viii
TABLE OF CONTENTS
CHAPTER
TITLE
PAGE
TITLE
DECLARATION
ii
DEDICATION
iii
ACKNOWLEDGEMENT
iv
PREFACE
v
ABSTRACT
vi
ABSTRAK
vii
TABLE OF CONTENT
viiii
LIST OF TABLES
ix
LIST OF FIGURES
xii
LIST OF SYMBOLS AND ABBREVIATIONS
xv
LIST OF APPENDICES
1
2
xviii
INTRODUCTION
1.1 Research Background and Problem Statement
1
1.2 Objectives of Research
4
1.3 Research Strategies
4
1.4 Scope of the Research
4
LITERATURE REVIEW
2.1 The Importance of Solid Catalyst
6
2.2 Solid catalysts - Introduction to M41S family
7
ix
2.3 Generation of Active Sites in AlMCM-41
Mesoporous Materials
3
10
2.4 Generation of acid sites via sulphation
12
2.5 Friedel-Crafts Reactions and Solid Catalysts
14
EXPERIMENTAL
3.1 Starting Materials
15
3.2 Preparation of AlMCM-41
15
3.3 Preparation of Protonated MCM-41
16
(H-AlMCM-41)
3.4 Synthesis of Sulphated AlMCM-41
17
3.5 Characterization of MCM-41 Materials
17
3.5.1 X-ray Powder Diffraction (XRD)
17
3.5.2 Fourier Transform Infrared Spectroscopy
(FTIR)
18
3.5.3 Solid State Magic Angle Spinning
Nuclear Magnetic Resonance (MAS
NMR) Spectroscopy
19
3.5.4 Thermogravimetric and Differential
Thermal Analysis (TG-DTA)
21
3.5.5 Nitrogen Adsorption-Desorption
Isotherm Analysis
22
3.5.6 Fourier Transform Infrared
Spectroscopy of Pyridine Adsorption
3.5.7 Hammett Acidity Analysis
3.6 Dibenzoylation of Biphenyl Reaction over
23
26
26
Sulphated AlMCM-41
3.6.1 Dibenzoylation of Biphenyl Reaction
over Various Types of Catalysts
28
3.6.2 Synthesis of 4-PBP as authentic sample
28
3.6.3 Synthesis of 4, 4’-DBBP as authentic
Sample
29
x
3.6.4 Calibration Curve for Authentic Sample
4
29
RESULTS AND DISCUSSION
4.1 X-Ray Diffraction Analysis
32
4.2 Infrared Spectroscopy of AlMCM-41
Molecular Sieves
36
4.3 Nitrogen Adsorption Measurement
38
4.4 Thermal Analysis
40
27
4.5 Solid State Al MAS NMR
29
43
4.6 Solid State Si MAS NMR
47
4.7 Acidity Measurements
49
4.7.1 Pyridine-FTIR Spectroscopy
49
4.7.2 Hammett indication Analysis
53
4.8 Catalytic testing: Dibenzoylation of
Biphenyl
55
4.8.1 Effect of Catalyst
55
4.8.2 Effect of SiO2/Al2O3 ratio
58
4.8.3 Reaction Temperature
59
4.8.4 Effect of Catalyst Loading
60
4.8.5 Effect of Benzoyl Chloride : Biphenyl
Mole Ratio
4.9 Mechanism
62
63
4.10 Mass balance of Dibenzoylation of Biphenyl
with Benzoyl Chloride
4.11 Proposed Structure
5
66
68
CONCLUSIONS
5.1 Conclusions
69
REFERENCES
71
APPENDICES
77
xi
LIST OF TABLES
NO. TABLE
TITLE
PAGES
2.1
Comparison of the various phases of catalysts.
7
3.1
Amount of NaAlO2 added in preparing AlMCM-41.
16
3.2
The organic compounds used as Hammett Indicators.
26
3.3
GC-FID oven-programmed setup for identifying 4, 4’-DBBP.
27
3.4
GC-MSD oven-programmed setup for identifying 4, 4’-DBBP.
28
4.1
XRD data of various MCM-41 samples.
33
4.2
The textural properties of various protonated and sulphated
39
MCM-41 samples obtained form calculation and surface
analyzer.
