to its
characteristic properties for the GC, which include crude oil miscibility, low boiling point (BP)
and low response factor in the Flame Ionization Detector (FID). Following preparation of the
blend, 1 µL of dilution was taken through a syringe and injected into the GC; each run was
executed in duplicate. The operating parameters of the FID were 260 °C, air flow at 450
mL.min-1
, hydrogen flow at 40 mL.min-1
and nitrogen flow at 32.3 mL.min-1
. A helium flow at
20 mL.min-1
was utilised to elute the column and subsequent analyses at a column
temperature of 20 °C.min-1
from 40 to 260 °C were conducted. Calibration of GC was
effectuated using a standard hydrocarbon mixture comprising C5 – C40. Method of analysis is
obtained via conversion of high-boiling point or high molecular weight fractions to lighter
fractions (BP < 343 °C). Conversion is described as the conversion of the 343 C°+

21
hydrocarbons present in feed oil to the produced upgraded oils as defined by the thermal
and catalytic cracking expression:
Distillables comprise light and medium oil fractions in the produced oil. Henceforth,
calculation of the conversion is achieved through quantification of weight of BP greater than
343 °C hydrocarbons found in feed oil and liquid products, then calculating conversion via
(Ortiz-Moreno et al., 2012):
The expressed conversion only takes into consideration materials that elute the GC column.
2.5.5 Thermogravimetric Analysis (TGA)
In order to determine quantity of coke deposit on spent catalysts, a thermogravimetric
analyser (TGA) was utilised. TGA was effectuated with NETZSCH - Geratebau GmbH, TG
209 F1 Iris®
as shown in Figure 2.7. 20 – 22 mg of spent catalyst sample was recuperated
from the reactor and placed on a platinum crucible with lid top above the microbalance.
Platinum was utilised to avoid issues in regard to corrosion and coke formation at high
temperatures. The micro-furnace programmed conditions are: ramp temperature in range of
25 – 900 °C and heating rate of 10 °C.min-1
with air flow rate of 50 mL.min-1
. Mass change of
the sample in percent (wt. %) as a result of burn-off occurring through temperature rise was
recorded by the TG 209 F1 Iris®
which runs under Proteus®
software.

22
Principles of electromagnetic power compensation are applied in the vacuum-tight thermo-
microbalance as highlighted in Figure 2.8. Sample is heated by a micro-furnace bounded by
a cooling jacket and loss of sample weight as a result of burn-off on heating and air
exposure is determined by the TGA sensitive microbalance.

23
3. Results and Discussion
3.1 Characterisation of Hydrotalcites via X-ray Powder Diffraction
In order to determine whether NiAlCO3-HTlcs were successfully formulated, X-ray
diffraction analysis was conducted to evaluate atomic arrangement of the mineral crystals in
the formulated 2:1, 3:1 and 4:1 NiAlCO3-HTlcs. Powder X-ray diffraction patterns obtained
from the X-ray diffractometer are highlighted in Figure 3.1.
From Figure 3.1., it can be observed that NiAlCO3-HTlc samples exhibit
characteristics that commonly feature in layered structures. XRD patterns of NiAlCO3-HTlc
catalysts highlight several diffraction peaks at 2θ = 12.7°, 26.1°, 40.3°, 45.5°, 53.8°, 71.5°,
72.9°, 77.2° and 85.6°. The emphasized peaks are narrow, symmetric and intense
reflections of the basal (003), (006) and (012) planes at low 2θ angles and broader, small
and at higher angles for the nonbasal (015) and (018) planes. The two reflections of (110)
and (113) can be clearly distinguished at 2θ = 72°. Diffraction peaks of NiAlCO3-HTlc

24
catalysts observed fall in line with similar diffraction peak patterns reported by Touahra et al.
(2015) at 2θ = 11.61°, 23.30°, 35.20°, 39.55°, 47.07°, 61.24°, 62.63° and 66.40° indexed at
planes (003), (006), (012), (015), (018), (110), (113) and (116) that correspond to the layered
double hydroxides structure Takovite [JCPDS file 15-0087]. It can be observed that some
variation is highlighted in 2θ angles obtained in the current study in contrast to the ones
reported in literature, however the same diffraction peaks that characterise hydrotalcite-like
behaviour are featured. In addition, although XRD patterns for 4:1 NiAlCO3-HTlc displayed
hydrotalcite-like phase, an impurity phase at 2θ = 75.8° was also observed, which highlights
that lower values of x were obtained for Ni(OH)2. Sharpness and intensity of XRD peaks is
proportional to crystallinity of LDHs that is hydrotalcites with highly ordered structures, as
reported by Guil-López et al. (2012) and Bolognini et al. (2003). Furthermore, it can be
observed from Figure 3.1 that peak intensity of NiAlCO3-HTlc catalysts decreases with
increasing Ni/Al ratio, which may be attributed to the presence of lower aluminium content,
subsequently causing a disordered LDH layer and disorder in LDH structure.
In addition, findings provided by Cantrell et al. (2005) and Wang et al. (2007),
allowed evaluation of lattice parameters c = 3d0 0 3 and a = 2d1 1 0 using Bragg’s Law.
Moreover, an average crystallite size of each NiAlCO3-HTlcs was determined using equation
2.1, the Scherrer equation, on the (003) plane. Detailed calculations of lattice parameter and
unit cell dimension are given in Appendix E. Corresponding lattice parameters of diffraction
peaks observed in Figure 3.1 at index 003 and 110 are presented in Table 3.1 and Table
3.2.

25
The average interlayer distance c, corresponds to three times the interlayer distance,
and dependent on size/orientation of interlayer anions and electrostatic forces occurring
between the latter and the layers, while the crystallographic parameter a, is defined as the
average cation – cation distance (Abate et al., 2016). The latter is most pivotal for
hydrotalcites and it can be highlighted from Table 3.2 that the crystallographic parameter
increases with increasing catalyst concentration, explained by the size of Al3+
ion being

26
smaller than Ni2+
, henceforth with increasing Ni2+
ions, cation – cation distance increases as
a result of increasing repulsion between Ni2+
and Al3+
cations.
3.2 Effect of Diverse Ni/Al Molar Ratios on Upgraded Oil Mass Balance
The reaction process converts heavy oil into light oil thus gases are released and
coke is deposited on the bed. Henceforth, mass of gas liberated was evaluated by
subtracting masses of produced liquid and solid deposits formed in the reactor following the
reaction process from a known mass of heavy oil feed. Mass balances of the three products
gas, coke and liquid were evaluated as a percentage of the mass of the feed oil using
equations 3.1 and 3.2:
Where:
Wi = Weight of component
WFeed = Weight of THAI feed oil
A more detailed calculation of the mass balance is given in Appendix F.
The gas, coke and liquid yields evaluated through equations 3.1 and 3.2 are highlighted in
Table 3.3. It can be observed that increment in catalyst concentration from the thermal
reaction, where no NiAlCO3-HTlc is present, up to the 4:1 NiAlCO3-HTlc catalyst, favours
production of gases and coke, while less liquid products are produced as catalyst
concentration increases, suggesting a low degree of catalytic upgrading. Although Table 3.3
highlights an inconsistency in the yield of coke and liquid produced for the 3:1 Ni/Al ratio
HTlc, a trendline was observed when individual charts of gas, coke and liquid yield (wt. %) of
samples were plotted as shown in Figure 3.2, 3.3 and 3.4, thus conforming the trends
stipulated. The amount of coke produced for 2:1 Ni/Al ratio was 30.6 wt. % increasing to 32.0

