Pillared Clays and Related Catalysts (eBook)

Foreword 4
Preface 6
Contents 9
Contributors 11
1 Microwave Effect on Clay Pillaring 15
1.1 Introduction 15
1.2 Experimental 17
1.3 Determinant Conditions 17
1.3.1 Irradiation Time 17
1.3.1.1 Alumina-Pillared Montmorillonite 17
1.3.1.2 Zirconia-Pillared Montmorillonite 19
1.3.1.3 Titania-Pillared Montmorillonite 20
1.3.1.4 Multimetallic-Pillared Montmorillonite 21
1.3.1.5 Remarks 22
1.3.2 Clay to Water Ratio 22
1.3.2.1 Alumina-Pillared Montmorillonite 22
1.3.2.2 Iron oxide-Pillared Montmorillonite 22
1.3.2.3 Remarks 23
1.3.3 Metal to Clay Ratio 23
1.3.3.1 Titanium-Pillared Clays 23
1.3.3.2 Zirconium-Pillared Montmorillonite 23
1.3.3.3 Remarks 24
1.3.4 Ultrasound Versus Microwave Irradiation 24
1.3.4.1 Remarks 26
1.4 Other Clays 27
1.4.1 Clay Synthesis 27
1.4.2 Aluminum-Intercalated Samples 27
1.4.3 Titania-Pillared Clays 27
1.4.4 Chromia and Tin Oxide-Pillared Montmorillonites and Laponites 28
1.4.5 Saponite Pillared with Fe-Organometallic by Microwave and Ultrasound Irradiation 29
1.4.6 Pillared Anionic Clays 29
1.4.6.1 Polyvanadate-Intercalated Hydrotalcites 29
1.4.6.2 PO430 and P2O740-Intercalated Hydrotalcites 30
1.4.6.3 PET-Hydrotalcite Nanocomposites 30
1.4.6.4 Remarks 30
1.5 Conclusion 31
References 31
2 Pillared Interlayered Clays as Adsorbents of Gases and Vapors 36
2.1 Introduction 36
2.2 Adsorption of Volatile Organic Compounds (VOCs) 37
2.2.1 As Probe Molecules 37
2.2.2 For Separation/Purification 39
2.3 Adsorption of Water 41
2.4 Adsorption of Natural and Biogas Components 43
2.5 Conclusion 53
References 53
3 Characterization and Catalytic Performance of Montmorillonites with Mixed Aluminium/Lanthanide Pillars 56
3.1 Introduction 56
3.2 Experimental Section 57
3.2.1 Starting Material 57
3.2.2 Synthesis 57
3.2.2.1 Preparation of the Pillaring Agents 57
3.2.2.2 Pillaring Process 58
3.3 Results and Discussion 58
3.3.1 X-ray Diffraction (CuK radiation) 59
3.3.2 MAS NMR Spectra 59
3.3.3 Textural Analysis 62
3.3.4 Acidity of Samples 67
3.3.5 Catalytic Activity 69
3.4 Conclusions 76
References 76
4 Synthetic Hectorite: Preparation, Pillaring and Applications in Catalysis 79
4.1 Introduction 79
4.2 Properties and Structure of Hectorite 81
4.3 Synthesis of Hectorite-Like Solids 83
4.3.1 A Brief History of Synthetic Hectorite 83
4.3.2 Synthesis Variables and Structure Characteristics 89
4.4 Pillaring and Further Modification 94
4.5 Catalysis 98
4.6 Summary and Prospects 102
References 103
5 Transition Metal Oxide-Pillared Clay Catalyst: Synthesis to Application 110
5.1 Introduction 110
5.2 Pillaring Process 111
5.2.1 Polynuclear Metal Oxo--hydroxo Cations 112
5.2.2 Cationic Metal Complex 112
5.2.3 Metal Cluster Complex 112
5.2.4 Positively Charged Colloidal Particles 113
5.3 Synthesis of Transition Metal Oxide-Pillared Clays 113
5.3.1 Titanium Oxide-Pillared Clays 116
5.3.2 Iron Oxide-Pillared Clays 117
5.3.3 Chromium Oxide-Pillared Clays 119
5.3.4 Manganese Oxide-Pillared Clay 121
5.3.5 Mixed Transition Metal Oxide-Pillared Clay 121
5.4 Acidity of Pillared Clay 123
5.4.1 Acid Activation of Clay Before Pillaring 124
5.4.2 Anion-Supported Pillared Clay 124
5.5 Catalytic Reaction 126
5.5.1 Acidic Reaction 126
5.5.2 Redox Reaction 127
5.5.3 Selective Catalytic Reduction (SCR) of NO x 128
5.5.4 Photocatalytic Reaction 130
5.6 Conclusions 131
References 132
6 Use of Pillared Clay-Based Catalysts for Wastewater Treatment Through Fenton-Like Processes 140
6.1 Introduction 140
6.1.1 Water Treatment with Advanced Oxidation Processes 140
6.1.2 The Use of Pillared Clays in Heterogeneous Fenton-Based Processes 142
6.1.3 Pollutants Degraded or Wastewaters Treated with Pillared Clay-Based Catalysts 144
