Page 8 - Separation process principles 2

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NRTLModel 55
UNIQUAC Model 56
UNIFAC Model 57
Liquid-Liquid Equilibria 58
2.7 Difficult Mixtures 58
Predictive Soave-Redlich-Kwong (PSRK) Model 59
Electrolyte Solution Models 59
Polymer Solution Models 59
2.8 Selecting an Appropriate Model 59
Summary 60 References 60 Exercises 61

Chapter 3 Mass Transfer and Diffusion 66
3.0 Instructional Objectives 67
3.1 Steady-State, Ordinary Molecular Diffusion 67
Fick's Law of Diffusion 68
Velocities in Mass Transfer 68
Equimolar Counterdiffusion 69
Unimolecular Diffusion 70
3.2 Diffusion Coefficients 72
Diffusivity in Gas Mixtures 72
Diffusivity in Liquid Mixtures 74
Diffusivities of Electrolytes 77
Diffusivity of Biological Solutes in Liquids 78
Diffusivity in Solids 78
3.3 One-Dimensional, Steady-State and Unsteady-State, Molecular Diffusion
Through Stationary Media 84
Steady State 84
Unsteady State 85
3.4 Molecular Diffusion in Laminar Flow 90
Falling Liquid Film 90
Boundary-Layer Flow on a Flat Plate 93
Fully Developed Flow in a Straight, Circular Tube 95
3.5 Mass Transfer in Turbulent Flow 97
Reynolds Analogy 99
Chilton-Colburn Analogy 99
Other Analogies 100
Theoretical Analogy of Churchill and Zajic 100
3.6 Models for Mass Transfer at a Fluid-Fluid Interface 103
Film Theory 103
Penetration Theory 104
Surface-Renewal Theory 105
Film-Penetration Theory 106
3.7 Two-Film Theory and Overall Mass-Transfer Coefficients 107
Gas-Liquid Case 107
Liquid-Liquid Case 109
Case of Large Driving Forces for Mass Transfer 109
Summary 11 1 References 112 Exercises 113