27
wt. % in the 4:1 Ni/Al ratio, and liquid yields were 55.1 decreasing to 32.4 wt. % respectively.
The yield of gases was 14.3 wt. % for 2:1 Ni/Al ratio increasing to 35.6 wt. % in 4:1 Ni/Al
ratio.
0
5
10
15
20
25
30
35
40
Thermal Ni/Al ratio
2:1
Ni/Al ratio
3:1
Ni/Al ratio
4:1
Yield(wt.%)
Samples
Gas (wt. %)
Linear (Trendline)

28
A similar mass balance was described by Shah et al. (2011), they reported that gas,
coke and liquid yields were 1.72, 2.08 and 96.21% from upgrading using CoMo catalyst at
425 °C. It can be observed that the relative yields reported by Shah et al. (2011) show a
drastic difference in comparison to the yields attained in the current study. The difference in
relative yields obtained can be attributed to the fact that CoMo is an oil-soluble dispersed
catalyst that displays highly dispersive characteristics in heavy oil, high surface area/volume
ratio and conversion to metal sulphides during in situ reactions, which are regarded as active
species in the upgrading of heavy oil (Jeon et al., 2011). Furthermore, transplant of
0
5
10
15
20
25
30
35
Thermal Ni/Al ratio
2:1
Ni/Al ratio
3:1
Ni/Al ratio
4:1
Yield(wt.%)
Samples
Coke (wt. %)
Linear (Trendline)
0
10
20
30
40
50
60
70
80
Thermal Ni/Al ratio
2:1
Ni/Al ratio
3:1
Ni/Al ratio
4:1
Yield(wt.%)
Samples
Liquid (wt. %)
Linear (Trendline)

29
inexpensive promoters, such as nickel, have been attempted for the purpose of decreasing
cost of catalyst and enhance hydrocracking activity, however previous studies have
highlighted that dispersed catalysts composed of multiple metal substances were simple
physical mixtures of different monometallic precursors (Jeon et al., 2011). High yields of gas
and coke obtained at 425 °C in the NiAlCO3-HTlc upgrading processes can be explained
due to a higher catalytic cracking reaction at high temperature, as well as coke and gas
representing to be end products of the process, thus expected to display greater yield at high
temperature.
3.3 Effect of Diverse Ni/Al Molar Ratios of Hydrotalcites on API Gravity and Viscosity
In order to evaluate the amount of distillate accessible from the oil, analysis of crude
oil API gravity is pivotal. In Table 3.4, API gravity of feedstock, thermal and respective
NiAlCO3-HTlc catalyst with Ni/Al molar ratio 2:1, 3:1 and 4:1 oil are presented. It is clear that
API gravity significantly increases for thermal and NiAlCO3-HTlc catalysts in comparison to
feed oil. API gravity for oil produced via thermal and NiAlCO3-HTlcs at ratio 2:1, 3:1 and 4:1
catalytic upgrading was 21.4, 20.3, 21.2 and 17.2 °API respectively. Furthermore, Figure 3.5
highlights a comparison in the degree of change in API gravity between thermal oil and
NiAlCO3-HTlc oils against feedstock oil. The greatest change in API gravity was observed for
the thermal upgrading of 6.6 °API and closely matched by the 3:1 Ni/Al ratio NiAlCO3-HTlc of
6.4 °API. Although a 6.4 °API was obtained for 3:1 Ni/Al ratio NiAlCO3-HTlc, this data does
not follow the general trend observed in Figure 3.5, as it is highlighted that as concentration
of catalyst increases, degree of change in API decreases, thus stipulation for an ambiguity in
the results obtained for the 3:1 NiAlCO3-HTlc catalyst. Regardless, it is clear that catalyst
activity decreased with increasing Ni/Al ratio concentration as observed in Figure 3.5,
however some measurable improvement is shown with the lowest change in API being 2.4
°API for the 4:1 Ni/Al ratio NiAlCO3-HTlc. Increase in API gravity as observed from Table 3.4
and change in API presented in Figure 3.5 shows improved quality of produced oil. Greaves
et al. (2000) reported that a 5.9 °API increase requires only a 15% of diluent to meet pipeline

30
transportation specifications in comparison to 30-50% needed for non-upgraded bitumen
produced from SAGD and CSS processes, thus highlighting the fact that the 2:1 NiAlCO3-
HTlc closely matches the 5.9 °API increase that meets pipeline transportation specifications
with an °API increase of 5.5, henceforth it can be stipulated that the 2:1 NiAlCO3-HTlc is the
best performing catalyst in respect to this data.

31
Heavy oils portray high viscosity henceforth hindering their extraction and pipeline
transportation to refineries. Viscosities of feedstock, thermal and respective NiAlCO3-HTlc
catalyst with Ni/Al molar ratio 2:1, 3:1 and 4:1 oils are presented in Table 3.4. It can be
highlighted that there is a substantial viscosity reduction of the upgraded oil samples in
contrast to feed oil, with a higher viscosity reduction (DVR) noticed for the 2:1 NiAlCO3-HTlc
evaluated from Equation 2.4 in Section 2.5.2. Viscosity reduced from 0.811 Pa.s (Feed oil) to
0.012 Pa.s (Thermal), 0.004 Pa.s (2:1 NiAlCO3-HTlc), 0.003 Pa.s (3:1 NiAlCO3-HTlc) and
0.007 Pa.s (4:1 NiAlCO3-HTlc) respectively. Additionally, from Figure 3.6 it can be
understood that degree of viscosity reduction decreases from 99.484% to 99.099% with
increasing catalyst concentration. Although an inconsistency in the viscosity reduction in
regard to the 3:1 NiAlCO3-HTlc sample is observed, a similar trend is noted for the change in
API gravity presented in Figure 3.5, which corresponds to the mirror trend of viscosity
decrease with increasing catalyst concentration shown in Figure 3.6, thus further highlighting
the inconsistent data observed for the 3:1 NiAlCO3-HTlc sample from the mass balance.
0
1
2
3
4
5
6
7
8
Thermal Ni/Al ratio 2:1 Ni/Al ratio 3:1 Ni/Al ratio 4:1
ChangeinAPI(°)
Samples
Change in API (°)
Linear (Trendline)

32
Relative decrease in DVR with increasing catalyst concentration can be attributed to
the synergistic effect of the nickel metal that could be higher in the 4:1 NiAlCO3-HTlc due to
presence of more nickel ions in the structure. Cavani et al. (1991) reports that in the scenario
of the brucite, Mg(OH)2 , octahedral of Mg2+
share edges that form stacked infinite sheets
held together by hydrogen bonding. When Mg2+
ions are substituted by a trivalent ion, in this
instance Al3+
, a positive charge is generated in the hydroxyl sheet that is counteracted by
CO3
2-
anions present in the interlayer region between the two brucite-like sheets. Based on
this reaction mechanism, it is understood that HTlc structures are dependent upon the
nature of brucite-like sheet, positions of anions and type of stacking of brucite-like sheets
which may vary with type and quantity of metal present in the HTlc structure.
The maximum viscosity for pipeline transport of crude oil should be less than 0.2
Pa.s (Ancheyta, 2013) and viscosities of produced oils obtained for reactions carried out with
NiAlCO3-HTlcs match this criteria, thus improvement in oil fluidity and quality during recovery
is achievable through this DVR. Moreover, low viscosity oil holds a high API gravity, however
no correlation between API gravity and viscosity can be deduced from the obtained
experimental data as a result of varying factors that affect viscosity and API gravity
differently (Ancheyta, 2013).
98.6
98.7
98.8
98.9
99
99.1
99.2
99.3
99.4
99.5
99.6
99.7
Ni/Al ratio
2:1
Ni/Al ratio
3:1
Ni/Al ratio
4:1
DegreeofViscosityReduction(DVR)
(%)
Samples
Degree of Viscosity Reduction (DVR) (%)
Linear (Trendline)

