Harry Marsh Francisco Rodnguez-Reinoso

(eds.)

SCIENCES OF

CARBON MATERIALS

UNIVERSIDAD DE ALICANTE

Contents

Dedication (V) Preface (VII) Acknowledgements (IX) Biographies of Contributors (XI) Chapter Summaries (XXI) Contents (XXVII)

1. Structure in Carbons and Carbon Artifacts Xavier Bourrat 1 Introduction 1 2 Bonding in Carbons: the Different Allotropes 3

2.1 Diamond Structures 5 2.2 Graphite Structures 5 2.3 Fullerenes 6 2.4 Other Carbon Allotropes 7 2.5 Amorphous Carbon 8

3 Graphitization and Structure by X-ray Diffraction 8 3.1 The Graphitization Process 8 3.2 Paracrystalline Structure of Graphitic Carbons 12 3.3 Diffractions from Paracrystalline Structures 14 3.4 X-ray Diffraction Techniques 17

4 Structure of Cokes 28 4.1 Mesophase Development and Coke GraphitizabiUty 28 4.2 Optical Texture of Coke 29 4.3 The Four Stages of Coking and Graphitization as Studied

by ТЕМ 31 4.4 Quantification of Coke Texture by ТЕМ 35

5 Structure in Carbon Blacks 40 5.1 Carbon Structure in Carbon Blacks 40 5.2 Growth and Texture of Carbon Blacks 44 5.3 Structure and Properties: Electrical Conductivity 46

6 Fibre Structures 50 6.1 PAN-, Pitch-and Rayon-Based Carbon Fibres 50 6.2 Relevant Structural Parameters and Mechanical Properties 50 6.3 Measurement of Structural Parameters 54 6.4 Disclinations in Mesophase Pitch-Based Carbon Fibres 63 6.5 SEM Fracture Examination (Texture and Raws) 63

7 Pyrocarbon 71 7.1 Differences in Pyrocarbons 71 7.2 Optical Texture of Pyrocarbons 79 7.3 Optical Anisotropy Measurement 79

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7.4 Preferred-Orientation and Structural Parameters Measured by XRD 82

7.5 Preferred-Orientation and Structural Parameters Measured by Electron Diffraction 82

8 Conclusions 87 9 Glossary of Terms and Symbols 88 10 Acknowledgements 90 11 References 90

2. New Structures in Carbon-Based Materials Jaroslav Fiala 1 Structurals Forms of Carbon 99 2 Fullerene Growth-Kinetics 105 3 Dangling Bonds 111 4 References 114

3. Carbon Materials for Nuclear Energy Applications Timothy D. Burchell 1 2

5 6 7

Introduction Fission Reactor Applications 2.1 Background 2.2 Moderator Materials Selection 2.3 Graphite Moderated Reactors 2.4 Reactor Environmental Effects 2.5 Other Fission Reactor Applications Fusion Reactor Applications 3.1 Background 3.2 Thermal Shock 3.3 Physical Sputtering, Chemical Erosion and Radiation

Enhanced Sublimation 3.4 Physical Sputtering 3.5 Chemical Erosion 3.6 Radiation Enhanced Sublimation 3.7 Tritium Retention Neutron Irradiation Effects 4.1 Background 4.2 Radiation Damage Mechanism and Induced Structural

and Dimensional Changes 4.3 Stored Energy 4.4 Physical Property Effects Space Nuclear Applications Concluding Remarks Acknowledgements References

117 118 118 119 120 123 125 125 125 128

129 130 130 131 131 132 132

133 136 138 141 145 145 145

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Carbon Materials in the Semi-Conductor Industry Masaaki Kawakami, Koji Kuroda and Isao Mochida 1 Introduction 149 2 Requirements of Carbon Materials in Semi-Conductor

Manufacture 151 3 Carbon in Silicon Semi-Conductor Manufacture 152

3.1 Manufacture of Polycrystalline Silicon 152 3.2 Single Crystal Silicon 153 3.3 Single Crystal Silicon Rod 156 3.4 Epi-(silicon) Wafer 157 3.5 CVD Films on Wafers 160 3.6 Dry Etching Cathode 161 3.7 Impurity Injection 162

