Introduction to Chemical Engineering Kinetics and Reactor Design

CHARLES G. HILL, JR., SC.D, is Professor Emeritus at the University of Wisconsin–Madison with over 200 peer-reviewed publications to his credit. In addition to his academic work, he has served as a consultant to government agencies and private corporations. Dr. Hill’s research has been highly interdisciplinary, including experience as a Fulbright Senior Scholar collaborating on studies of enzymatic reactions at the Institute for Catalysis and Petrochemistry (Spain). THATCHER W. ROOT, PHD, is Professor of Chemical Engineering at the University of Wisconsin–Madison. Dr. Root was awarded an NSF Presidential Young Investigator Award and recently received the Benjamin Smith Reynolds Award for Excellence in Teaching Engineers.

Preface ix

Preface to the First Edition xi

1. Stoichiometric Coefficients and Reaction Progress Variables 1

1.0 Introduction 1

1.1 Basic Stoichiometric Concepts 2

Literature Citation 3

2. Thermodynamics of Chemical Reactions 4

2.0 Introduction 4

2.1 Chemical Potentials and Standard States 4

2.2 Energy Effects Associated with Chemical Reactions 5

2.3 Sources of Thermochemical Data 7

2.4 The Equilibrium Constant and its Relation to ΔG0 7

2.5 Effects of Temperature and Pressure Changes on the Equilibrium Constant 8

2.6 Determination of Equilibrium Compositions 9

2.7 Effects of Reaction Conditions on Equilibrium Yields 11

2.8 Heterogeneous Reactions 12

2.9 Equilibrium Treatment of Simultaneous Reactions 12

2.10 Supplementary Reading References 15

Literature Citations 15

Problems 15

3. Basic Concepts in Chemical Kinetics: Determination of the Reaction Rate Expression 22

3.0 Introduction 22

3.1 Mathematical Characterization of Simple Reaction Systems 25

3.2 Experimental Aspects of Kinetic Studies 29

3.3 Techniques for the Interpretation of Kinetic Data 34

Literature Citations 53

Problems 54

4. Basic Concepts in Chemical Kinetics: Molecular Interpretations of Kinetic Phenomena 72

4.0 Introduction 72

4.1 Reaction Mechanisms 73

4.2 Chain Reactions 83

4.3 Molecular Theories of Chemical Kinetics 93

Literature Citations 103

Problems 104

5. Chemical Systems Involving Multiple Reactions 117

5.0 Introduction 117

5.1 Reversible Reactions 117

5.2 Parallel or Competitive Reactions 125

5.3 Series or Consecutive Reactions: Irreversible Series Reactions 133

5.4 Complex Reactions 137

Literature Citations 142

Problems 142

6. Elements of Heterogeneous Catalysis 152

6.0 Introduction 152

6.1 Adsorption Phenomena 153

6.2 Adsorption Isotherms 156

6.3 Reaction Rate Expressions for Heterogeneous Catalytic Reactions 160

6.4 Physical Characterization of Heterogeneous Catalysts 170

6.5 Catalyst Preparation, Fabrication, and Activation 174

6.6 Poisoning and Deactivation of Catalysts 177

Literature Citations 178

Problems 179

7. Liquid Phase Reactions 189

7.0 Introduction 189

7.1 Electrostatic Effects in Liquid Solution 191

7.2 Pressure Effects on Reactions in Liquid Solution 192

7.3 Homogeneous Catalysis in Liquid Solution 193

7.4 Correlation Methods for Kinetic Data: Linear Free Energy Relations 202

Literature Citations 207

Problems 207

8. Basic Concepts in Reactor Design and Ideal Reactor Models 216

8.0 Introduction 216

8.1 Design Analysis for Batch Reactors 225

8.2 Design of Tubular Reactors 228

8.3 Continuous Flow Stirred-Tank Reactors 234

8.4 Reactor Networks Composed of Combinations of Ideal Continuous Flow Stirred-Tank Reactors and Plug Flow Reactors 254

8.5 Summary of Fundamental Design Relations: Comparison of Isothermal Stirred-Tank and Plug Flow Reactors 256

8.6 Semibatch or Semiflow Reactors 256

Literature Citations 259

Problems 259

9. Selectivity and Optimization Considerations in the Design of Isothermal Reactors 273

9.0 Introduction 273

9.1 Competitive (Parallel) Reactions 274

9.2 Consecutive (Series) Reactions: A →k1→ B →k2→ C →k3→ D 278

9.3 Competitive Consecutive Reactions 283

9.4 Reactor Design for Autocatalytic Reactions 290

Literature Citations 294

Problems 294

10. Temperature and Energy Effects in Chemical Reactors 305

10.0 Introduction 305

10.1 The Energy Balance as Applied to Chemical Reactors 305

10.2 The Ideal Well-Stirred Batch Reactor 307

10.3 The Ideal Continuous Flow Stirred-Tank Reactor 311

10.4 Temperature and Energy Considerations in Tubular Reactors 314

10.5 Autothermal Operation of Reactors 317

10.6 Stable Operating Conditions in Stirred Tank Reactors 320

10.7 Selection of Optimum Reactor Temperature Profiles: Thermodynamic and Selectivity Considerations 324

Literature Citations 327

Problems 328

11. Deviations from Ideal Flow Conditions 337

11.0 Introduction 337

11.1 Residence Time Distribution Functions, F(t) and dF(t) 337

11.2 Conversion Levels in Nonideal Flow Reactors 352

11.3 General Comments and Rules of Thumb 358

Literature Citations 359

Problems 359

12. Reactor Design for Heterogeneous Catalytic Reactions 371

12.0 Introduction 371

12.1 Commercially Significant Types of Heterogeneous Catalytic Reactors 371

12.2 Mass Transport Processes within Porous Catalysts 376

12.3 Diffusion and Reaction in Porous Catalysts 380

12.4 Mass Transfer Between the Bulk Fluid and External Surfaces of Solid Catalysts 406

12.5 Heat Transfer Between the Bulk Fluid and External Surfaces of Solid Catalysts 413

12.6 Global Reaction Rates 416

12.7 Design of Fixed Bed Reactors 418

12.8 Design of Fluidized Bed Catalytic Reactors 437

Literature Citations 439

Problems 441

13. Basic and Applied Aspects of Biochemical Transformations and Bioreactors 451

13.0 Introduction 451

13.1 Growth Cycles of Microorganisms: Batch Operation of Bioreactors 452

13.2 Principles and Special Considerations for Bioreactor Design 472

13.3 Commercial Scale Applications of Bioreactors in Chemical and Environmental Engineering 495

Literature Citations 516

Problems 517

Appendix A. Fugacity Coefficient Chart 527

Appendix B. Nomenclature 528

Appendix C. Supplementary References 535

Author Index 537

Subject Index 545