Catalyst Design: Optimal Distribution of Catalyst in Pellets, Reactors, and Membranes

by Massimo Morbidelli , Asterios Gavriilidis , Arvind Varma

• ISBN13: 9780521660594
• ISBN10: 0521660599
• Edition: 1st
• Format: Hardcover
• Copyright: 2001-02-26
• Publisher: Cambridge University Press

Summary

Heterogeneous catalysis is widely used in chemical, refinery, and pollution-control processes. For this reason, achieving optimal performance of catalysts is a significant issue for chemical engineers and chemists. This book addresses the question of how catalytic material should be distributed inside a porous support in order to obtain optimal performance. It treats single and multiple reaction systems, isothermal and nonisothermal conditions, pellets, monoliths, fixed-bed reactors, and membrane reactors. The effects of physicochemical and operating parameters are analyzed to gain insight into the underlying phenomena governing the performance of optimally designed catalysts. Throughout, the authors offer a balanced treatment of theory and experiment. Particular attention is given to problems of commercial importance. With its thorough treatment of the design, preparation, and utilization of supported catalysts, this book will be an ideal resource for graduate students, researchers, and practising engineers and chemists.

Table of Contents

Preface	xiii
Introduction	1	(5)
Importance of Catalysis	1	(1)
Nonuniform Catalyst Distributions	1	(3)
Overview of Book Contents	4	(2)
Optimization of the Catalyst Distribution in a Single Pellet	6	(63)
The Case of a Single Reaction	6	(19)
Isothermal Conditions	6	(9)
Nonisothermal Conditions	15	(3)
Arbitrary Kinetics with External Transport Resistances	18	(5)
Dynamic Behavior	23	(2)
Multiple Reactions	25	(5)
Isothermal Conditions	25	(3)
Nonisothermal Conditions	28	(2)
The General Case of a Complex Reaction System	30	(10)
An Illustrative Example	31	(4)
General Reaction System	35	(5)
Catalyst Dispersion Considerations	40	(6)
Factors Affecting Catalyst Dispersion	40	(3)
Dependence of Catalytic Surface Area on Catalyst Loading	43	(3)
Optimal Distribution of Catalyst Loading	46	(17)
The Problem Formulation	47	(4)
A Single First-Order Isothermal Reaction	51	(3)
Linear Dependence between the Active Element Surface Area and Its Loading	54	(1)
First-Order Nonisothermal Reactions: Numerical Optimization	55	(4)
Multistep Optimal Loading Distribution	59	(4)
Experimental Studies	63	(6)
Oxidation Reactions	63	(3)
Hydrogenation Reactions	66	(2)
Fischer-Tropsch Synthesis	68	(1)
Optimization of the Catalyst Distribution in a Reactor	69	(17)
A Single Reaction	69	(8)
Isothermal Conditions	69	(6)
Nonisothermal Conditions	75	(2)
Multiple Reactions	77	(6)
Isothermal Conditions	79	(1)
Nonisothermal Conditions	79	(4)
Experimental Studies	83	(3)
Propane and CO Oxidation	83	(2)
Catalytic Incineration of Volatile Organic Compounds	85	(1)
Studies Involving Catalyst Deactivation	86	(9)
Nonselective Poisoning	86	(3)
Selective Poisoning	89	(2)
Experimental Studies	91	(4)
Methanation	91	(1)
Hydrogenation	92	(2)
NO Reduction	94	(1)
Membrane Reactors	95	(15)
Membrane Reactors with Nonuniform Catalyst Distribution	95	(5)
Optimal Catalyst Distribution in Pellets for an Inert Membrane Reactor	100	(1)
Optimal Catalyst Distribution in a Catalytic Membrane Reactor	100	(2)
Experimental Studies	102	(8)
Dehydrogenation Reactions	102	(3)
Preparation of Catalytic Membranes	105	(5)
Special Topics of Commercial Importance	110	(21)
Automotive Exhaust Catalysts	110	(5)
Design of Layered Catalysts	111	(2)
Nonuniform Axial Catalyst Distribution	113	(2)
Hydrotreating Catalysts	115	(4)
Composite Zeolite Catalysts	119	(2)
Immobilized Biocatalysts	121	(3)
Functionalized Polymer Resins	124	(7)
Preparation of Nonuniformly Functionalized Resin Particles	124	(2)
Applications to Reacting Systems	126	(5)
Preparation of Pellets with Nonuniform Distribution of Catalyst	131	(50)
Adsorption on Powders	132	(17)
Adsorption Isotherm Models	132	(3)
Effect of Impregnation Variables on Adsorption	135	(1)
Solution pH and Nature of Support	135	(3)
Surface Heterogeneity	138	(2)
Ionic Strength	140	(1)
Precursor Speciation	140	(2)
Coimpregnants	142	(2)
Nature of the Solvent	144	(1)
Surface Ionization Models	144	(1)
Constant-Capacitance Model	145	(1)
Diffuse-Layer Model	146	(1)
Basic Stern Model	147	(1)
Triple-Layer Model	147	(2)
Four-Layer model	149	(1)
Simultaneous Diffusion and Adsorption in Pellets	149	(32)
Theoretical Studies	150	(1)
Dry Impregnation	150	(3)
Wet Impregnation	153	(3)
Effects of Electrokinetic and Ionic Dissociation Phenomena	156	(1)
Effect of Drying Conditions	156	(2)
Experimental Studies	158	(1)
Single-Component Impregnation	159	(2)
Multicomponent Impregnation	161	(4)
Effects of Drying	165	(4)
Determination of Catalyst Distribution	169	(1)
Comparison of Model Calculations with Experimental Studies	169	(1)
Dry Impregnation	169	(2)
Wet Impregnation	171	(10)
Appendix A: Application of the Maximum Principle for Optimization of a Catalyst Distribution	181	(7)
Appendix B: Optimal Catalyst Distribution in Pellets for an Inert Membrane Reactor: Problem Formulation	188	(7)
B.1 The Mass and Energy Balance Equations	188	(3)
B.2 The Performance Indexes	191	(1)
B.3 Development of the Hamiltonian	192	(3)
Notation	195	(6)
References	201	(20)
Author Index	221	(4)
Subject Index	225