Production of biodiesel using lipase encapsulated in κ-carrageenan (SpringerBriefs in Bioengineering)

This book explores a novel technique for processing biodiesel using lipase immobilization by encapsulation and its physical properties, stability characteristics, and application in stirred tank and re-circulated packed bed immobilized reactors for biodiesel production. The enzymatic processing of biodiesel addresses many of the problems associated with chemical processing. It requires only moderate operating conditions and yields a high-quality product with a high level of conversion and the life cycle assessment of enzymatic biodiesel production has more favourable environmental consequences. The chemical processing problems of waste water treatment are lessened and soap formation is not an issue, meaning that waste oil with higher FFA can be used as the feedstock. The by product glycerol does not require any purification and it can be sold at higher price. However, soluble enzymatic processing is not perfect. It is costly, the enzyme cannot be recycled and its removal from the product is difficult. For these reasons, immobilized enzymatic process has been developed which retains the advantages of the soluble enzymatic process and reuse of the enzyme is possible which decreases the enzyme cost, the biodiesel produced does not contain any enzyme residue and the activity of the enzyme can be increased by immobilization. The drawbacks of the immobilized enzyme process are mass transfer limitation, enzyme leakage, the lack of a versatile commercial immobilized enzyme and some of immobilization methods involve toxic chemicals. To overcome the drawbacks of the immobilized enzyme, an attempt is made to use a degradable biopolymer (κ-carrageenan) as a carrier for lipase immobilization. Dedication 6 Contents 8 Chapter 1: Introduction 12 1.1 Renewable Energy 12 1.2 Biofuels 14 1.3 History of Biodiesel 15 1.4 Global Biodiesel Production 16 1.5 Palm Oil 18 1.5.1 History 18 1.5.2 Palm Oil-Global Scenario 18 1.5.3 Malaysian Scenario 19 1.6 Biodiesel in Malaysia 20 1.7 White Biotechnology 21 1.8 Biodiesel Production Using Lipase Enzymes 22 1.9 Immobilization 23 1.10 Biopolymer Material 24 1.11 Research Background 24 1.12 Life Cycle Assessment (LCA) 26 1.13 Economic Assessment 28 1.13.1 Factors of Economic Assessment 28 1.14 Research Problem 29 1.15 Approach 30 1.16 Scope 30 References 30 Chapter 2: Literature Review 33 2.1 Biodiesel 37 2.2 Process Description 37 2.2.1 Homogeneous Alkaline Catalyst 38 2.2.2 Homogeneous Acid Catalyst 41 2.2.3 Homogeneous Enzyme Catalyst 42 2.2.4 Homogeneous Whole Cell Microorganisms 42 2.2.5 Transesterification Without Catalysts 42 2.2.6 Heterogeneous Alkali Catalyst 43 2.2.7 Heterogeneous Acid Catalyst 43 2.2.8 Heterogeneous Whole Cell Micro Organism 43 2.2.9 Heterogeneous Enzyme Catalyst 43 2.3 Immobilization 44 2.3.1 Various Lipase Immobilization Techniques Used for Biodiesel Production 44 2.3.2 Adsorption 45 2.3.3 Covalent Binding 48 2.3.4 Cross-Linking 48 2.3.5 Entrapment 49 2.3.6 Encapsulation 49 2.3.7 Other Immobilization Techniques 50 2.4 Factors Affecting the Production of Biodiesel Using Immobilized Lipase 51 2.4.1 Pretreatment of Immobilized Lipase 51 2.4.2 Feedstock 51 2.4.3 Lipase Enzyme 53 2.4.4 Acyl Acceptors 55 2.4.5 Water Content 57 2.5 Immobilized Bioreactors and Operation Mode 57 2.5.1 Stirred Tank Bioreactor 58 2.5.2 Packed Bed Bioreactors 58 2.5.3 Operational Mode 59 2.5.4 Batch Mode 59 2.5.5 Fed Batch Mode 59 2.5.6 Continuous Mode 60 2.6 Kinetics of Biodiesel Production Using Immobilized Lipase 60 2.7 Carrageenan as a Matrix for Lipase Immobilization 62 2.8 Methods for Biocatalyst Immobilization in Carrageenan 64 2.8.1 Gel Method 64 2.8.2 Droplet Method 65 2.8.3 Emulsion Method 65 2.8.4 Dehydration Method 65 2.9 LCA Studies on Biodiesel Production 66 2.10 Economical Assessment of Biodiesel Production 67 References 69 Chapter 3: Materials and Methods 74 3.1 Materials 74 3.2 Methods 76 3.2.1 Lipase Encapsulation 76 3.2.2 Capsule Size and Coefficient of Variance 77 3.2.3 Moisture Content 77 3.2.4 Immobilization Efficiency 77 3.2.5 Surface and Internal Morphologies of Encapsulated Lipase 78 3.2.6 Interaction Between κ-Carrageenan and Lipase 78 3.2.7 Lipase Activity 78 3.2.8 pH Stability 79 3.2.9 Temperature Stability 79 3.2.10 Solvent Stability 80 3.2.11 Storage Stability 80 3.2.12 Reusability of the Immobilized Lipase 80 3.2.13 Reaction Conditions and Optimization of the