4.3
Peak areas of octahedral aluminium (Aloct) and tetrahedral
45
aluminium (Altet) from 27Al MAS NMR spectra
4.4
Peak areas of octahedral aluminium species in aluminium
45
sulphate (AlAl2(SO4)3) and sulphated AlMCM-41 (AlSulphated
AlMCM-41)
from 27Al MAS NMR spectra.
4.5
Peak areas of silicon species in SCAL-4
48
4.6
Pyridine FTIR data of protonated and sulphated MCM-41
52
materials.
4.7
The results of acid strength of catalysts using Hammett
54
indicators.
4.8
Benzoylation and dibenzoylation of biphenyl with benzoyl
57
chloride over various types of catalysts at 180 oC for 24 h.
4.9
Amount of Brönsted acid active sites in SCAL-4 with different
61
loading and and its effect towards conversion of biphenyl.
4.10
Theoretical mass balance
67
4.11
Experimental mass balance
67
xii
LIST OF FIGURES
NO. FIGURE
1.1
TITLE
Two proposed reaction routes: (Route1) direct and (Route 2)
PAGES
3
consecutive synthesis of the dibenzoylation of biphenyl using
sulphated AlMCM-41 mesoporous materials and benzoyl chloride.
1.2
Flow diagram of research strategies.
5
2.1
Illustration of hexagonal honeycomb structure of mesoporous
9
MCM-41 with 2 nm to 10 nm pore size.
2.2
Formation of MCM-41 materials. (a) Coagulation of surfactants
9
process, (b) Combination of organic and inorganic materials, (c)
MCM-41.
2.3
Framework of (a) SiMCM-41 and (b) AlMCM-41.
10
2.4
Generation of Brönsted acid sites.
11
2.5
Generation of Lewis acid sites.
12
2.6
Benzoylation of an aromatic compound using aluminium
13
trichloride as catalyst, leading to a stable Lewis complex.
2.7
Friedel-Crafts acylation showing a typical starting materials,
14
products and waste mass balance.
3.1
Range of 29Si chemical shifts of Qn in solid silicate.
21
3.2
Proposed mechanism of interaction between pyridine molecules
24
with (a) Brönsted and (b) Lewis acid sites in MCM-41 molecular
sieves.
3.3
Adsorption and desorption of pyridine apparatus for acidity study.
25
3.4
Quantitative calibration plot of biphenyl.
30
3.5
Quantitative calibration plot of 4-PBP.
30
3.6
Quantitative calibration plot of 4, 4’-DBBP.
31
xiii
4.1
X-ray diffractogram patterns of uncalcined mesoporous MCM-41
34
molecular sieves. (a) UNCAL-1, (b) UNCAL-2, (c) UNCAL-3
and (d) UNCAL-4.
4.2
X-ray diffractogram patterns of mesoporous MCM-41 materials
34
after calcinations at 550 oC for 10 h. (a) CAL-1, (b) CAL-2, (c)
CAL-3 and (d) CAL-4.
4.3
X-ray diffractogram patterns of protonated MCM-41 materials
35
o
after ion exchange with NH4NO3 and calcination at 500 C (a)
HCAL-1, (b) HCAL-2, (c) HCAL-3 and (d) HCAL-4.
4.4
X-ray diffractogram patterns of sulphated MCM-41 materials (a)
35
SCAL-1, (b) SCAL-2, (c) SCAL-3 and (d) SCAL-4.
4.5
FTIR spectra of uncalcined mesoporous MCM-41 molecular
37
sieves.
4.6
FTIR spectra of calcined mesoporous MCM-41 molecular sieves.
37
4.7
FTIR spectra of sulphated mesoporous MCM-41 molecular sieves.
38
4.8
Modification of surface of MCM-41 through sulphation leads to
39
shrinkage of pore diameter.
4.9
Thermogravimetric analysis of uncalcined MCM-41 sample
40
(UNCAL-2) in nitrogen gas with 20 oC/min heating rate.
4.10
Thermogravimetric analysis of uncalcined MCM-41 samples with
41
various ratio of SiO2/Al2O3.
4.11
Thermograms of a series of protonated MCM-41 molecular sieves.
42
4.12
Thermogravimetric curves of sulphated AlMCM-41 materials.
43
4.13
27
44
Al NMR spectra of protonated MCM-41 molecular sieves (a)
HCAL-4, (b) HCAL-3, (c) HCAL-2 and (d) HCAL-1.