4 Carbons in the Manufacture of Compound Semi-Conductors 164 4.1 Single crystal compound 164 4.2 Epitaxial Growth from Liquid Phase 165 4.3 CVD of Organometallic Compounds on to Wafers 166

5 Carbon Artifacts for Semi-Conductor Manufacture 167 6 Purification of Graphite Artifacts 169 7 Future Developments in Carbons for Semi-Conductor

Manufacture 171 8 References 172

Tar and Pitch: Composition and Application Rosa Menendez, Jenaro Bermejo and Ana Figueiras 1 Introduction 173 2 Composition of Coal-Tars and Pitches 173 3 Characterization of Tars and Pitches 178

3.1 Global Characterization 179 3.2 Fractionation and Characterization of Fractions 187

4 Applications of Tars and Pitches 195 5 Future Trends 202 6 References 203

Chemistry and Properties of Coal-Tar and Petroleum Pitch Maximilian Zander 1 Introduction 205 2 Composition of Pitches 205

2.1 Coal-Таг Pitch 205 2.2 Petroleum Pitch 206

3 Characterization of Pitches 207 3.1 Characterization by Material Properties 207 3.2 Characterization by Structural Features 212 3.3 Determination of Individual Compounds occurring

XXK

in Pitches 230 4 Chemistry of Pitches 237

4.1 Carbonization Chemistry of Pitches 237 4.2 Other than Carbonization Chemistry of Pitches 250

5 References 252

Mesophase Pitch from Aromatic Hydrocarbons Isao Mochida, Seong-Ho Yoon, Yozo Korai, Koichi Kanno, Yukio Sakai and Makoto Komatsu 1 Introduction 259 2 Synthetic procedures of Mesophase Pitches 261

2.1 Conventional Preparation Methods 261 2.2 Novel Preparation Methods 262

3 Commercial Preparation of Aromatic Hydrocarbon Derived Mesophase Pitch 265

4 Structure of Mesophase Pitch 267 4.1 Molecular Basis 267 4.2 Molecular Assembly 270

5. General and Carbonization Properties of Mesophase Pitches 272 6 Properties of Mesophase Pitch as a Liquid Crystal 273 7 Spinning Characteristics of Mesophase Pitch 275 8 Thermal Stability and Oxidation Reactivity of

Mesophase Pitches and their Derived Fibers 278 9 Applications of Mesophase Pitches 280

9.1 Mesophase Pitch-Based Carbon Fiber 280 9.2 Other Novel Applications 281

10 References 282

Carbon Fibres and Active Carbon Fibers Seong-Ho Yoon, Yozo Korai and Isao Mochida 1 Introduction 287 2 History of Carbon Fibers 288 3 Production of Carbon Fibers 291

3.1 Carbon Fiber from Cellulose 293 3.2 Carbon Fiber from PAN 293 3.3 Carbon Fiber from Pitch Materials 295

4 Properties of Carbon Fibers 297 5 Correlations of Structure with Properties of Carbon Fibers 299 6 Synthesis of Precursors 302

6.1 Cellulose Precursor 302 6.2 PAN Precursor 303 6.3 Pitch Precursor 303

7 Properties of Precursors and their Spinning 305 7.1 PAN Precursor 305

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7.2 Pitch Precursor 305 8 Stabilization 308

8.1 PAN Precursor 308 8.2 Pitch Precursor 309

9 Carbonization and Graphitization 311 9.1 Carbonization of Cellulose Precursor 311 9.2 Carbonization of Stabilized PAN Precursor 313 9.3 Carbonization of Stabilized Pitch Precursor 314

10 Applications of Carbon Fibers 315 11 Active Carbon Fibers 316

11.1 Preparation of Active Carbon Fiber 316 11.2 Structural Characteristics 318 11.3 Adsorption Characteristics of Active Carbon Fiber 319 11.4 Applications of Active Carbon Fibers 321

12 Conclusions 321 13 References 322

9. Spinning of Carbon Fiber Precursors Dan D. Edie, John J. McHugh and James A. Newell 1 Introduction 327 2 Wet Spinning of PAN 330