Biodiesel Production in Stirred Tank Batch Reactor 80 3.2.14 Effect of Oil and Methanol Ratio 81 3.2.15 Effect of Water Concentration 81 3.2.16 Effect of Enzyme Loading 81 3.2.17 Effect of Temperature 81 3.2.18 Effect of Reaction Time 81 3.2.19 Effect of Mixing Intensity 82 3.2.20 Reusability of Immobilized Enzyme 82 3.2.21 Reaction Conditions and Optimization of Biodiesel Production in Packed Bed Batch Reactor 82 3.2.22 Effect of Flow Rate 82 3.2.23 Effect of Reaction Time 82 3.2.24 Biodiesel Sampling and Analysis 83 3.2.25 Life Cycle Assessment (LCA) 83 3.2.26 Goal and Scope of the Study 83 3.2.27 Impact Assessment 84 3.2.28 Inventory Analysis 85 3.2.29 Economic Assessment of Biodiesel Production 85 3.2.30 Process Flow Sheets, Time Chart, and Costs 88 References 93 Chapter 4: Results and Discussion 94 4.1 Lipase Encapsulation 94 4.2 Physical Characteristics of Encapsulated Lipase Capsule 95 4.2.1 Capsule Size 95 4.2.2 Moisture Content 96 4.2.3 Immobilization Efficiency 96 4.2.4 Surface and Internal Morphologies of Encapsulated Lipase 97 4.2.5 Interaction Between κ-Carrageenan and Lipase 97 4.3 Stability Characteristics of Encapsulated Lipase 99 4.3.1 pH Stability 99 4.3.2 Temperature Stability 101 4.3.3 Solvent Stability 102 4.3.4 Storage Stability 103 4.3.5 Reusability of Immobilized Lipase 104 4.4 Kinetic Parameters 104 4.5 Biodiesel Production from Palm oil Using Encapsulated Lipase in Batch Immobilized Bioreactor 106 4.5.1 Effect of Oil and Methanol Ratio 106 4.5.2 Effect of Water Concentration 107 4.5.3 Effect of Immobilized Enzyme Loading 107 4.5.4 Effect of Temperature 109 4.5.5 Effect of Reaction Time 109 4.5.6 Effect of Mixing Intensity 110 4.5.7 Reusability of Immobilized Enzyme 111 4.6 Production of Biodiesel Using Immobilized Lipase in Recirculated Packed Bed Immobilized Bioreactor 113 4.6.1 Effect of Flow Rate 113 4.6.2 Effect of Reaction Time 114 4.6.3 Comparison of Biodiesel Production in Stirred Tank Immobilized Bioreactor With Recirculated Packed Bed Immobilized Bioreactor 115 4.7 Kinetics and Modelling of Biodiesel Production Using Encapsulated Lipase 115 4.7.1 Diffusion Effect of к-Carrageenan Encapsulated Lipase in Biodiesel Production 119 4.8 Catalytic and Non-Catalytic Functions of κ-Carrageenan Encapsulated Lipase 121 4.8.1 Catalytic Function 121 4.8.2 Isolation of Catalyst from the Application Environment 122 4.8.3 Stability 122 4.8.4 Eco-Friendly Factors 123 4.9 Life Cycle Assessment (LCA) of Biodiesel Production 123 4.10 Economic Assessment of Biodiesel Production 128 4.11 Conclusion 130 References 131 Nomenclature 134 This book℗lexplores℗la novel technique for processing biodiesel using℗llipase immobilization by encapsulation and its physical properties, stability characteristics,℗land application in stirred tank and re-circulated packed bed immobilized reactors for biodiesel production. The enzymatic processing of biodiesel addresses many of the problems associated with chemical processing. It requires only moderate operating conditions and yields a high-quality product with a high level of conversion and the life cycle assessment of enzymatic biodiesel production has more favourable environmental consequences. The chemical processing problems of waste water treatment are lessened and soap formation is not an issue, meaning that waste oil with higher FFA can be used as the feedstock. The by product glycerol does not require any purification and it can be sold at higher price. However, soluble enzymatic processing is not perfect. It is costly, the enzyme cannot be recycled and its removal from the product is difficult. For these reasons, immobilized enzymatic process has been developed which retains the advantages of the soluble enzymatic process and reuse of the enzyme is possible which decreases the enzyme cost, the biodiesel produced does not contain any enzyme residue and the activity of the enzyme can be increased by immobilization. The drawbacks of the immobilized enzyme process are mass transfer limitation, enzyme leakage, the lack of a versatile commercial immobilized enzyme and some of immobilization methods involve toxic chemicals. To overcome the drawbacks of the immobilized enzyme, an attempt is made to use a degradable biopolymer (lð-carrageenan) as a carrier for lipase immobilization Front Matter....Pages i-x Introduction....Pages 1-21 Literature Review....Pages 23-63 Materials and Methods....Pages 65-84 Results and Discussion....Pages 85-124 Back Matter....Pages 125-125