Selective Oxidation by Heterogeneous Catalysis

by Centi, G.; Cavani, Fabrizio; Trifiro, Ferrucio

• ISBN13: 9780306462658
• ISBN10: 0306462656
• Format: Hardcover
• Copyright: 2000-11-01
• Publisher: Plenum Pub Corp

Summary

Selective Oxidation by Heterogeneous Catalysis covers one of the major areas of industrial petrochemical production, outlining open questions and new opportunities. It gives keys for the interpretation and analysis of data and design of new catalysts and reactions, and provides guidelines for future research. A distinctive feature of this book is the use of concept by example. Rather than reporting an overview of the literature results, the authors have selected some representative examples, the in-depth analysis of which makes it possible to clarify the fundamental, but new concepts necessary for a better understanding of the new opportunities in this field and the design of new catalysts or catalytic reactions. Attention is given not only to the catalyst itself, but also to the use of the catalyst inside the process, thus evidencing the relationship between catalyst design and engineering aspects of the process. This book provides suggestions for new innovative directions of research and indications on how to reconsider the field of selective oxidation from different perspectives, outlining that is not a mature field of research, but that new important breakthroughs can be derived from fundamental and applied research. Suggestions are offered on how to use less conventional approaches in terms of both catalyst design and analysis of the data.

Author Biography

Fabrizio Cavani is Professor in charge of Industrial Chemistry at the University of Bologna, Italy.