4.14
27
Al NMR spectra of sulphated MCM-41 molecular sieves (a)
44
SCAL-4, (b) SCAL-3, (c) SCAL-2 and (d) SCAL-1.
4.15
29
Si NMR spectrum of sulphated MCM-41 molecular sieves
48
(SCAL-4).
4.16
The possible silicon species and Brönsted acid sites in sulphated
49
AlMCM-41.
4.17
The pyridine-FTIR spectra of purely siliceous sulphated MCM-41
(SCAL-1) at (a) room temperature, (b) 150 oC, (c) 250 oC and (d)
50
xiv
350 oC.
4.18
The pyridine-FTIR spectra of sulphated AlMCM-41 (SCAL-2) at
o
o
51
o
(a) room temperature, (b) 150 C, (c) 250 C and (d) 350 C .
4.19
The pyridine-FTIR spectra of sulphated AlMCM-41 (SCAL-3) at
51
(a) room temperature, (b) 150 oC, (c) 250 oC and (d) 350 oC .
4.20
The pyridine-FTIR spectra of sulphated AlMCM-41 (SCAL-4) at
52
(a) room temperature, (b) 150 oC, (c) 250 oC and (d) 350 oC .
4.21
FTIR spectra of silanol groups of MCM-41 materials at 250 oC (a)
53
before treatment (HCAL-1) and (b) after treatment (SCAL-1) of
sulphuric acid.
4.22
Dibenzoylation of biphenyl catalyzed by various types of catalysts
57
4.23
Conversion of biphenyl over various ratio of SiO2/Al2O3 within 24
58
h.
4.24
Yield of 4, 4’-DBBP over various ratio of SiO2/Al2O3 within 24 h.
59
4.25
Temperature effect towards dibenzoylation of biphenyl over
60
SCAL-4.
4.26
Effect of catalyst loading towards dibenzoylation of biphenyl over
61
SCAL-4.
4.27
Effect of Biphenyl : Benzoyl Chloride molar ratio towards
62
dibenzoylation of biphenyl over SCAL-4.
4.28
Mechanism of how the electron density affects BP and 4-PBP in
63
attacking benzoylium ion.
4.29
Formation of 4-phenyl benzophenone (4-PBP) via electrophilic
64
substitution.
4.30
Mechanism of production of 4, 4’-dibenzoyl biphenyl (4, 4’-
65
DBBP).
4.31
Stoichiometrical chemical equation of dibenzoylation of biphenyl
66
reaction.
4.32
Hydrolysis of benzoyl chloride as side reaction in production of
68
benzoic acid and benzoic anhydrice.
4.33
Scheme proposed for the sulphated AlMCM-41 materials showing
possible Brönsted acid sites.
68
xv
LIST OF SYMBOL AND ABBREVIATIONS
MCM-41
-
Mobile Crystalline Material-41
RHA
-
Rice husk ash
Py
-
Pyridine
i.e.
-
Id est (that is)
BET
-
Brunauer-Emmett-Teller
GC
-
Gas chromatography
Å
-
Angstrom (10-10 meters)
kV
-
Kilovolts
α
-
Alpha
β
-
Beta
PDPV
-
Poly (4, 4’-diphenylene diphenylvinylene)
LED
-
Light emitting devices
IUPAC
-
International Union of Pure Applied Chemistry
LCT
-
Liquid-crystal templating
n
-
Diffraction order from n = 1, 2, 3, ….
d
-
Distance
2D
-
Two dimensions
λ
-
Lambda
θ
-
Theta
δ
-
Delta
FTIR
-
Fourier transform infrared
NMR
-
Nuclear magnetic resonance
MAS
-
Magic angle spinning
CP
-
Cross polarization
EFAL
-
Extra-framework aluminium
ppm
-
Part per million
xvi
%
-
Percent
~
-
Approximately
TG/DTA
-
Thermogravimetric and Differential Thermal Analysis
TGA
-
Thermogravimetric Analysis
DTA
-
Differential Thermal Analysis
Ho
-
Hammett acidity function
µL
-
Microlitre
MS
-
Mass spectrometry
GC-MS
-
Gas
chromatography
combined
with
spectrometry
4-PBP
-
4-Phenyl benzophenone
4, 4’-DBBP
-
4, 4’-dibenzoylbiphenyl
CTABr
-
Cetyltrimethylammonium bromide
NH4OH
-
Ammonium hydroxide
min
-
Minute
o
-
Celsius
h
-
Hour
wt%
-
Weight percent
g
-
Gram
mg
-
milligram
SiO2/Al2O3
-
Silica over alumina ratio
mol
-
Mole
mmol
-
Millimole
m.p.