33
3.4 Effect of Diverse Ni/Al Molar Ratios of Hydrotalcites on TBP Distribution
The low amount of fuel distillates and great residue fraction produced by heavy oil
distillation proves its undesirability for the growing demand in low – boiling distillates
(Jarullah et al., 2011). SIMDIS of feedstock and upgraded oils was categorised into the
distillates: gasoline (IBP to 200 °C), middle distillates (200 – 343 °C) and residual fraction
(BP > 343 °C).TBP distribution curves of feed and produced oils at different NiAlCO3-HTlc
catalysts concentration is provided in Figure 3.7. It can be observed that as NiAlCO3-HTlc
concentration increases from 2:1 to 4:1 in the upgrading experiments, a substantial shift in
TBP curves towards lighter distillate fractions with low – boiling temperatures in comparison
to feed oil occurs. Section 3.3 established that increasing concentration of NiAlCO3-HTlc
catalyst from 2:1 to 4:1 decreases API gravity and DVR. It is therefore evident that upgraded
oils that feature high API gravity and low viscosity values also display highest yields of
distillates. In addition, from Figure 3.7, a drastic shift in the boiling temperature of 53 °C is
observed at 10 vol. % yield for the 2:1 NiAlCO3-HTlc catalyst in comparison to feed oil. This
shift rises to 5, 23, 38, 54 and 87 °C as the cumulative distilled increased from 30 to 90 vol.
% for 2:1 NiAlCO3-HTlc at upgrading temperature of 425 °C. Similar trends can be noted for
the 3:1 and 4:1 NiAlCO3-HTlc as well. The observed shift towards lower distillable
temperatures suggest that produced oils comprise of lower molecular weight components in
comparison to feed oil.
Based on Figure 3.7, an alternative chart representing yields of distillate fractions for
feedstock, thermal and catalytic upgraded oils with different Ni/Al ratio of NiAlCO3-HTlc
catalyst is shown in Figure 3.8.

34
From Figure 3.8, it can be observed that, decrease in yield of light distillates produced by
catalytic upgrading of NiAlCO3-HTlcs with increasing Ni/Al concentration agrees with
decrease in API gravity and increase in viscosity with increasing concentration of produced
oils relative to feed oil highlighted in Figures 3.5 and 3.6. As catalyst concentration increases
from 2:1 to 4:1, conversion of heavy end fractions into lighter distillates decreased with the
lowest conversion attained for the 4:1 NiAlCO3-HTlc catalyst, thus it is clear that catalyst
performance decreases with increasing concentration. The observed trend is expected as
decrease in yield of distillates with boiling point less than 343 °C reduces viscosity of
produced oils (Ancheyta et al., 2005). It is clear that gasoline fractions increased from 22 vol
% in the feedstock oil to 38, 44, 32 and 31 vol. % for the produced oils from thermal cracking
and catalytic upgrading with NiAlCO3-HTlcs at Ni/Al ratio 2:1. 3:1 and 4:1 respectively.
Regardless of decrease in gasoline fractions with increasing catalyst concentration, 2:1
NiAlCO3-HTlc catalyst produces more gasoline fractions in comparison to oil produced from
0
10
20
30
40
50
60
70
80
90
Feed oil Thermal Ni/Al ratio 2:1Ni/Al ratio 3:1Ni/Al ratio 4:1
Amountdistilled(vol.%)
Samples
True - boiling point distribution of feed, thermal and
catalytic upgrading of heavy oil
Gasoline (IBP to 200 °C)
Middle distillates (200 - 343 °C)
Residual fraction (BP > 343 °C)

35
thermal cracking as well. The explanation behind this behaviour lies in the early transfer of
heavy molecules to the micro – particulates active sites, henceforth the reduced particles
size improves reaction rate, contact and hydroconversion, leading to an increase in the yield
of light distillates (Noguera et al., 2012). Figure 3.8 clearly highlights that improved oil quality
was achieved in the 2:1 NiAlCO3-HTlc, magnitude of coke produced was much higher than
the other samples, henceforth suggesting improved catalytic cracking, however this should
not be overlooked as coke is attributed to catalyst deactivation.

36
0
20
40
60
80
100
120
0 100 200 300 400 500 600
Amountdistilled(vol.%)
Temperature (°C)
TBP distribution curves of feedstock oil and produced thermal and NiAl-HTlc catalysts oil
Feed Oil
Thermal
2:1 NiAl-HTlc
3:1 NiAl-HTlc
4:1 NiAl-HTlc

37
3.5 Effect of Diverse Ni/Al Molar Ratios of Hydrotalcites on Spent Catalyst Coke
Content
One of the by-products of upgrading reactions is coke, which becomes adsorbed on
the catalysts’ acid sites. It constitutes of non-volatile components, high molecular weight ply-
aromatic species and attributed to catalyst deactivation by fouling and poisoning active sites
and/or plugging of catalyst pores (Wang and Manos, 2007). Initiation of coke burn-off was
determined via thermogravimetric analysis (TGA) of coke deposit obtained as a result of
thermal and NiAlCO3-HTlc catalytic upgrading reactions. The TGA and DTG (differential
thermogravimetric) of the coke deposit obtained from the previously mentioned reactions are
presented in Figure 3.9. It can be observed that coke is completely burned off at a
temperature of 600 – 620 °C in between all the samples analysed, which agrees with
previous findings obtained by Trejo et al. (2010) and Douda et al. (2004). The respective
studies reported end of decomposition processes of Maya heavy crude oil at 620 °C, thus
proving to be consistent with the signal range emphasised in the DTG curves highlighted in
Figure 3.9. Additionally, Figure 3.9 presents the TGA thermograms or weight loss curves as
a function of ramp temperature for the thermal and spent NiAlCO3-HTlc recovered catalysts
after the upgrading experiments. Increase in ramp temperature allows understanding of
various chemical changes occurring during burn-off and isothermal temperature of 900 °C
guarantees complete burn off of all carbon species during the heating period. It is to be
noted that at temperatures above 620 °C, the deposits present on spent catalysts are
classified as coke as a result of the high energy requirement to achieve coke burn-off.
The derivative weight loss curve (DTG) highlighted in Figure 3.9 allows
comprehension of the different stages during heating period. Several stages can be
identified on the weight loss process; the region from 20 - 210 °C denotes loss as a result of
light oil de-volatilisation, 210 – 625 °C denotes burn – off of macromolecules, for example
asphaltenes and resins and + 625 °C represents coke. Deactivation and shortening of
catalyst lifespan are achieved due to accumulation of coke on the catalyst bed (Ali et al.,

