Chapter 1 Strong Solid Bases for Organic Reactions .............. 1
By Yoshio Ono and Toshihide Baba
1 Introduction ................................................. 1
2 Role of Solid Base and Basic Sites as a Catalyst ............. 2
2.1 Abstraction of Protons .................................. 2
2.2 Activation of Reactants without Proton Abstraction ...... 2
2.3 Cooperative Action of Acidic and Basic Sites ............ 2
3 Base Strength of Basic Sites ................................. 3
3.1 H_ Acidity Function ..................................... 3
3.2 Indicator Method ........................................ 3
3.3 Other Methods for Determining Basic Strength ............ 4
4 Base Strength and Catalytic Reactions ........................ 5
5 Solid Base Materials ......................................... 8
5.1 Alkaline Earth Oxides ................................... 8
5.2 Alkali Metals Supported on Metal Oxides ................. 9
5.3 Alkali Metals on Al2O3 Treated with Alkali Metal
Hydroxides ............................................. 10
5.4 KNH2/Al2O3 ............................................. 10
5.5 Alkali Metal Compound Supported on Alumina ............. 14
5.5.1 KNO3/A2O3, K2CO3/Al2O3, К2СО3/Аl2O3 .............. 14
5.5.2 LiOH/Al2O3, NaOH/Al2O3, KOH/Al2O3, RbOH/AL2O3,
CsOH/Al2O3 ...................................... 14
5.6 Zeolites ............................................... 14
5.7 Modified Zeolites ...................................... 15
5.8 Eu,Yb/Al2O3 ............................................ 16
5.9 KF/Al2O3 ............................................... 16
5.10 Mixed Oxides ........................................... 18
6 Reactions Catalysed by Solid Bases .......................... 20
6.1 Isomerizations ......................................... 20
6.1.1 Isomerization of Alkenes ........................ 20
6.1.2 Isomerization of Alkenyl Amines ................. 20
6.1.3 Isomerization of Allyl Ethers ................... 21
6.1.4 Isomerization of Alk-1-ynes ..................... 21
6.2 Nucleophilic Addition Reactions of Phenylacetylene ..... 21
6.2.1 Dimerization of Phenylacetylene ................. 21
6.2.2 Reactions of Alk-1-yne with Ketone or
Aldehyde ........................................ 22
6.3 Aldol-type Condensations ............................... 25
6.3.1 Aldol Condensations ............................. 25
6.3.2 Claisen-Schmidt Reactions ....................... 25
6.3.3 Knoevenagel Condensations ....................... 27
6.3.4 Michael Additions ............................... 28
6.3.5 Dehydrocondensation with Methanol ............... 28
6.4 Nucleophilic Substitution at Silicon - Si-C Bond
Formation .............................................. 28
6.4.1 Metathesis of Trimethylsilylacetylene ........... 29
6.4.2 Cross-metathesis of Alkynes ..................... 30
6.4.3 Reaction of Alk-1-yne with Silane ............... 30
6.4.4 Reaction of Alk-1-ene with Diethylsilane ........ 31
6.4.5 Reaction of Toluene with Diethylsilane .......... 31
6.5 Miscellaneous Reactions ................................ 32
6.5.1 Tishchenko Reaction ............................. 32
6.5.2 Reactions of Silanes with Ketones or
Aldehydes ....................................... 33
6.5.3 Reaction of Aniline with
Trimethylsilylacetylene ......................... 33
6.5.4 Ring Opening of Epoxides with Me3SiCN ........... 34
6.5.5 Hydrocyanation .................................. 34
6.5.6 Alkylations ..................................... 34
6.5.7 Formation and Ring Transformations of
Heterocycles .................................... 35
7 Concluding Remarks - Unsolved Problems ...................... 35
References .................................................. 36
Chapter 2 Catalysis by Solid Bases ............................. 40
By Eric J. Doskocil, Shailendra Bordawekar and Robert
J. Davis
1 Introduction ................................................ 40
2 Types of Basic Catalysts .................................... 41
2.1 Supported Alkali Metal Oxides .......................... 41
2.2 Hydrotalcites .......................................... 41
2.3 Zeolites and Mesoporous Oxides ......................... 42
2.4 Alkali Metals Supported on Nanoporous Carbon ........... 44
2.5 Basic Phosphate Oxynitride Catalysts ................... 45
3 Characterization of Solid Base Catalysts ..................... 45
3.1 Theoretical Ranking of Solid Basicity .................. 46
3.1.1 Sanderson Intermediate Electronegativity ........ 46
3.1.2 Molecular Orbital Calculations .................. 46
3.2 Experimental Ranking of Solid Basicity ................. 47
3.2.1 Infrared Spectroscopy of Adsorbed Probe
Molecules ....................................... 47
3.2.2 Visible Absorption Spectroscopy of Adsorbed
Iodine .......................................... 50
3.2.3 Microcalorimetry of Adsorbed Probe Molecules .... 52
3.2.4 Temperature Programmed Desorption (TPD)
-Butadiene ......................................
