Determination Of Optimal Conditions For Biodiesel Production From Jansa Seed Oil Using Lithium-Doped Catalysts

ABSTRACT

This study presents an empirical analysis of biodiesel production from Jansa seed oil using tranesterification process. Following the quest to achieve improved economic viability and clean production process for biodiesel, lithium ion from lithium carbonate was applied to improve the catalytic properties of calcium oxide and magnesium oxide for biodiesel production. Oil produced from jansa seed was characterized to determine its suitability for biodiesel production. Based on the characterization, an appreciable oil weight or yield of 38.09% was produced. Also, 0.493mgKOH/kg free fatty acid (FFA) content, 205.923 gKOH/kg saponification value and 99.95% ester value which specified its great tendency to be converted into methyl ester (biodiesel) were obtained. Li-CaO and Li-MgO catalysts were prepared in diverse concentrations for use in biodiesel production. Li-CaO-1.50 and Li-MgO-1.50 gave the optimal yield of 76 and 83% volume of biodiesel. These were applied to study the effects of other process parameters (reaction time, reaction temperature, agitation speed, and methanol to oil molal ratio) and optimized using a matrix design.  Li-CaO-1.50 gave the optimal yield at other process conditions. A two level, five experimental design matrix was used for transesterification studies for 32 experimental runs using Li-CaO as catalyst. Set of conditions that gave the optimal yield were; catalyst concentration of 1.5 % weight, reaction time of 3 hours, temperature of 60⁰C, methanol and oil molal ratio of 12:1 and agitation speed of 500 rpm respectively. All possible interactions, predicted and actual values, final equation in terms of coded factors and interaction plots were identified. Biodiesel blends from optimal yield of the metallic oxides of the catalysts were formulated and characterized to further determine the physicochemical properties (calorific value, anisidine point, API gravity, diesel index, flash and fire points, cloud and pour points) which were within the ASTM D6751 standard recommendations for use in compression ignition engines. Scanning electron microscopy (SEM) was used to study the active sites of the surface structure of the catalyst in relation to various modifications. The sample indicated increased points of higher porosity as lithium concentration increased (1.5, 2.0 and 2.5%) and less porosity at 0.5 and 1.0% concentration. Gas chromatography (GC) and Fourier transform infrared spectrometry (FTIR) of the jansa seed oil and biodiesel produced were carried out. A total of 7 compounds were identified in the oil of which 4 were FFAs and other 3 were biodiesel esters. For the biodiesel, a total of 12 compounds were identified, of which 9 were methyl esters and 3 non esters, thus, producing 88.35% methyl ester concentration at optimal yield sample. Evidently, the same functional groups identified in the jansa seed oil were present in the optimal biodiesel yield sample which includes; the hydrocarbon group (as a basic characteristics of bio-oil),a halide group and an ester group (as the basic characteristics of biodiesel). Overall, the optimal products developed were found to meet standard properties for biodiesel through free fatty acid methyl ester (FAME) profile test and functional group validation. At such, Li-CaO, Li-MgO, other similar materials should be adopted as catalyst for the production of biodiesel to bridge the energy gaps.

TABLE OF CONTENTS

                                                                                                                                                    Page

Cover Page                                                                                                                                       i

Title Page                                                                                                                                         ii

Declaration                                                                                                                                      ii

Dedication                                                                                                                                      iv

Certification                                                                                                                                    v

Acknowledgements                                                                                                                        vi

Table of Contents                                                                                                                          vii

List of Tables                                                                                                                                  xi

List of Figures                                                                                                                                xii

Abstract                                                                                                                                         xv

CHAPTER 1: INTRODUCTION

1.1              Background of the Study                                                                                                     1

1.2              Statement of  Problem                                                                                                                      2

1.3              Aim and Objectives of Study                                                                                               3

1.4              Scope of Study                                                                                                                     3

1.5              Justification of Study                                                                                                           4                                                           

CHAPTER 2: LITERATURE REVIEW

2.1       Catalysts and Compositional Properties                                                                               5

2.2       Basic Solid Catalysts                                                                                                            5

2.2.1    MgO as Base Heterogeneous Catalyst                                                                                 6

2.2.2    CaO as a Base Heterogeneous Catalyst                                                                                7

2.2.3    SrO as a Base Heterogeneous Catalyst                                                                                 8