Table of Contents

Trends and Outlook in selective Oxidation: and Introduction
Introduction	1	(4)
Technological and Industrial Developments	5	(8)
New Raw Materials	5	(3)
Conversion of Air-Based to Oxygen-Based Processes	8	(2)
Fine-Tuning Existing Oxidation Processes	10	(2)
Reducing the Number of Process Steps	12	(1)
New Opportunities Derived from Basic Research	13	(2)
The Ecological Issue as a Driving Force	15	(4)
Reduction or Elimination of Corpoducts	15	(1)
Synthesis of Propene Oxide	16	(1)
Synthesis of Cyclohexanone Oxime	16	(1)
Synthesis of Methyl Methacrylate	17	(1)
Use of Alternative Catalysts	17	(2)
Heterogeneous Versus Homogeneous Catalysis in Selective Oxidation	19	(6)
References	22	(3)
New Technological and Industrial Opportunities: Options
Use of Alternative Raw Materials	25	(12)
Alkanes as Raw Materials for Selective Oxidation Reactions	25	(1)
Advantages and Targets in Using and Alkane Feedstock	26	(3)
Key Questions in Alkane Functionalization	29	(1)
Processes of Industrial Interest Using an Alkane Feedstock	30	(2)
New Oxidants	32	(1)
Nitrous Oxide	33	(2)
Ozone	35	(1)
In Situ Generated Oxidants in the Liquid Phase	35	(2)
New Reactor Technology Options	37	(30)
Fixed-Bed Reactors	38	(1)
The Problem of Hot Spots in Both the Axial and Radial Directions	38	(1)
Heat and Mass Gradients	39	(4)
Presence of Multiple Steady States and Runaway Phenomena	43	(2)
Wide-Residence Time Distribution	45	(1)
High Pressure Drop	45	(1)
Technologies Designed to Overcome Drawbacks of Fixed-Bed Reactors	46	(1)
Dual-Bed Reactors	46	(1)
Distributed Inlet of One Reactant	46	(1)
Periodic Flow Reversal	47	(1)
Decoupling of the Exothermal Reaction into Two Steps	48	(1)
Integration of Exothermal and Endothermal Processes	49	(1)
Radial Flow Reactors	49	(1)
Fluidized-Bed Reactors	49	(4)
High-Gas-Velocity Systems: Circulating Fluidized-Bed Reactors	53	(3)
Structured Catalysts and Reactors	56	(4)
Monolith Reactors	60	(3)
Membrane Reactors	63	(2)
Electrochemical Cells as Reactors	65	(2)
Air Versus Oxygen Processes	67	(18)
Advantages in the Use of Oxygen Instead of Air in Industrial Oxidation Processes	67	(2)
Synthesis of Ethene Epolxide	69	(2)
Synthesis of 1,2-Dichloroethane (DCE)	71	(2)
Use of Pure Oxygen in the Oxidation of Alkanes	73	(1)
References	74	(11)
New Technological and Industrial Opportunities: Examples
Introduction	85	(2)
Examples of Opportunities for New Oxidation Processes	87	(33)
Selective Oxidation for Fine Chemicals and Pharmaceuticals	87	(1)
Oxidation with Hydrogen Peroxide and Organic Peroxide	87	(4)
Oxidation with Molecular Oxygen and Noble Metal-Based Catalysts	91	(4)
Bioinorganic-Type Oxidation	95	(5)
New Catalytic Processes for Bulk Chemicals Using Hydrogen Peroxide	100	(1)
Alkene Epoxidation Reactions	101	(8)
Cyclothexanone Ammoximation	109	(6)
Hydroxylation of Phenols	115	(5)
Examples of New Catalytic Systems	120	(12)
Metalloporphyrin Complexes	122	(2)
Polyoxometallates	124	(1)
Supported Metals	125	(1)
Isomorphically Substituted Molecular Sieves	126	(1)
Redox Pillared Clays	127	(1)
Phase-Transfer Catalysts	128	(1)
Guest Oxide Nanoparticles within Host Zeo-Type Materials	129	(3)
Conclusions	132	(9)
References	132	(9)
Control of the Surface Reactivity of Solid Catalysts: Industrial Processes of Alkane Oxidation
Introduction	141	(2)
Maleic Anhydride from n-Butane on Vanadium/Phosphorus Oxides	143	(28)
Industrial Processes of Maleic Anhydride Synthesis from n-Butane	143	(2)
Gas Phase Composition	145	(1)
Reactor Technologies	146	(2)
Catalyst Formulation	148	(3)
V/P Oxide Catalysts Synthesis and Characteristics	151	(1)
Role of the Precursor Phase	151	(2)
Activation and Conditioning Procedure	153	(3)
Role of the P/V Ratio and Catalyst Redox Properties	156	(1)
Role of Promoters	157	(1)
Structure of the V/P Oxide Phases	158	(3)
