The potential use of hydrogen as a clean and renewable fuel resource has generated significant attention in recent years, especially given the rapidly increasing demand for energy sources and the dwindling availability of fossil fuels. Hydrogen is an ideal fuel in several ways. Its only byproduct of consumption is water; it is the most abundant element in the universe; and it is available at low cost. Hydrogen generation is possible via a number of possible chemical processes, to separate the hydrogen from its bond with atoms such as carbon, nitrogen, and oxygen.
In this book, the authors provide the scientific foundations for established and innovative methods of hydrogen extraction; outline solutions for its storage; and illustrate its applications in the fields of petroleum, chemical, metallurgical, physics, and manufacturing.
Addresses the three fundamental aspects of hydrogen as a fuel resource: generation, storage, and utilizationProvides theoretical basis for the chemical processes required for hydrogen generation, including solar, photoelectrochemical, thermochemical, and fermentation methodsDiscusses storage of hydrogen based on metal hydrides, hydrocarbons, high pressure compression, and cryogenicsExamines the applications of hydrogen utilization in the fields of petroleum, chemical, metallurgical, physics, and manufacturingContains over 90 figures, including 27 color figures
Preface ix
Acknowledgments xiii
1 Introduction to Basic Properties of Hydrogen 1
1.1 Basics about the Hydrogen Element 1
1.2 Basics about the Hydrogen Molecule 3
1.3 Other Fundamental Aspects of Hydrogen 4
1.4 Safety and Precautions about Hydrogen 5
References 5
2 Hydrocarbons for Hydrogen Generation 7
2.1 Basics about Hydrocarbons 7
2.2 Steam Methane Reforming 8
2.3 Partial Oxidation 10
2.4 Methanol and Ethanol Steam Reforming 12
2.5 Glycerol Reforming 15
2.5.1 Glycerol Reforming Processes 15
2.5.2 Mechanistic Aspects of Glycerol Reforming Reactions 17
2.5.3 Catalytic Reforming of Glycerol 17
2.6 Cracking of Ammonia and Methane 18
2.6.1 Ammonia Cracking 18
2.6.2 Methane Cracking 22
2.6.3 Other Decomposition Methods 23
2.7 Summary 24
References 25
3 Solar Hydrogen Generation: Photocatalytic and Photoelectrochemical Methods 27
3.1 Basics about Solar Water Splitting 27
3.2 Photocatalyic Methods 28
3.2.1 Background 28
3.2.2 Metal Oxides 29
3.2.3 Metal Oxynitrides/Metal Nitrides/Metal Phosphides 31
3.2.4 Metal Chalcogenides 32
3.2.5 Conclusion 35
3.3 Photoelectrochemical Methods 36
3.3.1 Background 36
3.3.2 Photocathode for Water Reduction 36
3.3.3 Photoanode for Water Oxidation 40
3.3.4 Conclusion 45
3.4 Summary 45
References 46
4 Biohydrogen Generation and Other Methods 51
4.1 Basics about Biohydrogen 51
4.2 Pathways of Biohydrogen Production from Biomass 52
4.3 Thermochemical Conversion of Biomass to Hydrogen 55
4.3.1 Hydrogen from Biomass via Pyrolysis 55
4.3.2 Hydrogen from Biomass via Gasifi cation 58
4.3.3 Hydrogen from Biomass via Supercritical Water (FluidGas) Extraction 60
4.3.4 Comparison of Thermochemical Processes 61
4.4 Biological Process for Hydrogen Production 62
4.4.1 Biophotolysis of Water Using Microalgae 64
4.4.2 Photofermentation 66
4.4.3 Dark Fermentation 66
4.4.4 Two-Stage Process: Integration of Dark and Photofermentation 67
4.5 Summary 69
References 69
5 Established Methods Based on Compression and Cryogenics 75
5.1 Basic Issues about Hydrogen Storage 75
5.2 High Pressure Compression 78
5.3 Liquid Hydrogen 84
5.4 Summary 89
References 90
6 Chemical Storage Based on Metal Hydrides and Hydrocarbons 91
6.1 Basics on Hydrogen Storage of Metal Hydrides 91
6.2 Hydrogen Storage Characteristics of Metal Hydrides 92
6.2.1 Storage Capacities 93
6.2.2 Thermodynamics and Reversible Storage Capacity 93
6.2.3 Hydrogenation and Dehydrogenation Kinetics 95
6.2.4 Cycling Stability 99
6.2.5 Activation 99
6.3 Different Metal Hydrides 100
6.3.1 Binary Metal Hydrides 100
6.3.2 Metal Alloy Hydrides 100
6.3.3 Complex Metal Hydrides 101
6.3.4 Improving Metal Hydride Performance 102
6.4 Hydrocarbons for Hydrogen Storage 108
6.4.1 Reaction between Carbon Atom and Hydrogen 109
6.4.2 Reaction between Solid Carbon and Hydrogen 110
6.4.3 Reaction between Carbon Dioxide and Hydrogen 111
6.5 Summary 115
References 116
7 Physical Storage Using Nanostructured and Porous Materials 121
7.1 Physical Storage Using Nanostructures 121
7.1.1 Carbon Nanostructures 121
7.1.2 Other Nanostructures and Microstructures 129
7.2 Physical Storage Using Metal-Organic Frameworks 130
7.3 Clathrate Hydrates 132
7.4 Summary 135
References 135
8 Hydrogen Utilization: Combustion 139
8.1 Basics about Combustion 139
8.2 Mechanism of Combustion 140
8.3 Major Factors Affecting Combustion 143
8.4 Catalytic Combustion 146
8.5 Summary 149
References 150
9 Hydrogen Utilization: Fuel Cells 153
9.1 Basics of Fuel Cells 153
9.1.1 The Rational Development of Fuel Cells 153
9.1.2 Work Principles of Fuel Cells 154
9.1.3 Operation of Fuel Cells 155
9.2 Types of Fuel Cells 157
9.2.1 Alkaline Fuel Cell (AFC) 157
9.2.2 Proton Exchange Membrane Fuel Cell (PEMFC) 157
9.2.3 Phosphoric Acid Fuel Cell (PAFC) 160
9.2.4 Molten Carbonate Fuel Cell (MCFC) 162
9.2.5 Solid Oxide Fuel Cell (SOFC) 163
9.3 Catalysts for Oxygen Reduction Reaction of Fuel Cells 163
9.3.1 Pt-Based Catalysts 164
9.3.2 Nonnoble Metal Catalysts 164
9.4 Fuel Processing 168
9.5 Applications of Fuel Cells 169
9.6 Summary 171
References 172
10 Hydrogen Utilization in Chemical Processes 177
10.1 Background 177
10.2 Hydrogen Utilization in Petroleum Industry 177
10.2.1 Hydrocracking 177
10.2.2 Hydroprocessing 180
10.3 Hydrogen Utilization in Chemical Industry 181
10.3.1 Ammonia Production: The Haber Process 181
10.3.2 Hydrogenation of Unsaturated Hydrocarbons 182
10.4 Hydrogen Utilization in Metallurgical Industry 182
10.4.1 Ore Reduction 182
10.5 Hydrogen Utilization in Manufacturing Processes 184
10.5.1 Welding Gas: Oxy-Hydrogen Welding 184
10.5.2 Coolant 185
10.6 Hydrogen Utilization in Physics 187
10.6.1 Lifting Gas 187
10.6.2 Superconductor Industry 187
10.6.3 Semiconductor Industry 187
10.7 Summary 188
References 188
Index 191