Chemistry of Fossil Fuels and Biofuels

Transcription

1 Chemistry of Fossil Fuels and Biofuels HAROLD SCHOBERT The Pennsylvania State University and North-West University CAMBRID GE UNIVERSITY PRESS

2 Contents Preface page xv Acknowledgments xvii Acknowledgments for permissions to use illustrations xviii 1 Fuels and the global carbon cycle 1 Notes 8 2 Catalysis, enzymes, and proteins Catalysis Proteins Enzymes 13 Notes 17 3 Photosynthesis and the formation of polysaccharides Water splitting in photosynthesis Carbon dioxide fixation Glucose, cellulose, and starch 27 Notes 32 4 Ethanol Fermentation chemistry Commercial production of ethanol via fermentation Ethanol as a motor vehicle fuel Issues affecting possible large-scale production of fuel ethanol Cellulosic ethanol 48 Notes 49 5 Plant oils and biodiesel Biosynthesis of plant oils Direct use of vegetable oils as diesel fuel Transesterification of plant oils Biodiesel 62 Notes 66

3 viii Contents 6 Composition and reactions of wood Wood combustion Wood pyrolysis Charcoal Methanol Wood gasification Wood saccharification and fermentation 83 Notes 84 7 Reactive intermediates Bond formation and dissociation Radicals Initiation reactions Propagation reactions Termination reactions Radical reactions with oxygen Carbocations Hydrogen redistribution 100 Notes Formation of fossil fuels Diagenesis: from organic matter to kerogen Catagenesis: from kerogen to fossil fuels Catagenesis of algal and liptinitic kerogens Catagenesis of humic kerogen Summary 127 Notes Structure property relationships among hydrocarbons Intermolecular interactions Volatility Melting and freezing Density and API gravity Viscosity Water solubility Heat of combustion The special effects of aromaticity 156 Notes Composition, properties, and processing of natural gas Gas processing Dehydration Gas sweetening 166

4 Contents ix Separation of C2+ hydrocarbons Natural gas as a premium fuel 170 Notes Composition, classification, and properties of petroleum Composition Alkanes Cycloalkanes Aromatics Heteroatomic compounds Inorganic components Classification and properties of petroleums API gravity Carbon preference index Age depth relationships Composition relationships Asphalts, oil sands, and other unconventional oils 187 Notes Petroleum distillation Desalting Principles of distillation Refinery distillation operations Atmospheric-pressure distillation Vacuum distillation Introduction to petroleum distillation products Gasoline Naphtha Kerosene Diesel fuel Fuel oils Lubricating oils Waxes Asphalt 204 Notes Heterogeneous catalysis Catalytic materials The active species The support The promoter Preparation Adsorption an catalyst surfaces Mechanisms of catalytic reactions 216

5 x Contents 13.4 Measures of catalyst performance Surface effects an catalysts 219 Notes Catalytic routes to gasoline Gasoline combustion Specifications and properties of gasoline Refinery routes to enhanced yield and quality Alkylation and polymerization Catalytic cracking Cracking catalysts Cracking reactions Practical aspects Catalytic reforming Reforming catalysts Reforming reactions Practical aspects Methanol to gasoline 251 Notes Middle distillate fuels Middle distillate fuel products Kerosene Jet fuel Diesel fuel Fuel oils Hydroprocessing Hydrodesulfurization Hydrodenitrogenation Hydrodemetallation Hydrofining Hydrocracking Hydrogenation Sources of hydrogen 277 Notes Thermal processing in refining Thermal cracking Visbreaking Coking processes Delayed coking Fluid coking and Flexicoking 292 Notes 293

6 Contents xi 17 Composition, properties, and ciassification of coals Classification of coal by rank The caking behavior of bituminous coals Elemental composition The macromolecular structures of coals Coals as heterogeneous solids Physical properties 314 Notes The inorganic chemistry of coals The origin of inorganic components in coals Inorganic composition of coals Minerals in coals and their reactions Coal cleaning Behavior of inorganic components during coal utilization 334 Notes Production of synthesis gas Steam reforming of natural gas Partial oxidation of heavy oils Coal and biomass gasification Fundamentals of the carbon steam and related reactions Coal gasification processes Fixed-bed gasification Fluidized-bed gasification Entrained-flow gasification Underground coal gasification Biomass gasification 360 Notes Gas treatment and shifting Gas clean-up Acid gas removal The water gas shift 371 Note Uses of synthesis gas Fuel gas Methanation Methanol synthesis Fischer Tropsch synthesis Kölbel reaction 389

7 xii Contents 21.6 Oxo synthesis Gas to liquids The potential of synthesis gas chemistry 392 Notes Direct production of liquid fuels from coal Pyrolysis Solvent extraction Direct coal liquefaction Principles Direct liquefaction processing 406 Notes Carbonization and coking of coal Thermal decomposition of coals Low- and medium-temperature carbonization The special case of bituminous coals Chemistry of coke formation Industrial production of metallurgical coke 426 Notes Carbon products from fossil and biofuels Activated carbons Aluminum-smelting anodes Carbon blacks Graphites Natural graphite Graphitization processes Electrodes High-density isotropic graphites 449 Notes Carbon dioxide Carbon capture and storage Algae Biochar Chemical uses of CO Coalbed methane recovery Enhanced oil recovery Mineral carbonation Photocatalysis 464

8 Contents xiii Underground injection Urea synthesis Conclusions 468 Notes 469 Index 472