Page 13 - Elements of Chemical Reaction Engineering Ebook

xiv Contents

11.5. I Catalyst Regeneration 720
11.5.2 Dissolution of Monodispersed Solid Particles 724
11.5.3 Flow and Dissolution in Porous Media 726
Summary 728
Questions and Problems 729
Journal Article Problem 735
Journal Critique Problems 735
CD-ROM Material 735
Supplementary Reading 736

12 DIFFUSION AND REACTION IN POROUS CATALYSTS 738

12.1 Diffusion and Reaction in Spherical Catalyst Pellets 739
12.1.1 Effective Diffusivity 739
12.1.2 Derivation of the Differential Equation Describing
DifSusion and Reaction 741
12.1.3 Writing the Equation in Dimensionless Form 743
12.1.4 Solution to the Diflerential Equation
for a First-Order Reaction 746
12.2 Internal Effectiveness Factor 747
12.3 Falsified Kinetics 753
12.4 Overall Effectiveness Factor 755
12.5 Estimation of Diffusion- and Reaction-Limited Regimes 758
12.5. I Weisz-Prater Criterion for Internal Diffusion 758
12.5.2 Mears' Criterion for External Difision 761
12.6 Mass Transfer and Reaction in a Packed Bed 761
12.7 Determination of Limiting Situations
from Reaction Data 767
12.8 Multiphase Reactors 768
12.8.1 Slurry Reactors 769
12.8.2 Trickle Bed Reactors 783
12.9 Fluidized-Bed Reactorsc,,.RoM 786
12.10 The Overall View 787
12.1 1 Chemical Vapor Deposition Reactors 789
summary 793
Questions and Problems 795
Journal Article Problems 804
Journal Critique Problems 805
CD-ROM Material 805
Supplementary Reading 806

13 DISTRIBUTIONS OF RESIDENCE TIMES
FOR CHEMICAL REACTORS 809

13.1 General Characteristics 809
13.1.1 Residence-Erne Distribution Function 811