38
2006) however coke deposits on catalysts have been labelled as indication of catalytic
cracking (Krumm et al., 2012). Coke content of spent NiAlCO3-HTlcs decreased in the order
33.2, 25.1 and 24.4 wt. % at Ni/Al ratios 2:1, 3:1 and 4:1 respectively, whilst a coke content
of 28.5 wt. % was obtained for the thermal upgrading with oil alone. Specific coke wt. %
values are presented from thermograms obtained by the NETZSCH-Geratebau GmbH, TG
209 F1 Iris®
given in Appendix G. It can be noted that coke content of spent NiAlCO3-HTlc
catalysts was higher in the 2:1 NiAlCO3-HTlc sample and progressively decreased with
increasing catalyst concentration due to decrease in acid sites strength. In regard to this
phenomenon, Oh et al. (2017) reports that acid strength of Ni/SBA -15 and Ni/Al-SBA-15
catalysts affected HDO of bio-oil as a result of their proton-donating ability. NH3-TPD
measurements highlighted that peaks produced at temperatures above 400 °C correspond
to the desorption of NH3 from strong Brönsted and Lewis sites, while low temperature peaks
are attributed to desorption of NH3 at weak acid sites or formation of NH4+
groups. A strong
acid site improves catalytic activity however high coke formation and deactivation also incurs
(Leyva et al., 2007).
The product distribution obtained in the TGA thermograms highlight an increase in
light naphtha, 8.37 wt. % to 19.6 wt. % and middle distillate fraction, 12.7 wt. % to 26.8 wt. %
while coke yield decreased from 33.2 wt. % to 24.4 wt. % with increasing NiAlCO3-HTlc
catalyst concentration. The observed trends are explained by the control of the rate of free
radical propagation via β-scission induced by active metals, such as nickel, whereby
hydrogen is incorporated into the cracked active hydrocarbon fragments during heavy oil
upgrading (Weitkamp, 2012; Pereux et al., 2010). The relative decrease in coke yield fall in
line with findings obtained by Zhang et al. (2007), who reported that coke yield is significantly
inhibited using dispersed catalysts at 425 °C.

39
-3
-2.5
-2
-1.5
-1
-0.5
0
0.5
0
20
40
60
80
100
120
0 100 200 300 400 500 600 700 800 900
Derivateweightloss(%/°C)
Weightloss(wt.%)
Temperature (°C)
TGA and DTG of spent NiAl-HTlc catalysts
TGA - 2:1 NiAl-HTlc
TGA - 3:1 NiAl-HTlc
TGA - 4:1 NiAl-HTlc
TGA - Thermal
DTG - 2:1 NiAl-HTlc
DTG - 3:1 NiAl-HTlc
DTG - 4:1 NiAl-HTlc
DTG - Thermal

40
3.6 Effect of Diverse Ni/Al Molar Ratios of Hydrotalcites on Asphaltenes content
High viscosity, high density and low API gravity observed in heavy oil is due to the
amount of asphaltenes present within it (Gallaraga et al., 2012). Asphaltene content of feed,
thermally cracked and catalytically upgraded oils with the use of NiAlCO3-HTlc catalysts at
Ni/Al ratios 2:1, 3:1 and 4:1 are presented in Figure 3.10. It is observed that asphaltene
content was reduced from 14 wt. % in feed oil to 7, 6, 5 and 6 wt. % for the thermally
cracked and catalytically upgraded oils of NiAlCO3-HTlc catalysts at Ni/Al ratios 2:1, 3:1 and
4:1 respectively, which suggests that conversion of heaviest fractions to lighter fractions
such as coke, gases and maltene was achieved. Shah et al. (2011) reports that this
behaviour is attributed to catalyst deactivation reactions when the alumina supported
catalysts CoMo, NiMo and ZnO/Cuo were used. It is described that smaller naphthenic or
aromatic ring structures condense into larger multiring aromatic structures that condense as
coke on the catalyst surface. The reactions in question are the chain – reaction formation of
poly – nuclear aromatics and polymerization and cyclization of olefins. This theory explains
the decrease in asphaltenes in the produced oils as it is implied that the catalyst retains or
filters the coke.
Notably, asphaltene content of the oils produced by NiAlCO3-HTlc catalysts proved to
be lower than the produced oil from thermal cracking alone, thus suggesting that catalytic
upgrading is more efficient than thermal cracking. However, difference in asphaltene content
between thermal cracking and catalytic cracking with NiAlCO3-HTlc catalysts is only of about
1%, which can be attributed to the deviation in data as a result of only two runs being
effectuated for each upgrading experiments. The higher asphaltene content highlighted in
the 2:1 NiAlCO3-HTlc as opposed to the 3:1 and 4:1 catalysts confirm the same observation
presented in the true boiling point distribution curves highlighted in Figure 3.7, whereby a
decrease in yield of middle distillates fraction (asphaltenes and resins) with increasing
catalyst concentration is noted. Based on this observation, it is noteworthy to mention that a

41
lower asphaltene content was expected with the 4:1 NiAlCO3-HTlc. Deviation of this data
may be attributed to the insufficient runs conducted as a result of time limiting factors.
4. Conclusion and Recommendations
In order to alleviate increasing global energy demand, petroleum industries and
researches are continuously investigating in new ways to extract deposits of heavy oil and
bitumen. The THAI – CAPRI process entails subsurface catalytic upgrading process in situ
with the scope of heavy oil extraction and light oil conversion that meets refinery feedstock
qualities. The current surface upgrading facilities utilised in industry require extensive capital
investment for upgrader operation, and energy – intensive thus releasing vast quantities of
greenhouse gases. Compared to these upgrading facilities, THAI – CAPRI provides less
energy intensive operation due to in situ combustion to drive catalysis, decreases
environmental impact by leaving impurities such as heavy metals and sulphur in the
reservoir and reduces capital cost by producing upgraded oils with enhanced flow
characteristics (Hashemi et al., 2013).
0
2
4
6
8
10
12
14
16
Feed oil Thermal Ni/Al ratio
2:1
Ni/Al ratio
3:1
Ni/Al ratio
4:1
Asphaltenecontent(wt.%)
Samples
Asphaltene content (wt. %)
Asphaltene content

42
The aim of this study was to upgrade partially upgraded oil provided by Touchstone
Exploration Inc, Saskatchewan, Canada via the THAI – CAPRI process using different molar
concentration of formulated NiAlCO3-HTlc catalysts from 14 °API gravity to an API gravity of
17 – 21 °API, reduce viscosity to improve flow for pipeline transportation and lessen content
of asphaltenes. Thermal cracking and catalytic upgrading experiments were conducted in a
batch autoclave reactor to replicate the THAI – CAPRI process. The impact of several
NiAlCO3-HTlc catalysts at different molar concentrations on API gravity, viscosity, true –
boiling point distribution, coke formation and asphaltenes materialization was investigated.
Based on the aims and objectives set for this study, successful synthesis of NiAlCO3-
HTlc with different Ni/Al concentrations through a co-precipitation method at low
supersaturation conditions was achieved. XRD analysis highlighted hydrotalcite formation
through manifestation of peaks at 2θ = 12.7°, 26.1°, 40.3°, 45.5°, 53.8°, 71.5°, 72.9°, 77.2°
and 85.6°. In regard to improvement in API gravity and viscosity, it was identified that the
upgrading process increased API gravity by 2 – 6 °API points and 99.1 – 99.5% reduction in
viscosity using NiAlCO3-HTlcs thus suggesting high oil recovery that meets pipeline flow
transportation. It was reported that API gravity decreased (20.3 to 17.2 °API) and viscosity
increased (0.004 to 0.007 Pa.s) with increasing catalyst concentration, thus suggesting that
catalyst activity decreased with increasing catalyst concentration. The reasoning behind the
observed trends is postulated to lie in the synergistic effect of nickel metal that is expected to
be higher in the 4:1 NiAlCO3-HTlc due to the presence of more nickel ions in the structure.
Key limitations in the current study include the insufficient time to execute the upgrading
experiments as it was noted that deviations in trends occurred for the 3:1 NiAlCO3-HTlc
sample, henceforth in future work, several more thermal cracking and catalytic upgrading
experimental runs are advised to be effectuated in order to alleviate error deviations, achieve
consistency in the obtained data and confirm whether the stipulation of catalyst activity
decreasing with increasing catalyst concentration in NiAlCO3-HTlcs is sustainable.
NiAlCO3-HTlc catalysts displayed high yields of distillates following the upgrading
process, thus suggesting that produced oils contain lower molecular weight components in