of Probe Molecules .......................................... 54
3.2.5 X-Ray Absorption Spectroscopy ................... 54
3.2.6 X-Ray Photoelectron Spectroscopy ................ 56
4 Probe Reactions over Solid Base Catalysts ................... 57
4.1 Double-bond Isomerization .............................. 58
4.2 Alcohol Dehydrogenation ................................ 59
4.3 Hydrogenation Reactions ................................ 60
4.4 Condensation Reactions ................................. 61
4.4.1 Aldol Condensation .............................. 61
4.4.2 Knoevenagel Condensation ........................ 62
4.5 Alkylation Reactions ................................... 63
4.6 Side-chain Alkenylation of o-Xylene with
1,3-Butadiene .......................................... 64
4.7 Miscellaneous Reactions ................................ 65
5 Conclusions ................................................. 67
Acknowledgements ............................................ 67
References .................................................. 67
Chapter 3 Solid Sorbents for Catalytic NOx Removal ............. 73
By Masato Machida
1 Introduction ................................................ 73
2 Materials for NOx Sorption .................................. 74
2.1 Carbonaceous Solids .................................... 74
2.2 Zeolites ............................................... 75
2.3 Alumina ................................................ 76
2.4 Alkaline Solids ........................................ 77
2.5 Transition Metal Oxides containing Alkaline Earths ..... 78
2.6 NOx Intercalation Compounds ............................ 82
2.7 Non-alkaline Solid Oxides .............................. 83
2.8 Heteropoly Compounds ................................... 87
3 Regeneration of NOx Sorbent ................................ 88
3.1 Pressure Swing Process ................................. 89
3.2 Thermal (Temperature) Swing Process .................... 90
3.3 Reduction-Oxidation Cycles ............................. 90
4 Practical Applications of NOx Sorption ...................... 90
4.1 Flue Gas Treatment for Stationary Sources .............. 90
4.2 Automobile NOx Storage Catalysts ....................... 92
5 Conclusion .................................................. 93
References .................................................. 93
Chapter 4 Partial Oxidation of Light Alkanes in Short Contact
Time Microreactors ............................................. 98
By P. Aghalayam, Y.K. Park and D.G. Vlachos
1 Introduction ................................................ 98
2 CH4 Partial Oxidation on Platinum and Rhodium Catalysts ..... 99
2.1 Unsupported Catalysts ................................. 101
2.2 Foam and Extruded Monoliths ........................... 103
2.3 Fluidized Beds ........................................ 103
2.4 The Effect of the Support and Pore Diameter ........... 104
3 Influence of Operating Conditions .......................... 104
3.1 Temperature ........................................... 104
3.2 Flow Velocity and Contact Time ........................ 104
3.3 Pressure .............................................. 107
3.4 Dilution .............................................. 108
3.5 Inlet Fuel Composition ................................ 108
3.6 Influence of Different Surface Coverages .............. 109
4 Analysis of the Effect of Operating Conditions ............. 110
4.1 Model ................................................. 110
4.2 Flow Velocity ......................................... 112
4.3 Temperature ........................................... 113
5 Bifurcation of Methane-Oxygen Mixtures Near Catalysts ...... 114
5.1 'Influence of Fuel Composition ........................ 114
5.2 Influence of Pressure and Flow Velocity ............... 118
5.3 The Inhibiting Role of the Catalyst in Gas-phase
