TABLE OF CONTENT
Title page
Certification
Approval page
Dedication
Acknowledgement
Table of content
List of Tables
Abstract
List of Figures
List of Abbreviations and Symbols
CHAPTER ONE: INTRODUCTION
Research background
1.2 Research objectives and scope
1.3 Significant of study
CHAPTER TWO: LITERATURE REVIEW
Introduction
2.2 Clays
2.2.1 Classification of clays
2.2.2 Modification of clays-
2.2.3 Methods of modification of clay minerals
2.1.3.1 Thermal activation
2.1.3.2 Acid activation
2.1.3.2.1Mechanism of acid activation
2.3 Characterization techniques for clay
2.3.1 X-ray fluorescence
2.3.2 Fourier transform infrared spectroscopy (FTIR)
2.3.3 Powdered X-ray diffraction analysis
2.3.4 Scanning electron microscope
2.4 Use of clay in decolourizing and refining oil
2.4.1 Types of clays used in decolourizing
2.4.2 Properties required of decolourizing clays
2.5 Activated carbon
2.5.1 Production
2.5.2 Physical reactivation
2.5.3 chemical reactivation
2.6 Pre-treatment – Degumming, deodorization and bleaching
2.6.1 Degumming process
2.6.2 Deodorization
2.6.3 Bleaching process
2.7 What is degumming?
2.7.1 Types of degumming
2.7.1.1 Dry degumming
2.7.1.2 Water degumming
2.7.1.3 Acid degumming
2.7.1.4 Enzymatic degumming
2.7.1.5 EDTA – degumming
2.7.1.6 Membrane degumming
2.7.2 Process theory of degumming
2.8 What is bleaching?
2.8.1 Types of bleaching
2.8.1.1 Heat bleaching
2.8.1.2 Chemical oxidation
2.8.1.3 Adsorption
2.8.2 Process theory of bleaching
2.8.3 Palm oil (Elaeis guineensis)
2.8.3.1 Composition of crude palm oil (CPO)
2.9 Survey of related literature
CHAPTER THREE: EXPERIMENTAL
Modification of clay by chemical activation
3.2 Physical and chemical characterization of Nteje clay
3.2.1 Surface area measurement
3.2.2 Bulk density
3.2.3 Specific Gravity
3.2.4 Oil retention
3.2.5 pH and acidity measurement
3.2.6 Cation exchange capacity (CEC)
3.3 Pretreatment – degumming and neutralization
3.3.1 Degumming process
3.3.2 Neutralization process
3.4 Bleaching process
3.5 Adsorption kinetics
3.6 Adsorption isotherm
3.7 Adsorption thermodynamics
CHAPTER FOUR: RESULTS AND DISCUSSION
Physico-chemical characterization of Nteje clay
4.2 FTIR characterisation
4.3 XRD analysis
4.4 Effect of activation
4.5 Effect of bleaching time
4.6 Effect of temperature
4.7 Adsorption kinetics
4.8 Adsorption isotherm
4.9 Adsorption thermodynamics
CHAPTER FIVE:CONCLUSIONS AND RECOMMENDATIONS
5.1 Conclusion
5.2 Recommendations
5.3 Contribution to knowledge
REFERENCES
APPENDICES

APPENDICES
Appendix A: Table of Values for the Amount of Pigment Adsorbed (Percentage Bleaching) and Isotherm Parameters at Various Constant Temperatures.
Appendix B: Table of Values for the Adsorption Thermodynamic Plot at Constant Time.
Appendix C: Table of Values for the Adsorption Kinetic Plots at Constant Temperatures.
Appendix D: Detailed X-ray Diffraction (XRD) Analysis Result as Obtained from Physics Advanced Laboratory, Sheda Science and Technology, Abuja

 
LIST OF FIGURES

Figure 2.1: Flow Diagram of Dry Degumming

Figure 2.2: Flow Diagram of Water Degumming

Figure 2.3: Flow Diagram of Acid Degumming

Figure 2.4: Flow Diagram of EDTA Degumming

Figure 2.5: Chemical Structure of Phosphatide

Figure 2.6: Mechanism of Adsorption

Figure 4.1: FTIR Spectrum Of Natural Nteje Clay

Figure 4.2: FTIR Spectrum Of Activated Nteje Clay

Figure 4.3: Charts of Percentage Bleaching with Time at Various Constant Temperatures