43
comparison to feed oil and highlighting effectiveness in catalytic upgrading. Coke is also
another parameter that reflects performance of upgrading process, the current study
highlighted a decrease in coke content with increasing NiAlCO3-HTlc catalyst concentration
from 33.2 wt. % to 24.4 wt. %. Relative content of coke is proportional to the level of catalytic
cracking, thus it was highlighted that the 2:1 NiAlCO3-HTlc is the most efficient in regards to
upgrading, however accumulation of coke promotes catalyst deactivation, henceforth future
studies should incorporate hydrogen as the reaction media to control catalyst deactivation,
because it is able to moderate addition reactions of macromolecules radicals that leads to
coke formation unlike nitrogen (Hart et al., 2014).
Moreover, the study focused on the interpretation in performance of catalytic
upgrading with increasing concentration of NiAlCO3-HTlcs, which highlighted a decrease in
catalytic cracking with increasing concentration. In light of the observations made, although
2:1 NiAlCO3-HTlc catalyst proves to be better in certain aspects of upgrading, differences
between catalytic upgrading and thermal cracking is negligible, henceforth upgrading via 2:1
NiAlCO3-HTlc catalyst proves to less economical as it provides similar results to thermal
cracking alone. Based on these economic factors, upgrading analysis with synthetic NiMo-
HTlcs is strongly recommended, as it has been observed that the industrially used HDS
NiMo catalyst displays high level of upgrading in terms of viscosity reduction and API gravity
increase, thus incorporation of molybdenum in a hydrotalcite structure may enhance level of
upgrading in comparison to NiAlCO3-HTlcs (Shah et al., 2013).
This report has attempted to provide an understanding in regard to the enhancement
of heavy oil upgrading using alternative synthetic catalysts, namely NiAlCO3-HTlc anionic
clays, to produce light conventional oils that meets refinery specifications. Issues concerning
catalyst deactivation in previous studies prevents complete efficiency of upgrading process,
thus the proposed technologies highlight the extent of upgrading enhancement that is
achieved whilst reducing the environmental impact associated with the process.

44
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46
Jeon, S., Na, J., Ko, C., Yi, K., Rho, N. and Park, S. (2011). Preparation and Application of an Oil-
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48
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49
Appendix A
Upgrading Process of Thermal Cracking and Catalytic Upgrading
A.1 Thermal cracking with oil alone
Figure A.1. Heating curves of duplicate thermal cracking experiments with oil alone
A.2 Catalytic upgrading with 2:1 NiAlCO3-HTlc
Figure A.2. Heating curves of duplicate catalytic upgrading experiments with 2:1 NiAlCO3-HTlc
0
10
20
30
40
50
60
70
80
0
50
100
150
200
250
300
350
400
450
500
0 100 200 300 400 Pressure(barg)
Temperature(°C)
Time (min)
Upgraging Experiment - Thermal
Temperature - 1st run
Temperature - 2nd run
Pressure - 1st run
Pressure - 2nd run
0
10
20
30
40
50
60
70
80
0
50
100
150
200
250
300
350
400
450
500
0 50 100 150 200 250 300 350
Pressure(barg)
Temperature(°C)
Time (min)
Upgrading Experiment - 2:1 NiAlCO3-HTlc
Pressure - 1st run
Pressure - 2nd run

50
0
10
20
30
40
50
60
70
80
0
50
100
150
200
250
300
350
400
450
500
0 50 100 150 200 250 300 350
Pressure(barg)
Temperature(°C)
Time (min)
Pressure - 1st run
Pressure - 2nd run
0
10
20
30
40
50
60
70
80
0
50
100
150
200
250
300
350
400
450
500
0 50 100 150 200 250 300 350
Pressure(barg)
Tempreature(°C)
Time (min)
Pressure - 1st run
Pressure - 2nd run

51
Appendix B
Calculation of API Gravity and Change in API Gravity
The following equations are utilised to calculate API gravity and change in API gravity:
𝐴𝑃𝐼 =
141.5
𝜌
− 131.5
Where:
ρ – Specific Gravity
𝐶ℎ𝑎𝑛𝑔𝑒 𝑖𝑛 𝐴𝑃𝐼 𝑔𝑟𝑎𝑣𝑖𝑡𝑦 (°) = 𝐴𝑃𝐼 𝑜𝑓 𝑝𝑟𝑜𝑑𝑢𝑐𝑒𝑑 𝑜𝑖𝑙 − 𝐴𝑃𝐼 𝑜𝑓 𝑓𝑒𝑒𝑑𝑠𝑡𝑜𝑐𝑘
B.1 Calculation of Feed Oil API Gravity
𝜌 = 0.967 𝑔 𝑐𝑚−3
𝐴𝑃𝐼 =
141.5
0.967
− 131.5
= 14.8°
B.2 Calculation of API Gravity and Change in API Gravity for Thermal Oil alone
First run: ρ = 0.927 g cm-3
𝐴𝑃𝐼 =
141.5
0.927
− 131.5
= 21.1°
Second run: ρ = 0.9244 g cm-3
𝐴𝑃𝐼 =
141.5
0.9244
− 131.5
= 21.6°
Average API: (21.1 + 21.6) / 2 = 21.4°
Change in API: 21.4° - 14.8° = 6.6°

52
B.3 Calculation of API Gravity and Change in API Gravity for Catalytic Upgraded oil
with 2:1 NiAlCO3-HTlc
𝐴𝑃𝐼 =
141.5
0.9346
− 131.5
= 19.9°
𝐴𝑃𝐼 =
141.5
0.9299
− 131.5
= 20.7°
Average API: (19.9° + 20.7°) / 2 = 20.3°
Change in API: 20.3° - 14.8 ° = 5.5
B.4 Calculation of API Gravity and Change in API Gravity for Catalytic Upgraded Oil
𝐴𝑃𝐼 =
141.5
0.9217
− 131.5
= 22.0°
𝐴𝑃𝐼 =
141.5
0.9309
− 131.5
= 20.5°
Average API: (22.0° + 20.5°) / 2 = 21.2°
Change in API: 21.2° - 14.8° = 6.4°

