1    INTRODUCTION    

   1.1    Energy Sources    

   1.2    Problem Statement    

   1.3    Scope of Study    

   1.4    Research Objectives    

2    LITERATURE REVIEW    

   2.1    Energy Crisis    

   2.2    Bioethanol as Alternative of Fossil Fuel    

       2.2.1    Feedstock for Bioethanol Production    

   2.3    Overview of Coconut Palm    

       2.3.1    Coconut Husk    

   2.4    Compositions of Lignocellulosic Materials    

       2.4.1    Cellulose    

       2.4.2    Hemicellulose    

       2.4.3    Lignin    

   2.5    Lignocelluloses Bioconversion Technology    

       2.5.1    Pretreatment Process    

       2.5.2    Saccharification Process    

       2.5.3    Fermentation Process    

   2.6    Batch Production of Bioethanol    

   2.7    Factors Affecting Bioethanol Fermentation by Yeast    

       2.7.1    Temperature    

       2.7.2    pH    

       2.7.3    Carbon Source    

       2.7.4    Nitrogen Source    

   2.8    Concluding Remarks    

 3    GENERAL MATERIALS AND METHODS    

   3.1    Chemical Reagents    

   3.2    Microorganism and Maintenance    

   3.3    Inoculums Preparation    

   3.4    Analytical Procedures    

       3.4.1    Determination of Reducing Sugar Concentration    

       3.4.2    Determination of Ethanol Concentration    

       3.4.3    Determination of Ethanol Productivity    

       3.4.4    Viable Cell Counts    

   3.5    Experimental Designs of Project Works    

1.    COMPARISON OF PRETREATMENT STRATEGIES ON 49 CONVERSION OF COCONUT HUSK FIBER TO

FERMENTABLE SUGARS    

4.1    Introduction    

4.2    Materials and Methods    

   4.2.1    Collection and Processing of Coconut Husk    

   4.2.2    Pretreatments on Coconut Husk    

   4.2.3    Enzymatic Hydrolysis Process    

   4.2.4    Characterisation of Pretreated Coconut Husk    

   4.2.5    Scanning Electron Microscopy (SEM) Analysis    

   4.2.6    Data analysis    

4.3    Results and Discussions    

   4.3.1    Effect of Different Pretreatment Techniques    

       Coconut Husk for Production of Reducing Sugar    

   4.3.2    Characterization of Pretreated Coconut Husk    

   4.3.3    Comparison of Pretreatment Techniques    

   4.3.4    Scanning Electron Microscope (SEM) Analysis    

4.4    Concluding Remarks    

1.    STATISTICAL OPTIMISATION OF BIOETHANOL 72 PRODUCTION USING MAA-PRETREATED COCONUT

   HUSK            

   5.1    Introduction        

   5.2    Materials and Methods        

       5.2.1    Optimization of Simultaneous Saccharification        

           and Fermentation Process        

       5.2.2    Gas Chromatography-Mass Spectrometry (GC-        

           MS) Analysis        

       5.2.3    Data Analysis        

   5.3    Results and Discussions        

       5.3.1    Screening of Significant Factors by Plackett-        

           Burman Design        

       5.3.2    Path of Steepest Ascent        

       5.3.3    Optimization of Ethanol Productivity by using        

           Response Surface Methodology (RSM)        

       5.3.4Validation of Bioethanol Fermentation using    

       Optimized Condition    

       5.3.5Gas Chromatography-Mass Spectrometry    

       (GC-MS) Analysis of Bioethanol    

   5.4    Concluding Remarks    

6    CONCLUSIONS   AND   RECOMMENDATIONS   FOR    

   FUTURE RESEARCH    

   6.1    Conclusions    

   6.2    Recommendations for Future Research    

REFERENCES    

APPENDIX  

                               

 LIST OF TABLES

Table        Page

2.1    Comparison of first and second generation bioethanol    

2.2    Bioethanol production from various lignocellulosic    

   feedstock    

2.3    Comparison of lignocellulose in several sources on dry    

   basis    

2.4    The common pretreatments and their possible effects    

3.1    Formulation of NDF solution    

3.2    Formulation of ADF solution    

4.1    Cellulose, hemicellulose and lignin contents of the    

   pretreated coconut husks    

5.1    Experimental range and levels of independent variables in    

   the Plackett-Burman experiment    

5.2    Plackett-Burman design matrix representing the coded    

   values for 7 independent variables    

5.3    Path of steepest ascent experiment design    

5.4    Levels of the factors tested in central composite design    

5.5    The central composite design of RSM for optimization of    

   bioethanol production    

5.6    Plackett-Burman design matrix representing 7 independent    

   variables and the response    

 5.7    Statistical analysis of the model (ANOVA)    

5.8    Step size for substrate and pectinase loading    

5.9    Experiment design and results for the path of steepest    

   ascent    

5.10    The Central Composite Design and results of RSM for    

   optimization of bioethanol production    

5.11    Model summary and analysis of variance (ANOVA) for    

   the quadratic model  

 LIST OF FIGURES

Figure        Page

2.1    Cocos nucifera L.    

2.2    Cross-section of the fruit of Cocos nucifera L.    

2.3    Coconut husk    

2.4    A schematic diagram of plant cell wall showing cellulose    

   fibrils laminated with hemicellulose and lignin polymers    

2.5    The structure of cellulose    

2.6    The structure of hemicelluloses    

2.7    ρ-coumaryl (1), coniferyl (2) and sinapyl (3) alcohols:    

   dominant building blocks of the three dimensional lignin    

2.8    Schematic presentation of effects of pretreatment on    

   lignocellulosic biomass    

2.9    General nature of batch culture    

3.1    Glucose standard curve    

3.2    Standard curve for ethanol determination    

3.3    Protocol in performing serial dilution    

3.4    Overall process in bioethanol production by using coconut    

   husk as lignocellulosic raw material  

 4.1    Level of reducing sugar released from coconut husk with    

   two different particle sizes after enzymatic hydrolysis    

   process    

4.2    Level of reducing sugar produced through hydrolysis of    

   thermally-treated coconut husk    

4.3    Level of reducing sugars using acid pretreated coconut husk    

4.4    Level of reducing sugars produced through hydrolysis of    

   alkaline-treated (5% w/v of NaOH for 24 hours) coconut    

   husk    

4.5    Level of reducing sugars produced through hydrolysis of    

   microwave-assisted-alkaline-treated coconut husk    

4.6    Maximum level of reducing sugars produced from the    

   pretreated coconut husk    

4.7    SEM images of coconut husk after several pretreatment    

   process    

5.1    Schematic diagram of simple distillation process    

5.2    Pareto chart    

5.3    Main effect plots    

5.4    Response surface curve for bioethanol productivity showing    

   the interaction between substrate and pectinase loading    

5.5    Profile of enzymatic hydrolysis and bioethanol fermentation    

   by Saccharomyces cerevisiae at optimum conditions    

5.6    Gas Chromatography-Mass Spectrometry analysis