2.2.4    Biodiesel Production with Mixed Metal Oxide and Derivatives                                         8

2.2.5    Biodiesel Production with Transition Metal Oxide and Derivatives                                   9

2.2.6    Waste Material-Base Heterogeneous Catalysts                                                                  11

2.3       Acidic Solid Catalysts                                                                                                                    12

2.3.1    Acid-Base Solid Catalysts                                                                                                  13

2.4       Adoption of the Catalysts for the Study                                                                             15

 2.5      Summary of Literature                                                                                                        17                                                                                                                                                                       

CHAPTER 3: MATERIALS AND METHODS

3.1       Materials                                                                                                                             19

3.1.1    Glass Wares and other Consumables                                                                                  19

3.1.2    Analytical Grade Reagents                                                                                                 19

3.1.3    Electronic Equipment                                                                                                         19

3.2       Methods                                                                                                                              19

3.2.1    Sample Collection and Preparation                                                                                     19

3.2.2    Oil Extraction (Soxhlet Method)                                                                                        20

3.2.3    Oil Characterization                                                                                                            21

3.2.4    Catalyst Preparation                                                                                                            26

3.2.5    Effects of Process Parameters on the Biodiesel Production                                               26

3.3       Design of Experiment for Biodiesel Production                                                                28

3.3.1    Fractional Factorial Design of Experiment for Biodiesel Production                               28

3.4       Biodiesel Blends Preparation and Characterization                                                           31

3.5       Gas Chromatography – Mass Spectrometry (GC-MS) Analysis of the

Raw Oil and the Biodiesel                                                                                                  33

3.6       Fourier Transform Infra-Red Spectrometry (FTIR) of Raw Oil and Biodiesel                 33

3.7       Scanning Electron Microscopy (SEM) of the Catalysts                                                     34

CHAPTER 4: RESULTS AND DISCUSSION

4.1       Characterization Test Result of the Jansa seed Bio-Oil                                                      35

4.2       Gas Chromatography Mass Spectrometry (GC-MS) Analysis

Test Results of the Jansa Seed Oil                                                                                      36

4.3       Scanning Electronic Microscopy (SEM) of the Lithium-Ions-Doped Metallic

            Oxides Catalysts for Biodiesel Production                                                                        39

4.4       Effects of the Process Parameters on the Biodiesel Production Yield

            using the Lithium-Doped CaO and MgO Catalysts Variants                                            42

4.4.1    Effect of Catalyst Concentration Variation on the Biodiesel Yield                                  43

4.4.2    Effect of Reaction Time Variation on the Biodiesel Yield                                                44

4.4.3    Effect of Reaction Temperature Variation on the Biodiesel Yield                                    44

4.4.4    Effect of Agitation Speed Variation on the Biodiesel Yield                                                         45

4.4.5    Effect of Methanol and Sample Molal Ratio Variation on the Biodiesel Yield                45

4.5       Results for Optimization Yield Studies of the Biodiesel Production using the

            Fractional Factorial Matrix Design                                                                                     46

4.5.1    Predicted and Actual Values for Biodiesel Production from the Jansa Seed Oil.             46

4.5.2    Analysis of Variance (ANOVA) for Quadratic Model                                                     48

4.5.3    Fit Statistics Results for the Biodiesel Production from the Jansa Seed Oil                     50

4.5.4    Results for the Coefficient in Terms of Coded Factors for the Biodiesel

            Production                                                                                                                          50

4.5.5    Matrix Design Final Equation Developed in Terms of Coded Factors for the Effects

            of the Process Parameters on Biodiesel Produced from the Jansa Seed Oil                      51

4.6       Interactions of Significant Variables and Process Factors on the

            Biodiesel Yield                                                                                                                   53

4.6.1    Results of the Predicted and the Actual Interactions of Variables                                    53

4.6.2    3-Dimensional (3D) Plots Interactions Results of the Process Variables

with the Biodiesel Yield.                                                                                                    53

4.7       Characterization of the Developed Biodiesel from the Jansa Seed Oil                              59

4.7.1    Physicochemical Characterization Test Result of the Optimal Biodiesel

Yield and the Blends from the Jansa Seed Oil.                                                                  59

4.7.2    Gas Chromatography of the Optimal Biodiesel Yield from the Jansa Seed Oil                65

4.7.3    Fourier Transfer Infrared Test Results of the Optimal Biodiesel Yield                            68

CHAPTER 5: CONCLUSION AND RECOMMENDATIONS

5.1       Conclusion                                                                                                                          69

5.1.1    Contributions to Knowledge of this Study                                                                        71