53
B.5 Calculation of API Gravity and Change in API Gravity for Catalytic Upgraded Oil
𝐴𝑃𝐼 =
141.5
0.9537
− 131.5
= 16.9°
𝐴𝑃𝐼 =
141.5
0.9503
− 131.5
= 17.4°
Average API: (17.4° + 16.9°) / 2 = 17.2°
Change in API: 17.2°- 14.8° = 2.4°

54
Appendix C
Calculation of Viscosity and Degree of Viscosity Reduction (DVR)
Calculation of viscosity obtained by taking the average viscosity between 5 points during a
60 seconds operation time for each experimental run. Final average viscosity calculated by
taking the average between the averages produced by the duplicate measurements. Degree
of Viscosity Reduction (DVR) evaluated using:
𝐷𝑉𝑅(%) =
(𝜇 𝑜 − 𝜇)
𝜇 𝑜
× 100
Where:
µo – Viscosity of THAI feed oil (Pa.s)
µ - Viscosity of upgraded oil (Pa.s)
C.1 Calculation of Feed Oil Viscosity
Table C.1. Relative viscosity measurements obtained at five points for Feed oil; Time of operation (60
seconds); Temperature (25 °C).
Average Feed Oil Viscosity =
0.8064+0.8107+0.8139+0.813+0.8122
5
= 0.81124 𝑃𝑎. 𝑠
Feed oil
Points Time
(s)
Temperature
(°C)
Shear
Stress
(Pa)
Shear Rate
(1/s)
Viscosity
(Pa.s)
Target
Shear Rate
(1/s)
1 10.07 25 803.4 996.3 0.8064 1000
2 21.46 25 809.8 998.9 0.8107 1000
3 32.88 25 813.1 999 0.8139 1000
4 44.27 25 812.7 999.7 0.813 1000
5 55.9 25 811.4 999 0.8122 1000

55
C.2 Calculation of Viscosity and Degree of Viscosity Reduction (DVR) for Thermal Oil
alone
Table C.2. Relative viscosity measurements obtained at five points for Thermal Upgrading Experiment
(1st run); Time of operation (60 seconds); Temperature (25 °C)
Average Thermal Viscosity (1st
run) =
0.01351+0.01345+0.01338+0.01332+0.01324
5
= 0.01338 𝑃𝑎. 𝑠
Thermal Degree of Viscosity Reduction (DVR) (1st
run) =
0.81124−0.01338
0.81124
= 98.35067 %
Table C.3. Relative viscosity measurements obtained at five points for Thermal Upgrading Experiment
(2nd run); Time of operation (60 seconds); Temperature (25 °C)
Upgrading Experiment – Thermal (1st
run)
Points Time
(s)
Temperature
(°C)
Shear
Stress
(Pa)
Shear Rate
(1/s)
Viscosity
(Pa.s)
Target
Shear Rate
(1/s)
1 10.05 25 13.48 997.7 0.01351 1000
2 21.45 25 13.38 995 0.01345 1000
3 32.83 25 13.38 999.7 0.01338 1000
4 44.23 25.1 13.32 999.8 0.01332 1000
5 55.65 25 13.23 999.4 0.01324 1000
Upgrading Experiment – Thermal (2nd
run)
Points Time
(s)
Temperature
(°C)
Shear
Stress
(Pa)
Shear Rate
(1/s)
Viscosity
(Pa.s)
Target
Shear Rate
(1/s)
1 10.15 25 10.01 992.9 0.01009 1000
2 21.55 24.9 10.09 999.2 0.0101 1000
3 32.96 24.9 10.13 999.2 0.01014 1000
4 44.35 25 10.06 999.5 0.01007 1000
5 55.75 25.1 10.09 999.6 0.01009 1000

56
Average Thermal Viscosity (2nd
run) =
0.01009+0.0101+0.01014+0.01007+0.01009
5
= 0.010098 𝑃𝑎. 𝑠
Thermal Degree of Viscosity Reduction (DVR) (2nd
run) =
0.81124−0.010098
0.81124
= 98.75524 %
Average Thermal Viscosity between duplicate measurements = 0.011739 Pa. s
Average Thermal Degree of Viscosity Reduction (DVR) = 98.552955 %
C.3 Calculation of Viscosity and Degree of Viscosity Reduction (DVR) for Catalytic
Upgraded oil with 2:1 NiAlCO3-HTlc
Table C.3. Relative viscosity measurements obtained at five points for 2:1 NiAlCO3-HTlc Upgrading
Experiment (1st run); Time of operation (60 seconds); Temperature (25 °C)
Average 2:1 NiAlCO3-HTlc Viscosity (1st
run) =
0.003401+0.003238+0.0032+0.003209+0.003365
5
= 0.003283 𝑃𝑎. 𝑠
2:1 NiAlCO3-HTlc Degree of Viscosity Reduction (DVR) (1st
run) =
0.81124−0.003283
0.81124
= 99.59536 %
Upgrading Experiment – 2:1 NiAlCO3-HTlc (1st
run)
Points Time
(s)
Temperature
(°C)
Shear
Stress
(Pa)
Shear Rate
(1/s)
Viscosity
(Pa.s)
Target
Shear Rate
(1/s)
1 10.32 25 3.356 986.8 0.003401 1000
2 21.72 25 3.235 999.1 0.003238 1000
3 33.1 25 3.197 999 0.0032 1000
4 44.5 25 3.205 999 0.003209 1000
5 55.91 25 3.339 992.3 0.003365 1000

57
Experiment (2nd run); Time of operation (60 seconds); Temperature (25 °C)
Average 2:1 NiAlCO3-HTlc Viscosity (2nd
run) =
0.004733+0.004964+0.005118+0.005229+0.005392
5
= 0.005087 𝑃𝑎. 𝑠
2:1 NiAlCO3-HTlc Degree of Viscosity Reduction (DVR) (2nd
run) =
0.81124−0.005087
0.81124
= 99.12142 %
Average 2:1 NiAlCO3-HTlc Viscosity between duplicate measurements = 0.004185 Pa. s
Average 2:1 NiAlCO3-HTlc Degree of Viscosity Reduction (DVR) = 99.48414 %
Upgrading Experiment – 2:1 NiAlCO3-HTlc (2nd
run)
Points Time
(s)
Temperature
(°C)
Shear
Stress
(Pa)
Shear Rate
(1/s)
Viscosity
(Pa.s)
Target
Shear Rate
(1/s)
1 10.24 25 4.611 974.2 0.004733 1000
2 21.65 25 4.935 994.2 0.004964 1000
3 33.03 25 5.133 1003 0.005118 1000
4 44.43 25 5.242 1002 0.005229 1000
5 55.83 25 5.393 1000 0.005392 1000

58
Experiment (1st run); Time of operation (60 seconds); Temperature (25 °C)
run) =
0.004751+0.00433+0.003975+0.003929+0.004217
5
= 0.00424 𝑃𝑎. 𝑠
run) =
0.81124−0.00424
0.81124
= 99.47729 %
Experiment (2nd run); Time of operation (60 seconds); Temperature (25 °C)
run)
Points Time
(s)
Temperature
(°C)
Shear
Stress
(Pa)
Shear Rate
(1/s)
Viscosity
(Pa.s)
Target
Shear Rate
(1/s)
1 10.2 25 4.705 990.3 0.004751 1000
2 21.6 25 4.354 1005 0.00433 1000
3 33 25 3.95 993.9 0.003975 1000
4 44.39 25.1 3.931 1001 0.003929 1000
5 55.78 25 4.124 977.9 0.004217 1000
Upgrading Experiment – 3:1 NiAlCO3-HTlc (2nd
run)
Points Time
(s)
Temperature
(°C)
Shear
Stress
(Pa)
Shear Rate
(1/s)
Viscosity
(Pa.s)
Target
Shear Rate
(1/s)
1 10.25 25 3.667 985.9 0.00372 1000
2 21.65 25 3.711 1004 0.003696 1000
3 33.05 25 3.535 1001 0.003533 1000
4 44.43 25 3.459 999.5 0.003461 1000
5 55.83 25 3.428 999.6 0.003429 1000

