Methane decomposition catalysts for COx-free hydrogen production

Abstract

Catalytic decomposition of methane into CO x -free hydrogen and carbon nanofibers has recently attracted much attention. The development of high-performance catalysts is essential for production of CO x -free hydrogen from methane. In this review we summarize the catalytic systems used for methane decomposition and compare catalysts with different active components and supports. According to the literature and our recent research results, Ni is the most active metal for methane decomposition and its catalytic performance can be enhanced by doping with metals such as Pd and Cu, especially for high reaction temperatures. The nature and origin of the surface are the main factors that influence the performance of carbon catalysts.

Activation and Decomposition of Methane over Cobalt‐, Copper‐, and Iron‐Based Heterogeneous Catalysts for COx‐Free Hydrogen and Multiwalled Carbon Nanotube Production

“…This finding is of prime importance economically because bimetallic precursors are much more expensive than their monometallic analogues. It has been proven that transition metals of Period 4, namely, cobalt, iron, and nickel, display the highest activities, but grant only a short catalyst duration . The same trend was observed for Co/Al 2 O 3 and Fe/Al 2 O 3 catalysts herein.…”

“…The accessibility of the metal surface for hydrocarbon molecules has been regarded as a highly important factor that determines catalytic decomposition activity . In general, it has been reported that a direct correlation may be observed between the electronegativity of the metal loaded on the catalyst and the catalytic activity for CDM reactions . The susceptibility of the interaction and adsorption of CH 4 molecules by metal species increases with increasing electronegativity of metals .…”

“…All bimetallic Fe−M catalysts reduced the reaction temperature by 400–500 °C, relative to that of noncatalytic thermal decomposition (at comparable conversions), and exhibited a higher activity than that of monometallic Fe/Al 2 O 3 catalyst. With respect to catalytic performance, Fe−Pd was the most effective catalyst, achieving a H 2 yield of 80 % at 700 °C, compared with 75 and 65 % when using Fe−Mo and Fe−Ni, respectively . Shen and co‐workers examined bimetallic Fe−Ni nanoparticles, supported on Mg(Al)O, for the CDM in the temperature range of 600–700 °C .…”

Methane Activation

“…[15][16][17][18][19][20] Additionally, a review article of Choudhary et al gives more details on the nonoxidative activation of CH 4 . [15][16][17][18][19][20] Additionally, a review article of Choudhary et al gives more details on the nonoxidative activation of CH 4 .…”

“…152, 153 Diefenbach et al combined experiments in the gas phase on reactions of Pt þ with NH 3 , CH 4 , and CH 3 NH 2 in a Fourier transform ion cyclotron resonance mass spectrometer with theoretical studies. 156 In the Andrussow process, originally developed by BASF, the feed gas mixture contains additional O 2 to burn the H 2 , resulting in an exothermic reaction, as shown in eqn [18]. CH 4 is thought to be dehydrogenated over Pt to a carbene species, which then react with NH 3 from the gas phase to an intermediate species with a C-N bond.…”