2.1 Rheological Issues 332 2.2 Alternative Spinning Techniques 334

3 Spinning of High-Performance Polymers 334 4 Melt-Spinning of Mesophase Pitch 337

4.1 Flow behaviour of Mesophase 342 5 Fiber Heat Treatment 348 6 Summary 349 7 References 349

10. Physical Adsorption and Porosity in Carbons Harry Marsh and Maria-Antonia Diez Diaz- Estebanez 1 Introduction 353 2 Adsorbents and Adsorbates 354

2.1 SoUd Surfaces 354 2.2 Adsorbate Molecules 354

3 The Adsorption Process 355 4 Measuring Extents of Adsorption 358 5 Definitions: Adsorption Data 359 6 Interpretations of Adsorption Data 361 7 Surfaces Area: Fact or Fiction 366

7.1 Different Methodologies: Different Results 368 7.2 Significance of Surface Area 369 7.3 Definitions of Surface Area 372

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8 Porosity: What is it? 372 8.1 Structure in Carbons 374

9 References 377 10 Further Reading 377

11. Carbon Gasification Reactions Jacob A. Moulijn and Freek Kapteijn 1 2

3 4 5

6

7. 8

Introduction Towards a Unified Theory 2.1 Inhibition by Hydrogen 2.2 Temperature Ranges of Gasification Reactions Alkali Metal Catalysts Reactivity versus Burn-Off Results from Transient Kinetic Studies 5.1 Structure of Alkali Metal Catalysts under

Reaction Conditions Unified Mechanism 6.1 Reaction Rates Conclusions References

379 380 383 384 385 387 388

393 396 397 399 400

12. Oxidation Protection of Carbon Materials Douglas W. McKee 1 Introduction 403 2 Principles of Oxidation Protection 404

2.1 Active Site Poisoning 404 2.2 Matrix Inhibition in Carbon-Carbon Composites 411 2.3 Barrier Coatings 413 2.4 Multilayer Coatings and Hybrid Protection Systems 427

3 Conclusions 432 4 References 433

13. Chemi-Sorption Processes of Carbons Wesley P. Hoffman 1 Adsorption Processes 437

1.1 Introduction 437 1.2 Historical perspective 439 1.3 Differences between Physical and Chemical Adsorption 440

2 Chemisorption on Solids 442 2.1 Introduction 442 2.2 The Langmuir Isotherm 443 2.3 Failure of the Langmuir Isotherm 446 2 4 Times of Adsorption 448 2.5 Desorption 449

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2.6 Kinetics of Chemisorption 450 3 Chemisorption on Carbons 451

3.1 Characterization 451 3.2 Measurement Techniques 451 3.3 Early Work involving Chemisorption on Carbons 455 3.4 Chemisorption of Oxygen on Carbons 457 3.5 Concept of Reactive Surface Area 463 3.6 Characterization of Oxygen Functional Groups 465 3.7 Chemisorption of Hydrogen on Carbons 470 3.8 Chemisorption of Hydrocarbons on Carbons 471 3.9 Chemisorption of Halogens on Carbons 474 3.10 Chemisorption of other Molecules on Carbons 475 3.11 Processes that Benefit from Chemisorption 475

4 Conclusions 479 5 References 479

14. Mechanical Properties of Carbon Materials Robert H. Bradley 1 Introduction 485 2 Mechanical Properties of Materials 485

2.1 Fracture 485 2.2 Deformation and Elasticity 487 2.3 Elastic Behaviour 490 2.4 Plastic Behaviour 491

3 Carbon Materials 494 3.1 Carbon Fibre Reinforced Composites 495 3.2 Carbon Fibre Reinforced Plastics 496 3.3 Carbon-Carbon Composites 496 3.4 Particulate Reinforced Elastomers 497 3.5 Cokes 499

4 Mechanical Properties of Composite Materials 500 4.1 Interfacial Effects 500 4.2 Determination of Composite Mechanical Properties 505

5 Effects of Porosity on Mechanical Strength 507 6 References 509

15. Coal Combustion David E. Clarke 1 Introduction 511 2 Fundamentals of Pf Combustion in Utility Power Generation 512 3 Assessment of Coal Quality 513