-
Melting point
mA
-
Milliampere
o
-
Degree
cm-1
-
Per centimeter
UNCAL-1
-
Uncalcined MCM-41 with SiO2/Al2O3 ratio ∞
UNCAL-2
-
Uncalcined AlMCM-41 with SiO2/Al2O3 ratio 60
UNCAL-3
-
Uncalcined AlMCM-41 with SiO2/Al2O3 ratio 30
UNCAL-4
-
Uncalcined AlMCM-41 with SiO2/Al2O3 ratio 15
CAL-1
-
Calcined MCM-41 with SiO2/Al2O3 ratio ∞
CAL-2
-
Calcined AlMCM-41 with SiO2/Al2O3 ratio 60
C
mass
xvii
CAL-3
-
Calcined AlMCM-41 with SiO2/Al2O3 ratio 30
CAL-4
-
Calcined AlMCM-41 with SiO2/Al2O3 ratio 15
HCAL-1
-
Protonated MCM-41 with SiO2/Al2O3 ratio ∞
HCAL-2
-
Protonated AlMCM-41 with SiO2/Al2O3 ratio 60
HCAL-3
-
Protonated AlMCM-41 with SiO2/Al2O3 ratio 30
HCAL-4
-
Protonated AlMCM-41 with SiO2/Al2O3 ratio 15
SCAL-1
-
Sulphated MCM-41 with SiO2/Al2O3 ratio ∞
SCAL-2
-
Sulphated AlMCM-41 with SiO2/Al2O3 ratio 60
SCAL-3
-
Sulphated AlMCM-41 with SiO2/Al2O3 ratio 30
SCAL-4
-
Sulphated AlMCM-41 with SiO2/Al2O3 ratio 15
MHz
-
Megahertz
µs
-
Microsecond
TMS
-
Tetramethyl silane
BJH
-
Barrett, Joyner, Halenda
mbar
-
millibar
kPa
-
Kilopascal
m/z
-
Mass over charge
ao
-
Unit cell parameters
t
-
Crystallite size
Wd
-
Pore diameter
bd
-
Pore wall thickness
xviii
LIST OF APPENDICES
APPENDICES
A
TITLE
PAGES
Calculation of the amount of pyridine adsorbed on the sample in
77
the acidity study of sulphated AlMCM-41 samples.
B
Infrared spectrum of 4-phenyl benzophenone (4-PBP).
78
C
Mass spectrum of 4-phenyl benzophenone (4-PBP).
79
D
Infrared spectrum of 4, 4’-dibenzoyl biphenyl (4, 4’-DBBP).
80
E
Mass spectrum of 4, 4’-dibenzoyl biphenyl (4, 4’-DBBP).
81
F
Calculation of % conversion and % selectivity.
82
G
The pyridine-FTIR spectra of HCAL-1 at (a) room temperature,
83
o
o
o
(b) 150 C, (c) 250 C and (d) 350 C.
H
The pyridine-FTIR spectra of HCAL-2 at (a) room temperature,
84
(b) 150 oC, (c) 250 oC and (d) 350 oC.
I
The pyridine-FTIR spectra of HCAL-3 at (a) room temperature,
85
(b) 150 oC, (c) 250 oC and (d) 350 oC.
J
The pyridine-FTIR spectra of HCAL-4 at (a) room temperature,
o
o
86
o
(b) 150 C, (c) 250 C and (d) 350 C.
K
Chromatogram of reactants at 0 h.
87
L
Chromatogram of reactants and products.
88
M
Data obtained from GC-FID Chromatograms (Friedel-Crafts
89
dibenzoylation of biphenyl with benzoyl chloride over SCAL-4).
N
Mass balance of dibenzoylation of biphenyl with benzoyl
90
chloride (Experimental)
O
Mass balance of dibenzoylation of biphenyl with benzoyl
chloride (Theoretical)
98