59
Average 3:1 NiAlCO3-HTlc Viscosity (2nd
run) =
0.00372+0.003696+0.003533+0.003461+0.003429
5
= 0.003568 𝑃𝑎. 𝑠
3:1 NiAlCO3-HTlc Degree of Viscosity Reduction (DVR) (2nd
run) =
0.81124−0.003568
0.81124
= 99.5602 %
Average 3:1 NiAlCO3-HTlc Viscosity between duplicate measurements = 0.003904 Pa. s
Average 3:1 NiAlCO3-HTlc Degree of Viscosity Reduction (DVR) = 99.51875 %
Only one set of viscosity measurement for the 4:1 NiAlCO3-HTlc due to insufficient sample
quantity for the Bohlin CVO 50 NF rheometer.
Experiment (1st run); Time of operation (60 seconds); Temperature (25 °C).
run) =
0.008131+0.008607+0.007499+0.005915+0.005485
5
= 0.007127 𝑃𝑎. 𝑠
run) =
0.81124−0.007127
0.81124
= 98.86206 %
run)
Points Time
(s)
Temperature
(°C)
Shear
Stress
(Pa)
Shear
Rate (1/s)
Viscosity
(Pa.s)
Target
Shear
Rate
(1/s)
1 10.32 25 8.39 1032 0.008131 1000
2 21.7 25 8.469 983.9 0.008607 1000
3 33.1 25 7.665 1022 0.007499 1000
4 44.5 25 7.238 1224 0.005915 1000
5 55.9 25 5.476 998.4 0.005485 1000

60
Appendix D
Calculation of Asphaltene Content
Weight percentage of asphaltenes content calculated using:
𝑤𝑡. % 𝐴𝑠𝑝ℎ𝑎𝑙𝑡𝑒𝑛𝑒 𝑐𝑜𝑛𝑡𝑒𝑛𝑡 =
𝑊𝑒𝑖𝑔ℎ𝑡 𝑜𝑓 𝑝𝑟𝑒𝑐𝑖𝑝𝑖𝑡𝑎𝑡𝑒𝑑 𝑎𝑠𝑝ℎ𝑎𝑙𝑡𝑒𝑛𝑒 (𝑔)
𝑊𝑒𝑖𝑔ℎ𝑡 𝑜𝑓 ℎ𝑒𝑎𝑣𝑦 𝑜𝑖𝑙 (𝑔)
× 100
D.1 Calculation of Asphaltene Content in Feed Oil
Mass of oil = 1.00 𝑔
Volume of hexane = 35 𝑚𝑙
Hexane added (ml) = 12 𝑚𝑙
Weight of both filter papers = 0.58 𝑔
Weight of both filter papers and oil = 0.72 𝑔
Weight of precipitated asphaltene = 0.72 − 0.58 = 0.14 𝑔
wt.% Asphaltene content =
0.14
1
× 100 = 14 %
D.2 Calculation of Asphaltene Content in Thermal Oil alone
0.07
1
× 100 = 7 %
D.3 Calculation of Asphaltene Content in Catalytic Upgraded Oil with 2:1 NiAlCO3-HTlc
0.06
1
× 100 = 6 %

61
0.05
1
× 100 = 5 %
0.06
1
× 100 = 6 %

62
Appendix E
Calculation of Lattice Parameter, Average Crystallite Size and Unit Cell
Dimension
E.1 Calculation of Lattice Parameter, c and Average Crystallite Size, Å
Calculation of the lattice parameter, c and average crystallite size, Å achieved by analysing
(003) plane. Since X-ray diffraction peaks given as a function of 2θ, θ evaluated for each
NiAlCO3-HTlcs. Respective values given in Table E.1.
Table E.1. Relative values of θ for each respective NiAlCO3-HTlcs in (003) plane
Sample 2θ θ
2:1 NiAlCO3-HTlc 13 6.5
3:1 NiAlCO3-HTlc 12.75 6.375
4:1 NiAlCO3-HTlc 12.5 6.25
Following evaluation of θ, sin θ evaluated, therefore:
2:1 NiAlCO3-HTlc } sin 6.5 = 0.1132
3:1 NiAlCO3-HTlc } sin 6.375 = 0.111
4:1 NiAlCO3-HTlc } sin 6.25 = 0.1089
Following evaluation of sin θ, d0 0 3 evaluated via (Bialas et al., 2016):
𝜆
2 × sin 𝜃
Where:
λ = Wavelength of X-ray beam (0.174 nm)
Therefore:
d0 0 3 2:1 NiAlCO3-HTlc } 0.768551237 nm
d0 0 3 3:1 NiAlCO3-HTlc } 0.783783784 nm
d0 0 3 4:1 NiAlCO3-HTlc } 0.798898072 nm

63
Converting nm into ångström, therefore:
d0 0 3 2:1 NiAlCO3-HTlc } 0.768551237 x 10 = 7.68551237 Å
d0 0 3 3:1 NiAlCO3-HTlc } 0.783783784 x 10 = 7.83783784 Å
d0 0 3 4:1 NiAlCO3-HTlc } 0.798898072 x 10 = 7.98898072 Å
Lattice parameter, c described as (Bialas et al., 2016):
𝑑0 0 3 × 3
Therefore:
c, 2:1 NiAlCO3-HTlc } 23.057 Å
Prior to calculation of Average crystallite size, angle evaluated in radiance using:
22 × 𝛽
7 × 180
Where:
β = Width of (0 0 3) diffraction line
β in respective NiAlCO3-HTlcs are:
2:1 NiAlCO3-HTlc } β = 1.9
Therefore, angles in radiance:
2:1 NiAlCO3-HTlc } 0.033174603 rad
3:1 NiAlCO3-HTlc } 0.038412698 rad
4:1 NiAlCO3-HTlc } 0.043650794 rad

64
Following calculation of angles in radiance, average crystallite size evaluated through
Scherer equation (Millange et al., 2010):
𝐷 =
𝐾 × 𝜆
𝛽 × cos(𝜃)
Where:
K – Shape factor (0.9)
λ – Wavelength of X-ray beam (0.174 nm)
β – Width (FWHM) of the (0 0 3) diffraction line
θ – Bragg’s diffraction angle
Therefore, average crystallite size for respective NiAlCO3-HTlcs:
2:1 NiAlCO3-HTlc } 53.230 Å
E.2 Calculation of Unit Cell Dimension, a
Calculation of the lattice parameter, a achieved by analysing (110) plane. Since X-ray
diffraction peaks given as a function of 2θ, θ evaluated for each NiAlCO3-HTlcs. Respective
values given in Table E.2.
Table E.2. Relative values of θ for each respective NiAlCO3-HTlcs in (110) plane
Sample 2θ θ
2:1 NiAlCO3-HTlc 72.3 36.125
3:1 NiAlCO3-HTlc 72 36
4:1 NiAlCO3-HTlc 71 35.625
Following evaluation of θ, sin θ evaluated, therefore:
2:1 NiAlCO3-HTlc } sin 36.125 = 0.5895
3:1 NiAlCO3-HTlc } sin 36 = 0.5879
4:1 NiAlCO3-HTlc } sin 35.625 = 0.5825