3.1 Heating Value 514 3.2 Proximate Analysis 514 3.3 Ultimate Analysis 518

ХХХШ

3.4 Hardgrove Grindability Index 518 4 Coal Properties, Combustion Performance and on Plant Operation 519

4.1 Coal Storage, Handling and Milling 519 4.2 Combustion 521 4.3 Emissions 525 4.4 Ash Disposal 527

5 Modelling of Coal Quality Effect on Plant Performance 527 6 Conclusions 528 7 Acknowledgements 530 8 Further Reading 531

16. Petrography and Reflectance Microscopy Isabel Sudrez-Ruiz 1 Introduction 533 2 Coal Composition 533

2.1 The Microscopic Constituents of Coal 534 2.2 The Macroscopic Constituents of Coal 554

3 Petrographic Methods 557 3.1 Sampling 557 3.2 Preparation of Samples 558 3.3 Petrographic Analysis 558

4 Applications of Coal Petrology 565 5 References 566

17. Porosity in Coals Maria-Antonia Diez Diaz- Estebanez and Harry Marsh 1 2 3

4 5

6 7 8

Introduction Coal Origins Coalification 3.1 Coal Rank Coal - A Macromolecular System Coal as an Adsorbent 5.1 Adsorption Capacity 5.2 Activated Diffusion Effects 5.3 Coal Carbonization Coalbed Methane The Generation of Molecules of Water and Methane within Coal References and Further Reading

571 571 574 574 576 580 580 581 584 586 590 592

18. Chemistry of Production of Metallurgical Coke Ramon Alvarez and Maria-Antonia Diez Diaz- Estebanez 1 Introduction 595 2 The Coking Process 596 3 Physical and Chemical Aspects of the Coking Process 600

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3.1 Interpretation of the Plastic Properties of Coal 603 4 Criteria for Coking Coals and Coal Blending 605

4.1 Coking Tests 605 4.2 Plastic Properties of Coal 606

5 Coke Quality 609 5.1 Chemical Properties 609 5.2 Physical Properties 609 5.3 Coke Properties at High Temperatures 610 5.4 Resistance to Attack by Alkali 613 5.5 Significance of Optical Texture in Cokes 613

6 Coke Quality Prediction 614 6.1 Coke Strength Prediction 614 6.2 Prediction of CRI and CSR Indices 616

7 Coking Pressure 618 8 Coke Dry Quenching 622 9 Developments in Modern Coking Practice and Future Technology 624

9.1 Current Techniques in Coke Manufacture 624 9.2 Increase in Соке-Oven Dimensions 627 9.3 The Future in the Coking Industry 629

10 References 630 10.1 General References 630 10.2 Specific References 631

Catalysis of Coal Liquefaction Isao Mochida, Duayne Whitehurst and Kinya Sakanishi 1 Introduction 637

1.1 World Energy Demand 637 1.2 History of Coal Liquefaction 639 1.3 The Present Status of Coal Liquefaction 641 1.4 Cost of Coal Liquefaction 642

2 Fundamental Chemical and Catalytic Transformations During Coal Liquefaction 642

3 Stages of Coal Liquefaction 645 4 Key Reactions in Coal Liquefaction 646 5 Catalysis in the Liquefaction 648

5.1 Catalytic Species 648 5.2 Preparation 650 5.3 Chemical Functions of Catalysts 651 5.4 Type of Catalyst Usage 653 5.5 Design of Catalyst Recovery 654

6 Mechanisms of Catalytic Reactions Involved in Coal Liquefaction 654 7 The Roles of Solvent and Catalyst in the Primary Stages 656

7.1 Functions of Solvent and Catalyst in Coal Dissolution 656 7.2 Mechanisms of Regressive Reactions and Their Suppression 657

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7.3 Flow of Slurry Including Solid Catalysts 658 8 Catalytic Upgrading of Crude Coal Liquids in the Secondary Stage 658

8.1 Interface of Primary and Secondary Stages - Solid/Liquid Separations 659

8.2 Reaction and Roles of Catalysts in the Secondary Stage 659 8.3 The Quality of Coal Liquids as Fuels 662 8.4 Design of Step Schemes and Catalysts for the Secondary

Stage 662 9 References 662

Unit Conversions 669

Subject Index 671

XXXVI