6.2 Fenton and Fenton-Like Process 145
6.2.1 Introduction 145
6.2.2 Effect of the Main Operating Conditions 147
6.2.2.1 Effect of the Initial pH 147
6.2.2.2 Effect of the Temperature 151
6.2.2.3 Effect of the Initial H 2 O 2 Concentration 152
6.2.2.4 Effect of the Catalyst Load 153
6.2.2.5 Effect of the Initial Parent Compound Concentration 157
6.2.2.6 Heterogeneous Versus Homogenous Process 157
6.2.3 Effect of the Type of Catalyst/Salt Precursor 159
6.2.4 Some Technological Issues 161
6.2.4.1 Catalyst Stability 161
6.2.4.2 Use of Continuous Flow Reactors 164
6.2.5 Mechanistic Studies 165
6.3 Modeling 165
6.3.1 Phenomenological Models 166
6.3.1.1 Langmuir--Hinshelwood Rate Equations 166
6.3.1.2 Apparent First-Order Rate Equations 170
6.3.2 Non-Phenomenological Models 170
6.4 Conclusions 172
References 173
7 Catalytic Wastewater Treatment Using Pillared Clays 177
7.1 Introduction 177
7.1.1 Issues in Using Solid Catalysts in Wastewater Treatment 179
7.1.2 PILCs and Catalytic AOP Methods 180
7.2 Wet Air Catalytic Oxidation ( WACO ) 182
7.2.1 PILC-Based Catalysts for Wet Oxidation 183
7.3 Wet Hydrogen Peroxide Catalytic Oxidation (WHPCO) 186
7.3.1 Heterogeneous Versus Homogeneous Reactions 188
7.3.2 Mechanism of Organic Transformation 192
7.3.3 A Survey of Literature Data on the Use of PILC-Based Materials 193
7.4 Photocatalytic Behavior of Ti-PILC and Fe-PILC 197
7.4.1 Ti-PILC 197
7.4.2 Fe-PILC for Photo-Fenton 201
7.5 Conclusions 202
References 203
8 FeAl-Pillared Clays: Catalysts for Wet Peroxide Oxidation of Phenol 211
8.1 Introduction 211
8.2 Experimental 212
8.2.1 Catalysts 212
8.2.2 Catalytic Phenol Oxidation 213
8.2.2.1 Reaction 213
8.2.2.2 Batch Reactor 214
8.2.2.3 Dynamic Fixed-Bed Reactor 214
8.2.2.4 Mössbauer Spectroscopy 215
8.2.2.5 ESR Spectroscopy 215
8.3 Results and Discussion 216
8.3.1 Phenol Oxidation 216
8.3.1.1 Batch Reactor 216
8.3.2 Catalyst Characterizations 226
8.3.2.1 Mössbauer 226
8.3.2.2 ESR 227
8.4 Conclusion 231
References 232
9 Pillared Clay-Supported Noble Metal and Metal Oxide Catalysts for Complete Oxidation of VOCs 235
9.1 Introduction 235
9.2 Pillared Clay-Supported Noble Metal Catalysts for Complete Oxidation of VOCs 236
9.3 Pillared Clay-Supported Metal Oxide Catalysts for Complete Oxidation of VOCs 249
9.4 Pillared Clays as Catalysts for Complete Oxidation of VOCs 259
9.5 Conclusions 261
References 261
10 Clay Materials for Selective Catalytic Reduction of NOx 265
10.1 Introduction 265
10.1.1 NOx Definition 265
10.1.2 NOx Origin 266
10.1.3 NOx Environmental Effects 267
10.1.4 Legislative Aspects 269
10.1.5 NOx Reduction Ways 269
10.1.6 NOx Removal by Catalytic Technologies 273
10.1.6.1 Selective Catalytic Reduction with Ammonia 273
10.1.6.2 Selective Catalytic Reduction with Hydrocarbons 275
10.1.6.3 Catalytic Reduction with CO 279
10.1.6.4 Catalytic Decomposition 280
10.2 Pillared Clays as DeNO x Catalysts 281
10.2.1 NOx Reduction with Ammonia 281
10.2.2 NOx Reduction with Hydrocarbons 289
10.2.3 NOx Catalytic Reduction with CO and NOx Catalytic Decomposition 293
10.3 HDL as DeNOx Catalysts 294
10.4 Porous clay Heterostructures (PCH) as DeNO x Catalysts 297
10.5 Concluding Remarks 299
References 300
11 Pillared Clay Catalysts in Green Oxidation Reactions 311
11.1 Introduction 311
11.2 Alkene Oxidation 312
11.2.1 Epoxidation 312
11.2.2 Oxidative Ketonization 315
11.2.3 Allylic Oxidation 316
11.3 Alkylaromatic Oxidation 317
11.3.1 Aromatic Ring Oxidation 317
11.4 Oxidation of Compounds Containing Oxygen 317
11.4.1 Alcohol Oxidation 317
11.4.2 Phenol Oxidation 318
11.4.3 Allylic Alcohol Epoxidation 320
11.5 Heteroatom Oxidation 321