65
Following evaluation of sin θ, d1 1 0 evaluated via (Bialas et al., 2016):
𝜆
2 × sin 𝜃
Where:
λ = Wavelength of X-ray beam (0.174 nm)
Therefore:
d1 1 0 2:1 NiAlCO3-HTlc } 0.147583 nm
d1 1 0 3:1 NiAlCO3-HTlc } 0.147984 nm
d1 1 0 4:1 NiAlCO3-HTlc } 0.149356 nm
Converting nm into ångström, therefore:
D1 1 0 2:1 NiAlCO3-HTlc } 0.147583 x 10 = 1.476 Å
D1 1 0 3:1 NiAlCO3-HTlc } 0.147984 x 10 = 1.479 Å
D1 1 0 4:1 NiAlCO3-HTlc } 0.149356 x 10 = 1.494 Å
Unit cell dimension, a described as (Bialas et al., 2016):
𝑑1 1 0 × 2
Therefore:
a, 2:1 NiAlCO3-HTlc } 2.952 Å

66
Appendix F
Mass Balance Calculations
F.1 Calculation of Mass Balance for Thermal Oil alone
F.1.1 First Run
Mass of sleeve = 205.37 g
Mass of oil = 18.0 g
Total mass = 223.37 g (Before reaction)
Mass of tissue = 14.90 g Mass of tissue with oil = 15.33 g
Mass of filter paper = 1.28 g Mass of filter paper with oil = 1.48 g
Oil on tissue = 15.33 – 14.90 = 0.43 g
Oil on filter paper = 1.48 – 1.28 = 0.20 g
Mass of sleeve and oil (After reaction) = 220.48 g
Mass of sleeve and oil (After 24 hrs) = 208.70 g
Total mass of sleeve and oil (After reaction) = 220.48 + 0.43 + 0.20 = 221.11 g
Mass of gas = 223.37 – 221.11 = 2.26 g
Mass % gas = 2.26/18 x 100 = 12.6%
Mass of deposit = (208.70 + 0.2) – 205.37 = 3.53 g
Mass % deposit = 3.53/18 x 100 = 19.6%
Mass % liquid = 100 – 12.6 – 19.6 = 67.8%

67
F.1.2 Second Run
Oil on tissue = 6.56 – 5.24 = 1.32 g
Oil on filter paper =1.50 – 1.31 = 0.19 g
Mass of gas = 223.37 – 220.79 = 2.58 g
Mass % gas = 2.58/18.01 x 100 = 14.3%
Mass of deposit = (208.58 + 0.2) – 205.36 = 3.42 g
Mass % deposit = 3.42/18.01 x 100 = 19.0%
Mass % liquid = 100 – 14.3 – 19.0 = 66.7%

68
F.2 Calculation of Mass Balance for Catalytic Upgraded Oil with 2:1 NiAlCO3-HTlc
F.2.1 First Run
Mass of Ni/Al (2:1) catalyst = 0.36 g
Oil on tissue = 9.27 – 8.23 = 1.04 g
Mass of gas = 223.72 – 222.11 = 1.61 g
Mass % gas = 1.61/18 x 100 = 8.9%
Mass of deposit = (211.98 + 0.2) – 205.36 = 6.82 g
Mass % deposit = 6.82/18 x 100 = 37.9%
Mass % liquid = 100 – 8.9 – 37.9 = 53.2%

69
F.2.2 Second Run
Oil on tissue = 6.82 – 5.94 = 0.88 g
Mass of gas = 223.72 – 220.18 = 3.54 g
Mass % gas = 3.54/18 x 100 = 19.6%
Mass of deposit = (209.34 + 0.2) – 205.36 = 4.18 g
Mass % deposit = 4.18/18 x 100 =23.2%
Mass % liquid = 100 – 19.6 – 23.2 = 57.2%

70
F.3.1 First Run
Oil on tissue = 4.40 – 3.42 = 0.98 g
Mass of gas = 223.72 – 220.26 = 3.46 g
Mass % gas = 3.46/18.01 x 100 = 19.2%
Mass of deposit = (209.69 + 0.2) – 205.35 = 4.54 g
Mass % deposit = 4.54/18.01 x 100 = 25.2%
Mass % liquid = 100 – 19.2 – 25.2 = 55.6%

71
F.3.2 Second Run
Oil on tissue = 3.77 – 3.44 = 0.33 g
Mass of gas = 223.74 – 220.47 = 3.27 g
Mass % gas = 3.27/18.01 x 100 = 18.2%
Mass of deposit = (208.60 + 0.2) – 205.38 = 3.42 g
Mass % deposit = 3.42/18.01 x 100 = 19.0%
Mass % liquid = 100 – 18.2 – 19 = 62.8 %

72
F.4.1 First Run
Oil on tissue = 4.54 – 3.75 = 0.79 g
Mass of gas = 223.72 – 214.90 = 8.82 g
Mass % gas = 8.82/18 x 100 = 49%
Mass of deposit = (212.84 + 0.2) – 205.36 = 7.68 g
Mass % deposit = 7.68/18 x 100 = 42.7
Mass % liquid = 100 – 49.0 – 42.7 = 8.3%

73
F.4.2 Second Run
Oil on tissue = 3.82 – 2.92 = 0.90 g
Mass of gas = 224.01 – 220.0 = 4.01 g
Mass % gas = 4.01/17.99 x 100 = 22.3%
Mass of deposit = (209.28 + 0.2) – 205.66 = 3.82 g
Mass % deposit = 3.82/17.99 x 100 = 21.2%
Mass % liquid = 100 – 22.3 – 21.2 = 56.5%

74
The respective gas, coke and liquid fractions obtained through each experiment tabulated in
Table F.1.
Table F.1. Gas, coke and liquid yields obtained from duplicate measurements
Sample
Upgrading Experiment – 1st
run Upgrading Experiment – 2nd
run
Gas
(wt. %)
Coke
(wt. %)
Liquid
(wt. %)
Gas
(wt. %)
Coke
(wt. %)
Liquid
(wt. %)
Thermal 12.6 19.6 67.8 14.3 19.0 66.7
2:1 NiAlCO3-HTlc 8.9 37.9 53.2 19.7 23.2 57.1
3:1 NiAlCO3-HTlc 19.2 25.2 55.6 18.2 19.0 62.8
4:1 NiAlCO3-HTlc 49.0 42.7 8.3 22.3 21.2 56.5

75
Appendix G
Thermogravimetric Graphs
G.1 Thermogravimetric Analysis of Thermal Oil alone
Figure G.1. Specific TGA and DTG curves of thermal oil obtained from TG 209 F1 Iris® software

76
G.2 Thermogravimetric Analysis of Spent 2:1 NiAlCO3-HTlc
Figure G.2. Specific TGA and DTG curves of spent 2:1 NiAlCO3-HTlc obtained from TG 209 F1 Iris® software

77

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