Phase Equilibria in Chemical Engineering

Phase Equilibria in Chemical Engineering is devoted to the thermodynamic basis and practical aspects of the calculation of equilibrium conditions of multiple phases that are pertinent to chemical engineering processes. Efforts have been made throughout the book to provide guidance to adequate theory and practice. The book begins with a long chapter on equations of state, since it is intimately bound up with the development of thermodynamics. Following material on basic thermodynamics and nonidealities in terms of fugacities and activities, individual chapters are devoted to equilibria primarily between pairs of phases. A few topics that do not fit into these categories and for which the state of the art is not yet developed quantitatively have been relegated to a separate chapter. The chapter on chemical equilibria is pertinent since many processes involve simultaneous chemical and phase equilibria. Also included are chapters on the evaluation of enthalpy and entropy changes of nonideal substances and mixtures, and on experimental methods. This book is intended as a reference and self-study as well as a textbook either for full courses in phase equilibria or as a supplement to related courses in the chemical engineering curriculum. Practicing engineers concerned with separation technology and process design also may find the book useful.

List of Figures

List of Tables

List of Examples

Preface

A Guide for the Perplexed

1. Equations of State

1.1 Historical Notes

1.2 Nonideal Gases

1.3 Corresponding States

1.4 The Virial Equation

1.5 Cubic Equations

1.6 Complex Equations of State

1.7 Intermolecular Forces and Equations of State

1.8 The Critical State and Critical Properties

1.9 Comparisons and Tentative Recommendations

1.10 Review Literature on Equations of State

1.11 Problems

2. Thermodynamic Functions and Equilibrium

2.1 Energy Functions

2.2 Fundamental Equations

2.3 Total and Specific Properties

2.4 Partial Molai Properties

2.5 Derivatives with Respect to Mol Fractions

2.6 Homogeneous Functions

2.7 Variation of Properties with Temperature and Pressure

2.8 Mixing and Excess Functions

2.9 The Gibbs-Duhem Equation and Thermodynamic Consistency

2.10 Conditions of Equilibrium

2.11 Problems

3. Fugacity and Fugacity Coefficient

3.1 Definitions and Basic Relations

3.2 Pure Substances

3.3 Mixtures

3.4 Ideal Mixtures

3.5 Liquid and Solid Phases

3.6 Applications

3.7 Problems

4. Activity Coefficients

4.1 Activity and Activity Coefficients

4.2 Standard States

4.3 Thermodynamic Relations Involving Activity Coefficients

4.4 Determination of Activity Coefficients

4.5 Activity Coefficients and Equations of State

4.6 Correlation of Data

4.7 The Margules and Related Equations

4.8 The van Laar Equation

4.9 The Wilson Equation and Some Modifications

4.10 The NRTL (Renon) Equation

4.11 The UNIQUAC (Universal Quasi-Chemical) Equation

4.12 Multicomponent Mixtures

4.13 Comparison of Equations

4.14 Multiple Roots

4.15 Infinite Dilution

4.16 Activity Coefficients from Pure Component Properties

4.17 Activity Coefficients from Measurements of Equilibrium

4.18 The Effect of Temperature and Excess Enthalpy

4.19 Problems

5. Phase Diagrams

5.1 Geometric Representation

5.2 The Phase Rule

5.3 Unary Systems

5.4 Binary Systems

5.5 Ternary Systems

5.6 More than Three Components

5.7 Selected Books on Phase Diagrams

5.8 Problems

6. Vapor-Liquid Equilibrium

6.1 Vapor and Liquid Phases

6.2 Vaporization Equilibrium Ratio

6.3 Equilibria with Ks Independent of Composition

6.4 Equilibria with Äs Dependent on Composition

6.5 Solubility of Gases in Liquids

6.6 Binary VLE Diagrams

6.7 Gibbs Energy Minimization

6.8 Problems

7. Liquid-Liquid Equilibria

7.1 Liquid Mixtures

7.2 Phase Diagrams

7.3 Miscibility and Thermodynamic Stability

7.4 Binary Mixtures

7.5 Ternary and Multicomponent Mixtures

7.6 Prediction of LLE with UNIFAC or ASOG

7.7 Solubility of Liquids

7.8 Vapor-Liquid-Liquid Equilibria

7.9 Vapor-Liquid-Solid Equilibria

7.10 Problems

8. Liquid-Solid Equilibrium

8.1 Introduction

8.2 Solubility of Solids in Liquids

8.3 Melt Equilibria

8.4 Binary Mixtures

8.5 Multicomponent Systems

8.6 Solubility of Solids and Liquids in Supercritical Gases

8.7 Problems

9. Other Topics

9.1 Adsorption

9.2 Aqueous Electrolyte Systems

9.3 Undefined Compounds and Mixtures

9.4 Polymers

9.5 Liquid Crystals and Micelles

9.6 Mixtures at Supercritical Conditions

9.7 Hydrates

9.8 Problems

10. Chemical Equilibria

10.1 Introduction

10.2 The Degree of Advancement of a Chemical Reaction

10.3 The Equilibrium Equation

10.4 The Equilibrium Constant and Reference States

10.5 Equilibrium Composition

10.6 Multiple Reactions

10.7 Combined Chemical and Phase Equilibria

10.8 Problems

11. Evaluation of Changes in Enthalpy and Entropy

11.1 Basic Relations

11.2 Evaluation of Residual Properties

11.3 Specific Equations of State

11.4 Result of Changes in both P and T

11.5 Mixtures

11.6 Mixing of Liquids

11.7 Vaporization Enthalpy

11.8 Hydrocarbon Mixtures

11.9 Problems

12. Principles of Experimental Methods for Phase Equilibria

12.1 Solubility in Liquids

12.2 Boiling Point and Vapor Pressure

12.3 Vapor-Liquid Equilibrium

12.4 Liquid-Solid (Melt) Equilibrium

12.5 General References on Experimental Methods for Phase Equilibria

Appendixes

Appendix A General Thermodynamic Formulas

Appendix B Numerical Methods

Appendix C Computer Programs

Appendix D Physical Properties

Appendix E Parameters and Correlations

Appendix F Notation Index

Appendix G Units and Conversions

Appendix H References to the Literature

Substance Index

Subject Index