Russian Journal of Applied Chemistry, 2009, Vol. 82, No. 2, pp. 307−311.
Pleiades Publishing, Ltd., 2009.
Original Russian Text
S.S. Sigaeva, P.G. Tsyrul’nikov, D.A. Shlyapin, T.S. Dorofeeva, N.N. Voitenko, V.I. Vershinin, N.A. Davletkil’deev, G.B. Kuznetsov,
S.L. Kanashenko, 2009, published in Zhurnal Prikladnoi Khimii, 2009, Vol. 82, No. 2, pp. 313−316.
AND INDUSTRIAL ORGANIC CHEMISTRY
Catalysts of Methane Pyrolysis: Pretreatment and Study
of Fechral Support
S. S. Sigaeva, P. G. Tsyrul’nikov, D. A. Shlyapin, T. S. Dorofeeva, N. N. Voitenko,
V. I. Vershinin, N. A. Davletkil’deev, G. B. Kuznetsov, and S. L. Kanashenko
Institute of Hydrocarbon Processing Problems, Siberian Branch, Russian Academy of Sciences, Omsk, Russia
Dostoevsky State University, Omsk, Russia
Hitachi High-Technologies, Moscow, Russia
Received April 9, 2008
Abstract—The pretreatment of Fechral support for preparing a methane pyrolysis catalyst was studied. The Fechral
support after high-temperature (1000°C) treatment in air was examined by atomic force microscopy, scanning
electron microscopy with chemical analysis, and X-ray phase analysis of the surface layer. The morphological,
chemical, and phase changes on the support surface were studied. A mechanism of formation of the dispersed
phase on the Fechral surface was suggested.
Efficient utilization of hydrocarbon resources and
development of new resource-saving and environmentally
clean technologies acquire growing importance today.
From the environmental viewpoint, methane is the
cleanest natural energy source. Methane is used today in
industry for production of energy and also of synthesis
gas, hydrogen, halogen derivatives, and HCN .
Markedly growing interest in the hydrogen fuel and its
use in means of transportation [2–4] makes problems of
hydrogen production and storage urgent. It is suggested
to use hydrogen for direct combustion in internal
combustion engines, as additives to organic fuel, but
mainly in fuel cells. Electric cars with fuel cells can
be considerably more efﬁ cient than cars with internal
combustion engines. Furthermore, the environmental
advantages or fuel cells are obvious: only water vapor
is formed in combustion of hydrogen.
Pure hydrogen can be prepared, in particular,
by endothermic decomposition of methane (main
component of natural gas) on an appropriate catalysts,
e.g., on palladium alloys . The most active in
this process are catalysts based on transition metals,
primarily Ni, Co, and Fe applied onto Al
-based supports [6–8]. The generally accepted
mechanism of methane decomposition, carbide cycle
mechanism [7–12], suggests initial decomposition of
methane on less closely packed faces (100, 010) of
metal crystals, dissolution of carbon in the crystal up
to saturation, and formation of graphite layers on the
close-packed (111) face. The propagating carbon thread
can detach the crystal from the support and transfer it
into the intergrain space. In the course of the subsequent
oxidative regeneration of the catalyst, dispersed particles
of the metal (or oxide formed) are removed with the gas
ﬂ ow. In the process, the catalyst is destroyed.
Presumably, the use of heat-resistant all-metal
supports with a strong surface oxide layer containing
active elements would allow preparation of new catalysts
of methane decomposition, which not only would be
interesting for basic science but also would withstand
repeated regenerations. In this study we took as support
Fechral, an alloy used, in particular, in production of
metallic blocks for automobile exhaust afterburning.
The surface of the initial Fechral alloy has almost no
adsorption centers. This complicates application of nickel
and other iron-group metals onto the support surface.
The use of Fechral as support requires increasing its
speciﬁ c surface area, forming appropriate morphology,
and changing the composition of the surface layer, which
can be attained by pretreatment.
The goal of this study was to develop a procedure and
ﬁ nd conditions of Fechral treatment for developing its