5.8 Non-oxidative Coupling of Methane . . . . . . . . . . . . . . . . . . . . . . 117
5.8.1 Two-Step Methane Coupling . . . . . . . . . . . . . . . . . . . . . . 117
5.8.2 One-Step Non-oxidative Coupling of Methane . . . . . . . . . 118
5.8.3 Catalysts for the Non-oxidative Coupling of Methane
and the Activation of Methane on the Surface of Metal
Catalysts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 118
5.8.4 High Catalytic Performance of Catalysts with Single
Iron Sites in the Non-OCM Reaction . . . . . . . . . . . . . . . . 119
5.9 Summary of OCM Features . . . . . . . . . . . . . . . . . . . . . . . . . . . . 119
References . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 120
6 Conversion of Methane to Aromatic Hydrocarbons . . . . . . . . . . . . . 127
6.1 Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 127
6.2 Initial Reports of the Methane Dehydroaromatization
Reaction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 128
6.3 Thermodynamics of the Direct Conversion of Methane Under
Non-oxidative Conditions for Hydrocarbon Production . . . . . . . . . 129
6.4 Zeolite-Based Catalysts for the Conversion of Methane
to Aromatic Hydrocarbons . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 130
6.4.1 Catalytic Activities of Mo Species Loaded
on H
+
-Exchanged Zeolites . . . . . . . . . . . . . . . . . . . . . . . . 130
6.4.2 Effect of the Zeolite Pore Structure on the Catalytic
Production of Aromatic Hydrocarbons . . . . . . . . . . . . . . . 133
6.4.3 Effect of the Si/Al Ratios of H
+
-Exchanged Zeolites
on Their Catalytic Performances . . . . . . . . . . . . . . . . . . . . 137
6.4.4 Catalytic Activities of H
+ -Exchanged Zeolites
Modified with Various Metal Species . . . . . . . . . . . . . . . . 140
6.5 Interaction of Mo Species with Brønsted Acid Sites
on H
+
-Exchanged Zeolites . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 141
6.5.1 Methods for the Preparation of Mo-Modified
H-ZSM-5 Catalysts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 141
6.5.2 Formation of Various Mo Species in H
+
-Exchanged
Zeolites . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 142
6.5.3 Chemical Properties of the Mo Species on H-ZSM-5
After Calcination at 773 K . . . . . . . . . . . . . . . . . . . . . . . . 146
6.5.4 Influence of the Si/Al Ratio on the Structure of Mo
Species on H
+
-Exchanged Zeolites After Calcination . . . . . 146
6.6 Mo Species of Mo/H-ZSM-5 Zeolite Catalysts During
the Working Stage . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 148
6.6.1 Changes in the Reaction Products During the Induction
Period . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 149
6.6.2 Changes in the Mo Species During Induction Period . . . . . 149
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5.8.1 Two-Step Methane Coupling . . . . . . . . . . . . . . . . . . . . . . 117
5.8.2 One-Step Non-oxidative Coupling of Methane . . . . . . . . . 118
5.8.3 Catalysts for the Non-oxidative Coupling of Methane
and the Activation of Methane on the Surface of Metal
Catalysts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 118
5.8.4 High Catalytic Performance of Catalysts with Single
Iron Sites in the Non-OCM Reaction . . . . . . . . . . . . . . . . 119
5.9 Summary of OCM Features . . . . . . . . . . . . . . . . . . . . . . . . . . . . 119
References . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 120
6 Conversion of Methane to Aromatic Hydrocarbons . . . . . . . . . . . . . 127
6.1 Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 127
6.2 Initial Reports of the Methane Dehydroaromatization
Reaction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 128
6.3 Thermodynamics of the Direct Conversion of Methane Under
Non-oxidative Conditions for Hydrocarbon Production . . . . . . . . . 129
6.4 Zeolite-Based Catalysts for the Conversion of Methane
to Aromatic Hydrocarbons . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 130
6.4.1 Catalytic Activities of Mo Species Loaded
on H
+
-Exchanged Zeolites . . . . . . . . . . . . . . . . . . . . . . . . 130
6.4.2 Effect of the Zeolite Pore Structure on the Catalytic
Production of Aromatic Hydrocarbons . . . . . . . . . . . . . . . 133
6.4.3 Effect of the Si/Al Ratios of H
+
-Exchanged Zeolites
on Their Catalytic Performances . . . . . . . . . . . . . . . . . . . . 137
6.4.4 Catalytic Activities of H
+ -Exchanged Zeolites
Modified with Various Metal Species . . . . . . . . . . . . . . . . 140
6.5 Interaction of Mo Species with Brønsted Acid Sites
on H
+
-Exchanged Zeolites . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 141
6.5.1 Methods for the Preparation of Mo-Modified
H-ZSM-5 Catalysts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 141
6.5.2 Formation of Various Mo Species in H
+
-Exchanged
Zeolites . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 142
6.5.3 Chemical Properties of the Mo Species on H-ZSM-5
After Calcination at 773 K . . . . . . . . . . . . . . . . . . . . . . . . 146
6.5.4 Influence of the Si/Al Ratio on the Structure of Mo
Species on H
+
-Exchanged Zeolites After Calcination . . . . . 146
6.6 Mo Species of Mo/H-ZSM-5 Zeolite Catalysts During
the Working Stage . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 148
6.6.1 Changes in the Reaction Products During the Induction
Period . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 149
6.6.2 Changes in the Mo Species During Induction Period . . . . . 149
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