ISSN 1070-4272, Russian Journal of Applied Chemistry, 2013, Vol. 86, No. 3, pp. 458−461. © Pleiades Publishing, Ltd., 2013.
Original Russian Text © A.V. Kulichkov, K.V. Semikin, N.V. Kuzichkin, N.V. Lisitsyn, 2013, published in Zhurnal Prikladnoi Khimii, 2013, Vol. 86, No. 3,
pp. 490−493.
BRIEF
COMMUNICATIONS
The Study of Supported Manganese Catalysts
in the Course of the Oxidative Coupling of Methane
A. V. Kulichkov, K. V. Semikin, N. V. Kuzichkin, and N. V. Lisitsyn
St. Petersburg State Institute of Technology (Technical University)., St. Petersburg, Russia
e-mail: kul@ntik.ru
Received February 22, 2013
Abstract—The effect of the process parameters on the yield of the main products, ethane and ethylene, was studied
for the methane oxidative dimerization over manganese catalysts deposited on solid carrying agents. The effect of
various factors defining activity of manganese systems on their properties was analyzed. The best carrying agent
for the catalytic system under study was chosen, and the optimal contents of an active component and a promoting
additive providing a high yield of С hydrocarbons were determined.
2
DOI: 10.1134/S1070427213030282
In last years natural gas attracts increasing attention as
an alternative source of raw material for obtaining various
products. The methods of processing natural gas realized
in industrial scale are based on complicated multistage
processes proceeding at high temperatures and pressures.
in presence of a catalyst. The most active catalysts of the
process are oxides of transition and rare-earth metals, and
also tin and lead oxides.
In this work we have studied supported manganese
catalysts, as manganese oxides in the pure state function
as deep-oxidation catalysts. Furthermore, supported
catalysts have a higher mechanical strength that allows
the research to be carried out in various hydrodynamic
conditions.
The main component of natural gas is methane. Two
main directions of methane processing can be distin-
guished: a direct conversion into products and an indi-
rect, which usually involves a preliminary production
of synthetic gas. Such widely used industrial processes
as the synthesis of methanol and ammonia, and also
the Fisher–Tropsch process, the MTG process of the
Samples of the catalysts were prepared by impregnat-
ing particles of the porous carrying agent by manganese
nitrate solution with added sodium compounds as pro-
moters and by the subsequent drying and calcination.
TheASKG silicagel, aluminum oxide, and a NaX zeolite
were used as carrying agents. Properties of the carrying
agents in use are presented in Table 1 and compositions
of the prepared catalysts, in Table 2.
“
Mobile” corporation, and some others [1] can serve as
examples of the indirect methane conversion. However,
single-stage methods, in particular the oxidative coupling
of methane to ethane and ethylene (OCM) seem to be
more rational.
The OCM process is an alternative to the existing
process of ethylene production by pyrolysis of the pet-
rol fraction, as the need for engine fuels obtained from
petroleum grows every year.
Catalytic properties of the prepared systems were
studied on a flowing-type lab scale unit with a fixed-bed
catalyst. The experiments were carried out using a quartz
reactor. The air and methane feed rates were controlled
by differential pressure flowmeter.
As is known [2], the oxidative dimerization of methane
represents the reaction of two СН molecules in presence
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of oxygen or another oxidizing agent with the formation
The catalyst loading was 10–40 cm and particle size
of С hydrocarbons. The process proceeds under atmo-
spheric pressure in the temperature range of 600–900°С
of the catalyst, 0.5–3.0 mm. The catalyst was arranged on
a punched quartz lattice located in the zone of a furnace
2
4
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