11.5.1 Amine Oxidation 321
11.5.2 Sulfoxidation 322
11.6 Conclusions 322
References 323
12 Heterogeneous Catalysis by Polyoxometalate-Intercalated Layered Double Hydroxides 329
12.1 Introduction 329
12.2 Vanadium-Containing LDHs 337
12.3 Chromium-Containing LDHs 348
12.4 Molybdenum-Containing LDHs 354
12.5 Tungsten-Containing LDHs 367
12.6 Miscellaneous Systems 388
12.6.1 Boron-Containing LDHs 388
12.6.2 Manganese-Containing LDHs 389
12.6.3 Niobium-Containing LDHs 391
12.6.4 Osmium-Containing LDHs 392
12.7 Conclusions 395
References 395
13 Basicity, Catalytic and Adsorptive Properties of Hydrotalcites 408
13.1 Introduction 408
13.2 Activation of HDT 409
13.3 Recent Applications of HDT as Basic Catalyst 410
13.3.1 Isomerisation of Olefins 410
13.3.2 Aldolisation 411
13.3.3 Meerwein--Ponndorff--Verley Reductions of Carbonyls 413
13.3.4 Oxidations 414
13.4 Bifunctional Catalysis 416
13.5 Support Effects on Palladium 417
13.5.1 Electronic Effects 417
13.5.2 Catalytic Properties for Hydrogenations 418
13.5.3 Dechlorination of Trichlorobenzene 418
13.5.4 Catalysis of C--C Coupling Reactions 418
13.5.5 Merox Process 419
13.6 Solid Bases as Adsorbents and Anionic Exchangers 419
13.6.1 Trapping of Organic Compounds and Anions 419
13.6.2 SOx Additives for FCC 421
13.6.3 NOx Traps 422
13.7 Hydrotalcites as Reservoirs for Drugs 422
13.8 Conclusions 424
References 425
14 Mesoporous Phosphate Heterostructures: Synthesis and Application on Adsorption and Catalysis 432
14.1 Introduction 433
14.2 Synthesis of SiPPH 434
14.3 Doping the Silica Galleries 437
14.4 Functionalisation of Silica Galleries 439
14.5 PPH as Support of Other Chemical Species 442
14.6 Applications in Catalysis and Adsorption of SiPPH 445
References 452
15 Recent Advances in the Preparation and Application of Mesoporous Aluminophosphate-Based Materials 456
15.1 Introduction 456
15.2 Synthesis 457
15.3 Surfactant Removal 458
15.4 Block Copolymers as Surfactants 459
15.5 Aluminophosphate Modification 462
15.6 Applications of Mesoporous Aluminophosphates and Metal Aluminophosphates 465
15.7 Conclusions 468
References 469
16 Heterogeneous Complex Catalysts Having Ionically Macrocyclic Complex Bonded to Montmorillonite Clay for Industrial Reactions 473
16.1 Introduction 473
16.1.1 Montmorillonite as Catalyst 473
16.1.2 Complexes 474
16.1.3 Scope of the Present Work 490
16.2 Experimental 494
16.2.1 Preparation of the Macrocyclic Complex 494
16.2.1.1 Preparation of 2,6-Diformyl-4-methylphenol (Dialdehyde) 494
16.2.1.2 Synthesis of Homonuclear CuCuL-1,2(CH 3 COO) [L-1 =(CH 3 C 6 H 2 (CH) 2 ON 2 C 6 H 4 ) 2 ] Macrocyclic Complex 496
16.2.1.3 Synthesis of Heterobinuclear FeCuL-2 (NO 3 ) 2 04H 2 O Macrocyclic Complex, L-2 = (CH 3 C 6 H 2 (CH) 2 O(CH 2 ) 3 N 2 ) 2 497
16.2.2 Synthesis of the Heterogeneous Complex Catalyst 499
16.3 Characterization of the Complexes and Their Catalysts 500
16.3.1 FTIR Analysis of Complex 500
16.3.2 C--H--N Analysis of the Complex 500
16.3.3 Scanning Electron Microscopy of the Complex and the Catalyst 503
16.3.4 Single--Crystal X-Ray Analysis of the Complex 503
16.3.5 Thermogravimetric Analysis (TGA) of the Complex and the Catalyst 505
16.3.6 Small-Angle X-Ray Diffraction Analysis of the Catalyst 505
16.4 Catalytic Oxidation of Cyclohexane Using Oxygen 506
16.4.1 Introduction 506
16.4.2 Reaction Procedure 509
16.4.3 Test for the Absence of Cyclohexyl Hydroperoxide in the Reaction Mass 510
16.4.4 Metal Leaching Test 511
16.4.5 Oxidation of Cyclohexane in the Presence of FeCuL-2/Montmorillonite and CuCuL-1/Montmorillonite Catalysts 511
16.4.6 Reaction Mechanism 512
16.4.7 Optimal Data Fitting 516
16.5 Conclusions 519
References 519
Index 525