5.2       Recommendations                                                                                                              71

            References                                                                                                                          72

           Appendices                                                                                                                          81

LIST OF TABLES

                                                                                                                                                             Page

3.1       Studied range of each factor in actual and coded form for heterogeneous catalysts         29

3.2       Experimental design matrix for transesterification studies catalyzed by

            lithium-ions-doped calcium and magnesium oxides                                                           30                   

4.1       Physicochemical properties of the jansa bio-oil                                                                  35

4.2       FFAs profile identified in Cussonia bateri seed oil by GC                                                38

4.3       Fourier transform infrared spectrometry (FTIR) analysis of raw jansa seed oil                39

4.4       Predicted and actual values for biodiesel production from the jansa seed oil                    47           

4.5       ANOVA results for quadratic model for the jansa seed oil biodiesel production

            (Response 1: Biodiesel yield)                                                                                                        49

4.6       Fit Statistics result for the biodiesel production                                                                 50

4.7       Results for the coefficients in terms of the coded factors for the biodiesel

            production                                                                                                                           51

4.8       Methyl esters identified in the optimal biodiesel yield by gas chromatography                67      4.9            FTTR analysis of the optimal biodiesel yield from the jansa seed oil                     68     

LIST OF FIGURES

Page

2.1       Mechanism of SrO catalyst transesterification adapted                                                      8

2.2       Flow chart for biodiesel production from heterogeneous catalyst (Lee et al., 2015)        10

3.1       Soxhlet apparatus set-up for bio-oil extraction from jansa seed                                        20

4.1       Gas chromatography column over ramping schedule of the jansa seed oil                       36 

4.2       Gas chromatograph of Cussonia bateri seed oil showing elution peaks of FFAs             37

4.3       Fourier transform infrared spectrometry (FTIR) of oil jansa seed oil                     39

4.4       Scanning electron microscopy of lithium doped metal oxides                                          42

4.5       Variation of biodiesel yield with catalyst variants for the initial biodiesel production     43

4.6       Effect of process conditions variation on biodiesel yield                                                  43

4.7       Effect of reaction time variation on the biodiesel yield                                                     44

4.8       Effect of reaction temperature variation on the biodiesel yield                                         44

4.9       Effect of agitation speed variation on the biodiesel yield                                                  45

4.10     Effect of methanol and sample molal ratio variation on the biodiesel yield                     45

4.11     Predicted versus actual plots for the biodiesel yield                                                          53

4.12     3D plot of Catalyst concentration and reaction temperature with biodiesel yield             54

4.13     3D plot of Catalyst concentration and reaction time with biodiesel yield                         54

4.14     3D plot of Catalyst concentration and agitation speed with biodiesel yield                      55

4.15     3D plot of Catalyst concentration and molal ratio with biodiesel yield                            55

4.16     3D plot of reaction temperature and reaction time with biodiesel yield                            56

4.17     3D plot of reaction temperature and agitation speed for the biodiesel yield                     57

4.18     3D plot of reaction temperature and molal ratio for the biodiesel yield                            57

4.19     3D plot of reaction time and agitation speed with biodiesel yield                                     58

4.20     3D plot of reaction time and molal ratio with the biodiesel yield                                     58

4.21     3D plot of agitation speed and molal ratio with the biodiesel yield                                  59

4.22     Variations of specific gravity with the fuel blends                                                            59                                     

4.23     Variations of kinetic viscosity with the fuel blends                                                           60

4.24     Variations of flash point with the fuel blends                                                                    61

4.25     Variations of fire point with the fuel blends                                                                      61

4.26     Variation of cloud point with the fuel blends                                                                    62

4.27     Variations of pour point with the fuel blends                                                                    62

4.28     Variations of free fatty acid with the fuel blends                                                              63

4.29     Variations of API gravity with the fuel blends                                                                  63

4.30     Variations of anisidine value with the fuel blends                                                             64

4.31     Variation of diesel index with the fuel blends                                                                   64

4.32     Variation of calorific value with the fuel blends                                                               65

4.33     Gas chromatography column-oven ramping schedule of methyl ester (biodiesel)

             analysis                                                                                                                              66

4.34     Chromatogram of the optimal biodiesel yield from the jansa seed oil showing elution

            peaks of the methyl ester                                                                                                    67

4.35    Fourier transform infrared spectrometry (FTIR) of the optimal biodiesel yield from

           jansa seed oil                                                                                                                       68