Chemical Engineering Thermodynamics II - CPP

1 Chemical Engineering Thermodynamics II (CHE 303 Course Notes) Nguyen Chemical and Materials Engineering Cal Poly Pomona (Winter 2009) Contents Chapter 1: Introduction Basic Definitions 1-1 Property 1-2 Units 1-3 Pressure 1-4

2 Temperature 1-6 Energy Balance 1-7 Example : Gas in a piston-cylinder system 1-8 Example : Heat Transfer through a tube 1-10 Chapter 2: Thermodynamic Property Relationships Type of Thermodynamic Properties 2-1 Example : Electrolysis of water 2-3 Example : Voltage of a hydrogen fuel cell 2-4 Fundamental Property Relations 2-5 Example : Finding the saturation pressure 2-8 Equations of State 2-11 The Virial Equation of State 2-11 Example : Estimate the tank pressure 2-12 The Van de Walls Equation of State 2-13 Example : Expansion work with Van de Walls EOS 2-15 Soave-Redlick-Kwong (SRK) Equation 2-17 Example.

3 Gas Pressure with SRK equation 2-17 Example : Volume calculation with SRK equation 2-18 Properties Evaluations 2-21 Example : Exhaust temperature of a turbine 2-21 Example : Change in temperature with respect to pressure 2-24 Example : Estimation of thermodynamic property 2-26 Example : Heat required to heat a gas 2-27 Chapter 3: Phase Equilibria Phase and Pure Substance 3-1 Phase Behavior 3-4 Example.

4 Specific volume from data 3-7 Introduction to Phase Equilibrium 3-11 Pure Species Phase Equilibrium 3-12 Gibbs Free Energy as a Criterion for Chemical Equilibrium 3-12 The Chemical Potential 3-13 Vapor Liquid Phase Equilibrium 3-16 Example : Horsepower of a compressor 3-18 Example : Two-level refrigeration system 3-19 The Clapeyron Equation 3-23 Example : Triple point estimation 3-27 Refrigeration 3-30 i Example : A vapor compression refrigeration cycle 3-31 Example : A refrigeration cycle using refrigerant 134a 3-32 Example : A refrigeration cycle using refrigerant 134a 3-34 Example : A refrigeration cycle with nonideal compressor 3-35 Partial Molar Properties 3-36 Example : Partial molar volume 3-37 Example : Enthalpy of mixing 3-38 Example : Enthalpy-concentration chart 3-39 Chapter 4: Principle of Phase Equilibrium II The Phase Rule 4-1 Example : The degree of freedom 4-1 Example.

5 Degree of freedom for vapor-liquid equilibrium 4-2 The Fugacity 4-3 Example : Fugacity of liquid water 4-5 Example : Fugacity using Van der Waals EOS 4-6 Example : Fugacity of steam 4-10 Example : Change in Gibbs energy 4-11 Fugacity of Species i in a Gas Mixture 4-15 Example : Fugacity using Peng-Robinson EOS 4-17 Fugacity in the Liquid Phase 4-19:20 Chapter 5: Applied Phase Equilibrium Vapor-Liquid Equilibrium for Ideal Systems 5-1 Example : Bubble point temperature calculation 5-3 Example : Bubble point pressure calculation 5-5 Example : Dew point temperature calculation 5-6 Example : Dew point pressure calculation 5-8 Example : Txy diagram for benzene-toluene mixture 5-9 Example : Dew point pressure using K-values 5-11 Isothermal Flash Calculation Using K-values 5-15 Example : Isothermal flash with V/F specified 5-18 Example.