Figure 4.4: Pseudo-second Order Plot for AC, FE and ANC at 10 min

Figure 4.5: Pseudo-second Order Plot for AC, FE and ANC at 20 min

Figure 4.6: Pseudo-second Order Plot for AC, FE and ANC at 30 min

Figure 4.7: Pseudo-second order Plot for AC, FE and ANC at 40 min

Figure 4.8: Pseudo-second Order Plot for AC, FE and ANC at 50 min

Figure 4.9: Elovich Plot for AC, FE and ANC at 10 min

Figure 4.10: Elovich Plot for AC, FE and ANC at 20 min

Figure 4.11: Elovich plot for AC, FE and ANC at 30 min

Figure 4.12: Elovich Plot for AC, FE and ANC at 40 min

Figure 4.13: Elovich Plot for AC, FE and ANC at 50 min

Figure 4.14: Power Function Equation Plot for AC, FE and ANC at 10 min

Figure 4.15: Power Function Equation Plot for AC, FE and ANC at 20 min

Figure 4.16: Power Function Equation Plot for AC, FE and ANC at 30 min

Figure 4.17: Power Function Equation Plot for AC, FE and ANC at 40 min

Figure 4.18: Power Function Equation Plot for AC, FE and ANC at 50 min

Figure 4.19: Freundlich Isotherm Plot for AC, FE and ANC at 10 oC

Figure 4.20: Freundlich Isotherm Plot for AC, FE and ANC at 20 oC

Figure 4.21: Freundlich Isotherm Plot for AC, FE and ANC at 30 oC

Figure 4.22: Freundlich Isotherm Plot for AC, FE and ANC at 40 oC

Figure 4.23: Freundlich Isotherm Plot for AC, FE and ANC at 50 oC

Figure 4.24: Langmuir Isotherm Plot for AC, FE and ANC at 10 oC

Figure 4.25: Langmuir Isotherm Plot for AC, FE and ANC at 20 oC

Figure 4.26: Langmuir Isotherm Plot for AC, FE and ANC at 30 oC

Figure 4.27: Langmuir Isotherm Plot for AC, FE and ANC at 40 oC

Figure 4.28: Langmuir Isotherm Plot for AC, FE and ANC at 50 oC

Figure 4.29: Plot of lnK_f versus 1⁄T for AC, FE and ANC at 10 min

Figure 4.30: Plot of lnK_f versus 1⁄T for AC, FE and ANC at 20 min

Figure 4.31: Plot of lnK_f versus 1⁄T for AC, FE and ANC at 30 min

Figure 4.32: Plot of lnK_f versus 1⁄T for AC, FE and ANC at 40 min

Figure 4.33: Plot of lnK_f versus 1⁄T for AC, FE and ANC at 50 min

LIST OF TABLES

Table 2.1: Compositions of Phospholipids of Palm Oil (mole %)

Table 4.1: Physical Properties of AC, FE, ANC and UANC

Table 4.2: XRD Analysis Result of Nteje Clay

Table 4.3: Effect of Bleaching Time at 60 oC

Table 4.4: Effect of Bleaching Time at 80 oC

Table 4.5: Effect of Bleaching Time at 100 oC

Table 4.6: Effect of Bleaching Time at 120 oC

Table 4.7: Effect of Bleaching Time at 140 oC

Table 4.8: Pseudo-second Order Parameters for AC, FE and ANC

Table 4.9: Elovich Parameters for AC, FE and ANC

Table 4.10: Power Function Equation Parameters for AC, FE and ANC

Tables 4.11: Freundlich and Langmuir Isotherm Parameters evaluated for AC, FE and ANC at 60 oC

Table 4.12: Freundlich and Langmuir Isotherm Parameters evaluated for AC, FE and ANC at 80 oC

Table 4.13: Freundlich and Langmuir Isotherm Parameters evaluated for AC, FE and ANC at 100 oC

Table 4.14: Freundlich and Langmuir Isotherm Parameters evaluated for AC, FE and ANC at 120 oC

Table 4.15: Freundlich and Langmuir Isotherm Parameters evaluated for AC, FE and ANC at 140 oC

Table 4.16: Thermodynamic Parameters Evaluated for AC, FE and ANC at 10 Mins.

Table 4.17: Thermodynamic Parameters Evaluated for AC, FE and ANC at 20 Mins.

Table 4.18: Thermodynamic Parameters Evaluated for AC, FE and ANC at 30 Mins.

Table 4.19: Thermodynamic Parameters Evaluated for AC, FE and ANC at 40 Mins.

Table 4.20: Thermodynamic Parameters Evaluated for AC, FE and ANC at 50 Mins.

CHAPTER ONE

INTRODUCTION

1.1       Research Background

Natural clay minerals are well known and familiar to mankind from the earliest days of civilization¹. Because of their low cost, abundance in most continents of the world, high sorption properties, high dissolubility in acidic solutions and potential for ion exchange, clay materials are suitable substances as source of metals and adsorbents. Clay is composed mainly of silica, alumina,  water  and frequently with appreciable quantities of iron, alkalis as well as alkali earth metals. Two structural units are involved in the atomic lattices of most clay minerals. One unit consists of closely packed oxygen atoms and hydroxyls in which aluminum, iron and magnesium atoms are embedded in an octahedral combination so that they are at equal distant from six oxygen or hydroxyls. The second unit is built of silica tetrahedrons. The silica tetrahedrons (Si₄O₆(OH)₄) are arranged to form a sheet of composition².

 Clay deposits are widespread over the regions of Nigeria and are under utilized in the process industries largely because we do not have the technology. These clay deposits can be mined, purified and processed into useful raw materials for the process industries. Naturally occurring clays are alumino-silicate minerals containing sodium, potassium, and calcium, with traces of magnesium and iron which may be substituted for aluminum. The structure of these clays can be altered by heating or reaction with strong acids or alkalis to improve their adsorptive properties and colour. The majority of these clays do not possess such properties, but, may be activated by some forms of treatment and their efficiency in the bleaching of vegetable oils can be improved. Activation of clays can be accomplished by calcinations, reaction with mineral acids/alkalis, or combination of both techniques.

1.2       Research Objective and Scope

The aim of this research was to make comparative analysis of the bleaching efficiency of a locally substituted adsorbent, Nteje clay  to the imported, commercially available activated carbon and fuller’s earth. Because little or no work has been done in comparing the bleaching efficiency of Nteje clay to its commercial standards, hence the need for the study. This study if found efficient to the imported bleaching efficiencies of activated carbon and fuller’s earth, should be able to operate at various quality of crude palm oil (C.P.O) fed and produce equal results and responses as its commercial standards. By doing so, the purity of the final product including its commercial and health values will be enhanced.

Therefore, the specific objectives of the research were:-