Advanced Aspects toward Understanding the Catalytic Chemistry of V/P Oxides	161	(1)
Role of Catalyst Microstructure and Topology	161	(5)
In Situ Surface Restructuring of VPO Catalysts	166	(2)
Catalyst Properties and Reactor/Process Configuration	168	(2)
Microkinetics of the Surface Transformations on V/P Oxide Catalysts	170	(1)
Alkane Versus Alkene Oxidation	170	(1)
Propane Ammoxidation to Acrylonitrile on Vanadium/Antimony Oxides	171	(32)
Background on the Direct Synthesis of Acrylonitrile from Propane	171	(2)
Role of Nonstoichiometry and Rutile Structure in V/Sb Oxide Catalysts	173	(2)
Comparison with Other Sb-Rich Rutilelike Mixed Oxide Catalysts	175	(1)
Nature of the Phases Present	176	(1)
Nonstoichiometry of Vanadium Antimonate and Catalytic Reactivity	177	(5)
Nonstoichiometry of Vanadium Antimonate and Surface Characteristics	182	(2)
Role of Microstructure	184	(1)
Surface Reaction Network as a Tool for Understanding and Controlling Reactivity	185	(1)
The Surface Reaction Network in Propane Ammoxidation over V/Sb Oxide Catalysts	186	(1)
The Surface Reaction Network as A Tool For Understanding the Surface Reactivity	187	(3)
Designing Better Catalysts	190	(1)
Conclusions	191	(1)
References	192	(11)
Control of the Surface Reactivity of Solid Catalysts: New Alkane Oxidation Reactions
Introduction	203	(1)
Oxidative Dehydrogenation of Alkanes	204	(37)
Dehydrogenation versus Oxidative Dehydrogenation	204	(3)
Constraints in Oxidative Dehydrogenation	207	(7)
Class of Catalysts Active in Oxidative-Dehydrogenation	214	(1)
Alkali and Alkaline Earth-Based Catalysts	215	(5)
Catalysts Based on Transition Metal Oxides	220	(6)
Catalysts and Reaction Mechanisms	226	(4)
Role of the Nature of the Alkane	230	(9)
Conclusions	239	(2)
New Types of Oxidation of Light Alkanes	241	(44)
Introduction	241	(2)
Ethane Conversion	243	(1)
Catalysts for Acetaldehyde and Acetic Acid Formation	243	(3)
Alternative Approaches for Catalyst Design	246	(3)
A New Route: Ethane Ammoxidation	249	(4)
Propane Conversion	253	(1)
Acrolein Synthesis	253	(3)
Acrylic Acid Synthesis	256	(3)
Isobutane Conversion to Methacrolein and Methacrylic Acid	259	(7)
n-Pentane Conversion to Maleic and Phthalic Anhydrides	266	(5)
Cyclohexane (Amm) oxidation	271	(1)
References	272	(13)
New Fields of Application For Solid Catalysts
Introduction	285	(2)
Selective Oxidation in the Liquid Phase with Solid Micro-or Mesoporous Materials	287	(13)
Framework Substitution	289	(1)
Synthesis, Characteristics, and Reactivity of Titanium Silicalite	290	(1)
Reactivity	290	(1)
Synthesis	291	(2)
Characterization	293	(1)
Nature of Active Species	294	(4)
Encapsulated Metal Complexes	298	(1)
Grafting or Tethering of Metal Complexes	298	(1)
New ``Hydrophobic'' Catalytic Materials for Liquid Phase Epoxidation of Alkanes	299	(1)
Heteropoly Compounds as Molecular-Type Catalysts	300	(10)
Introduction	300	(1)
Redox Properties of HPCs	301	(2)
Liquid Phase Oxidation	303	(1)
Oxidation with Molecular Oxygen	303	(2)
Oxidation with Hydrogen Peroxide, with Organic Peroxides or Other Monoxygen Donors	305	(4)
Gas Phase Oxidation: General Aspects	309	(1)
Solid Wacker-Type Catalysts	310	(15)
Palladium Supported on Monolayer-Type Redox Oxides	311	(2)
Solid Palladium-Heteropoly Compounds	313	(1)
Heterogenization of Wacker Catalysts in Microporous Materials	314	(1)
References	315	(10)
New Concepts and New Strategies in Selective Oxidation
Introduction	325	(1)
Selective Oxidation at Near Room Temperature Using Molecular Oxygen	326	(14)
Electrochemical Activation of Molecular Oxygen	327	(1)
Benzene to Phenol	328	(2)
Alkane Oxidation	330	(1)
π-Allyl and Wacker Oxidation of Alkenes	331	(3)
Activation of Molecular Oxygen by Spontaneous Charge Transfer from a Hydrocarbon	334	(2)
Oxidation of Alkenes	336	(1)