6 Isothermal flash with T specified 5-20 Vapor-Liquid Equilibrium with Non-ideal Liquid 5-23 Example : Bubble point pressure with Van Laar model 5-25 Example : Bubble point temperature with Wilson model 5-26 Example : Dew point temperature with Wilson model 5-28 Example : Txy diagram with Wilson model 5-31 Fitting Activity Coefficient Models with VLE Data 5-35 Example : Evaluation of Margules and Van Laar parameters 5-37 Example : Evaluation of Wilson parameters 5-43 Azeotropes 5-45 Example : Evaluation of Wilson parameters 5-50 Estimation of Activity Coefficients 5-52 Example : Acetone mole fraction in a system with air 5-52 Example : Solubility of ethane in n-heptanol 5-54 Phase Behavior in Partially Miscible Systems 5-55 ii Example : Liquid mixture in two separate phases 5-56 Example : Liquid mixture in a single phase 5-56 Example : LLE for a binary mixture 5-61 Vapor-Liquid-Liquid Equilibrium: VLLE 5-63 Example.

7 Composition and pressure for a VLLE system 5-64 Example : VLLE calculations 5-66 Example : VLLE estimation 5-68 Example : VLLE for water and hydrocarbon 5-71 The Thermodynamics of Osmosis 5-73 Example : Estimation of the PVC molecular weight 5-76 Example : Dissociation of NaCl molecules 5-78 Distribution of a Solute Between Liquid Phases 5-79 Solubility of a Solid in a Liquid Phase 5-79 Example : Solubility of a Drug 5-81 Distribution of a Solute Between Liquid Phases 5-84 Example : Drug Extraction from the Aqueous Phase 5-87 Example : Purification of an Antibiotic 5-88 Single-Stage Equilibrium Extraction 5-89 Example : Drug Extraction from the Aqueous Stream 5-90:91 Chapter 6: Chemical Equilibrium Introduction 6-1 Example : Extent of reaction and fractional conversion 6-2 Example : Time to reach 90% conversion in a batch reactor 6-5 Chemical Reaction and Gibbs Energy 6-6 The Condition of Equilibrium for a Chemical Reaction 6-9 Calculation of Equilibrium Constant from Data 6-11 Example : Equilibrium constant for methanol reaction 6-11 Example : Equilibrium constant for nitrogen oxide 6-12 Variation of Equilibrium Constant with Temperature 6-14 Example : Methanol reaction at 60oC 6-17 Example.

8 Pyrolysis of methanol 6-18 Homogeneous Gas Phase Reaction 6-20 Example : Decomposition of Ethane 6-21 Example : Partial pressure of monatomic hydrogen 6-23 Heterogeneous Reaction 6-30 Example : Activity of water 6-31 Example : Equilibrium conversion for isomerization 6-32 Example : Dissociation of CaCO3(s) 6-33 Thermodynamics of Pack Cementation 6-34 Equilibrium in Electrochemical Systems 6-37 Example : Copper etching 6-40 Complex Chemical Equilibrium 6-41 Example : Number of independent reactions 6-42 Example : Number of independent reactions 6-43 iii ivAppendix Appendix A: Solving Algebraic Equations The Newton-Raphson Method A-1 Example : Newton-Raphson method for a root in [1, 2] A-2 Newton s Method for Systems of Nonlinear Algebraic Equations A-3 Example : Newton method for 3 nonlinear equations A-4 Solving set of nonlinear equations with Excel A-6 Appendix B: Curve Fitting Nonlinear Curve Fitting B-1 Example : Fit the function T(t.)

9 , h) = (1 e ht) to the data B-4 Appendix C: Process Simulator (Provision) Appendix D: Previous Exams Quiz 1 D-1 Quiz 2 D-3 Quiz 3 D-7 Quiz 4 D-9 Quiz 5 D-12 Answer to Quizzes 1-1 Chapter 1 Introduction Basic Definitions Thermodynamics is the science that seeks to predict the amount of energy needed to bring about a change of state of a system from one equilibrium state to another. While Thermodynamics tells us nothing about the mechanisms of energy transfer, rates of change, and time associated with a system changing from one equilibrium state to another, it is still the lynch-pin that allow us to answer these questions.

10 Definition of 'heat': Heat is energy in transit solely as a result of a temperature difference. Definition of 'work': Work is energy exchange between system and surroundings due to any phenomenon except a temperature difference. Definition of 'temperature': Temperature is a measure of the mean kinetic energy of molecules. Absolute zero (0oK) is a state of c