230
catalyst regeneration protocol. Mechanistic studies of MDA reaction also provide
insights to control coke content by identifying active sites. With this purpose, here
we intend to deliver insights on MDA reaction catalysed by zeolite-supported
molybdenum catalyst and investigations on catalyst stability controlling coke deposition by providing an overview of combined theoretical and experimental studies.
In this book chapter, different ways to control the catalytic activity and stability
have been discussed based on catalytic parameters and reactor configurations.
Keywords Natural gas · Methane dehydroaromatization · Molybdenum carbide ·
Mo/zeolite · Carburization
1 Introduction
Large reserves of natural gas, shale gas and methane hydrates worldwide are attracting attention of industrial and academic community as a potential source of clean
energy and feedstock for value-added chemicals. However, most of these reserves
of methane are located in remote areas which impart gas transportation challenges
over long distances to populated areas and hence economically not feasible. This
emphasizes the development of technologies for onsite methane (major source of
natural/shale gas) conversion into transportable liquid and other high-value chemicals such as olefins, paraffins, aromatics and hydrogen. Methane, which is the major
content of natural gas, is a thermodynamically stable molecule emerging challenges
to the chemical community for its activation and direct conversion into useful chemicals. Schematic pathways, currently known, for methane utilization producing
value-added chemicals are depicted in Fig. 1. From decades, routes for methane
upgradation are explored which involves indirect pathway where methane is first
reformed into a mixture of CO and H 2 (synthesis gas), using steam or partial oxidative reforming [1, 2]. From syn-gas (CO + H 2 ), methanol, dimethyl ether (DME)
and other high-value chemicals such as paraffins, olefins, gasoline and diesel can be
produced using Fischer Tropsch (FT) process [3, 4]. Methane utilization via syn-gas
route has been successfully commercialized and different plants are currently in
operation [5]. However, reactions involving syn-gas route require severe high temperature and high pressure conditions and hence the production of syn-gas and its
compression typically accounts high capital costing and is energy-intensive for
operating the plants [5]. Investigating other direct alternative routes to reduce economy and energy consumption relative to indirect syn-gas processing, it is expected
that direct methane conversion route producing value-added chemicals also require
high temperatures due to high chemical inertness of methane molecule. Direct
methane conversion into chemicals without going through the intermediate step of
syn-gas production involves oxidative or non-oxidative treatment. In direct routes of
S. Mishra et al.
catalyst regeneration protocol. Mechanistic studies of MDA reaction also provide
insights to control coke content by identifying active sites. With this purpose, here
we intend to deliver insights on MDA reaction catalysed by zeolite-supported
molybdenum catalyst and investigations on catalyst stability controlling coke deposition by providing an overview of combined theoretical and experimental studies.
In this book chapter, different ways to control the catalytic activity and stability
have been discussed based on catalytic parameters and reactor configurations.
Keywords Natural gas · Methane dehydroaromatization · Molybdenum carbide ·
Mo/zeolite · Carburization
1 Introduction
Large reserves of natural gas, shale gas and methane hydrates worldwide are attracting attention of industrial and academic community as a potential source of clean
energy and feedstock for value-added chemicals. However, most of these reserves
of methane are located in remote areas which impart gas transportation challenges
over long distances to populated areas and hence economically not feasible. This
emphasizes the development of technologies for onsite methane (major source of
natural/shale gas) conversion into transportable liquid and other high-value chemicals such as olefins, paraffins, aromatics and hydrogen. Methane, which is the major
content of natural gas, is a thermodynamically stable molecule emerging challenges
to the chemical community for its activation and direct conversion into useful chemicals. Schematic pathways, currently known, for methane utilization producing
value-added chemicals are depicted in Fig. 1. From decades, routes for methane
upgradation are explored which involves indirect pathway where methane is first
reformed into a mixture of CO and H 2 (synthesis gas), using steam or partial oxidative reforming [1, 2]. From syn-gas (CO + H 2 ), methanol, dimethyl ether (DME)
and other high-value chemicals such as paraffins, olefins, gasoline and diesel can be
produced using Fischer Tropsch (FT) process [3, 4]. Methane utilization via syn-gas
route has been successfully commercialized and different plants are currently in
operation [5]. However, reactions involving syn-gas route require severe high temperature and high pressure conditions and hence the production of syn-gas and its
compression typically accounts high capital costing and is energy-intensive for
operating the plants [5]. Investigating other direct alternative routes to reduce economy and energy consumption relative to indirect syn-gas processing, it is expected
that direct methane conversion route producing value-added chemicals also require
high temperatures due to high chemical inertness of methane molecule. Direct
methane conversion into chemicals without going through the intermediate step of
syn-gas production involves oxidative or non-oxidative treatment. In direct routes of
S. Mishra et al.