Ignition .............................................. 118
5.4 Importance of Gas-phase Reactions ..................... 119
6 Direct versus Indirect Path to Syngas Formation ............ 121
7 A Quantitative Reaction Mechanism for Oxidation of
Methane .................................................... 125
7.1 Currently Proposed Mechanisms ......................... 125
7.1.1 Selectivity Mechanisms ......................... 125
7.1.2 Catalytic Ingition Mechanisms .................. 126
7.1.3 Other Proposed Reaction Pathways ............... 126
7.2 Limitations of the Existing Detailed Surface
Reaction Mechanisms ................................... 126
7.2.1 Adsorption of CH4 .............................. 127
7.2.2 The Role of Adsorbed Oxygen .................... 128
7.2.3 Adsorbate-Adsorbate Interactions ............... 129
7.2.4 Other Limitations .............................. 129
8 Partial Oxidation of Ethane and Higher Alkanes ............. 130
8.1 Production of Olefins from Alkanes using Pt and Rh .... 131
8.2 The Mechanism of Alkane Dehydrogenation ............... 131
9 Conclusions and Outlook .................................... 133
Acknowledgement ............................................ 134
References ................................................. 134
Chapter 5 Indirect Liquefaction - Where Do We Stand? ......... 138
By Yongqing Zhang and Burtron H. Davis
1 Introduction ............................................... 138
2 Today's Commercial Operations .............................. 139
2.1 South Africa .......................................... 140
2.2 Sasol ................................................. 140
2.3 Mossgas ............................................... 145
2.4 Shell ................................................. 145
3 Large Pilot/Demonstration Plant Operations ................. 148
3.1 Rheinpresussen-Koppers ................................ 148
3.2 British Fuel Research Station ......................... 153
3.3 US Bureau of Mines .................................... 153
3.4 Stanolind/Carthage Hydrocol ........................... 155
4 Standard Oil Co. (New Jersey) - Exxon ...................... 156
5 Pilot Scale Operations ..................................... 161
5.1 Syntroleum ............................................ 161
5.2 Gulf Oil .............................................. 170
5.3 Rentech ............................................... 171
5.4 Chinese Studies ....................................... 172
5.5 Mobil Oil ............................................. 172
6 Process and Economic Evaluations ........................... 174
7 Potential Commercial Operations ............................ 175
8 Summary of Current Status .................................. 180
Acknowledgement ............................................ 182
References ................................................. 182
Chapter 6 Partial Oxidation of Methane Over Silicomolybdic
Acid Catalysts ................................................ I85
By Akifumi Ueno
1 Introduction ............................................... 185
2 Partial Oxidation of Methane on MoO3/SiO3 and Alkali
Metal-doped MoOySK ......................................... 186
3 Active Sites on MoO3/SiO2 and Reaction Mechanism of
Selective Oxidation of Methane ............................. 192
4 Characterization of Surface Species Generated on
MoO3/SiO2 by Heat Treatments ............................... 197
5 Catalytic Activity of SMA Generated On or Impregnated
on SiO2 .................................................... 204
6 Other Topics Concerning Heteropoly Acid Catalysts or
Partial Oxidation of Methane ............................... 208
7 Summary of the Selective Oxidation of Methane on
MoO3/SiO2 Catalysts ........................................ 211
References ................................................. 212
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