Oxidation of Alkylaromatics	337	(1)
Oxidation of Alkanes	337	(2)
Singlet Molecular Oxygen	339	(1)
New Approaches to Generate Active Oxygen Species	340	(10)
In Situ Generation of Monoxygen Donors	340	(1)
Methods of in Situ Generation of H2O2	341	(3)
Oxidation Reactions with in Situ Generated Hydrogen Peroxide	344	(1)
Generation of Active Oxygen Species by Ozone	345	(1)
Use of Nitrous Oxide as a Selective Oxidant	345	(1)
Reactivity of α-Oxygen	346	(2)
Use of Waste Nitrous Oxide Streams: Adipic Acid Production	348	(2)
Novel Reaction Mediums	350	(6)
Oxidations Reaction at Thin Supported Liquid Films	350	(1)
Heterogeneous Wacker-Type Catalysts	350	(2)
Ethene Acetoxylation to Vinyl Acetate	352	(2)
Other Cases	354	(1)
Oxidation Reaction under Supercritical Conditions	355	(1)
Conclusions	356	(7)
References	357	(6)
New Aspects of the Mechanisms of Selective Oxidation and Structure/Activity Relationships
Introduction	363	(6)
Outline and Scope of this Chapter	363	(1)
The Established Approach to Modeling Reaction Mechanisms at Oxide Surfaces	364	(5)
Active Sites or ``Living Active Surface''?	369	(17)
The Mechanism of Propene (Amm) oxidation	369	(1)
Analysis of the Model of the Mechanism of Propene (Amm) oxidation	370	(2)
Toward a Model of ``Living Active Surface'' Rather than Localized Catalysis at Active Sites	372	(3)
The Question of Stepwise Reaction Mechanisms	375	(1)
The Geometrical Approach to Oxidation Catalysis at Oxide Surfaces	376	(3)
The Question of Reaction at a Single ``Ensemble'' Site	379	(2)
The Role of Catalyst Reduction and Dynamics of Reaction	381	(3)
General Conclusions on the Modeling Approach to Selective Oxidation Catalysis	384	(2)
Surface Oxygen Species and Their Role in Selective Oxidation	386	(27)
Nature of the Interaction between Molecular Oxygen and Oxide Surfaces and Types of Oxygen Adspecies	388	(1)
Neutral Dioxygen Species	389	(1)
Charged Dioxygen Species	390	(2)
Monoxygen Species	392	(3)
Reactivity of Adsorbed Oxygen Species	395	(3)
New Aspects of the Reactivity of Surface Oxygen Species	398	(15)
Modification of the Surface Reactivity by Chemisorbed Species	413	(12)
The Role of Alkenes in the Self-Modification of the Surface Reactivity	414	(4)
The Role of the Nature of Intermediate Products	418	(2)
Chemisorption and Change in the Surface Pathways of Transformation	420	(2)
Direct Role of Chemisorbed (Spectator) Species in the Reaction Mechanism	422	(3)
Role of Acido-Base Properties in Catalytic Oxidation	425	(14)
Basic Concepts on the Acido-Base Characteristics of Metal Oxides	426	(3)
Influence of Acido-Base Characteristics on the Activation of Hydrocarbons	429	(2)
Competitive Surface Reactions and Acido-Base Properties	431	(7)
Role of Acido-Base Properties on the Adsorption/Desorption of Reactants and Products	438	(1)
Reactive Intermediates in Heterogeneous Oxidative Catalysis	439	(17)
Analysis of the Reactive Intermediates by IR Spectroscopy	439	(2)
Chemistry of Oxidation of Methanol	441	(5)
Oxidation of Linear C4 Hydrocarbons	446	(3)
Oxidation of Alkylaromatics	449	(5)
The Case of Ammonia	454	(2)
Presence of Competitive Pathways of Conversion and Factors Governing Their Relative Rates	456	(13)
Propane Ammoxidation on (VO)2P2O7	457	(2)
Toluene Ammoxidation (VO)2P2O7 and V/TiO2 Catalysts	459	(2)
Propane Ammoxidation on V/Sb Oxides	461	(5)
o-Xylene Ammoxidation on V/TiO2 Catalysts	466	(2)
Oxidation of n-Pentane on (VO)2P2O7	468	(1)
Dynamics of Catalytic Oxidation Processes	469	(9)
Relevant Evidence from Surface Science Studies	470	(5)
Dynamics of Oxide Phase Transformation in the Active Form of the Catalysts	475	(2)
Dynamics of Surface Species and Their Effect on Catalyst Surface Properties	477	(1)
Conclusions	478	(19)
References	480	(17)
General Conclusions	497	(4)
Index	501