Recent Advances in Complete Methane Oxidation using Zeolite‐Supported Metal Nanoparticle Catalysts

Abstract

The high fuel efficiency of natural gas makes it an attractive alternative to coal and oil during the transition towards renewable energy resources. Natural gas engines are needed to ensure a stable power grid that can accommodate fluctuations in renewable energy production. Unfortunately, these engines emit as much as 3-4 % of the methane (CH 4 ) in the natural gas under learn-burn conditions. This methane slip has a high environmental cost since CH 4 is a potent greenhouse gas. Complete catalytic oxidation of CH 4 can potentially control the emission. Unfortunately, the best performing Pd/Al 2 O 3 catalysts suffer from severe deactivation under operating conditions.After decades of little progress, zeolite-supported catalysts have recently attracted increased attention. Here, we review the current status, challenges, and prospects for controlling methane emissions from large engines using zeolite-based catalysts. The determining factors for catalytic activity and stability are the zeolite topology, alumina content, counter-ion, and active metal nanoparticles incorporation. In addition, we highlight the importance of testing under realistic operation conditions. Thus, the review provides a framework for developing a catalyst technology critically needed to fulfill the Paris Climate Agreement.

Zeolite-based catalysts for oxidative upgrading of methane: design and control of active sites

“…Metal nanoparticles encapsulated in zeolites have also been employed for other classes of methane conversion such as combustion and dry reforming. 93,94 Fig. 23…”

Mesoporous Ceria and Ceria‐Praseodymia as High Surface Area Supports for Pd‐based Catalysts with Enhanced Methane Oxidation Activity

“…In this context, the Pd deposition on Ce−Pr supports has been investigated over the past few years, obtaining materials with a higher catalytic activity with respect to Pd/CeO 2 , a better stability of the PdO species in the high temperature range, and an interesting behavior in the presence of water [15,16] . However, these materials were characterized by very low surface area values, while an increase in this parameter can be expected to considerably improve the catalytic performance of these catalysts [17,18] …”

Novel Insights on the Metal–Support Interactions of Pd/ZrO2 Catalysts on CH4 Oxidation

“…Natural gas vehicles, with higher fuel efficiency and lower pollutant emissions, have proven to be cleaner than gasoline and diesel engines . However, the abatement of unburnt CH 4 in the exhaust has brought great challenges to countries and governments worldwide . The most promising technology is to oxidize CH 4 to CO 2 over a catalyst below 500 °C, with the fact that the global warming potential of CH 4 is around 28 times that of CO 2 .…”

“…3 However, the abatement of unburnt CH 4 in the exhaust has brought great challenges to countries and governments worldwide. 4 The most promising technology is to oxidize CH 4 to CO 2 over a catalyst below 500 °C, with the fact that the global warming potential of CH 4 is around 28 times that of CO 2 . 5 To reduce the environmental impact of CH 4 in waste gases, the development of low-temperature catalysts has become an exigent issue.…”