Russian Journal of Applied Chemistry, 2009, Vol. 82, No. 1, pp. 169−171.
Pleiades Publishing, Ltd., 2009.
Original Russian Text
A.S. Kireev, V.M. Mukhin, S.G. Kireev, V.N. Klushin, S.N. Tkachenko, 2009, published in Zhurnal Prikladnoi Khimii, 2009, Vol. 82,
No. 1, pp. 171−173.
Preparation and Properties of Modiﬁ ed Hopcalite
A. S. Kireev, V. M. Mukhin, S. G. Kireev, V. N. Klushin, and S. N. Tkachenko
Mendeleev Russian Chemical Engineering University, Moscow, Russia
Neorganika Ecological Research and Production Company Public Corporation, Electrostal’, Moscow region, Russia
Lomonosov State University, Moscow, Russia
Received April 8, 2008
Abstract—A procedure was developed for the modification of the manganese-oxide catalyst hopcalite GFG
allowing the new quality, water resistance of granules, to be reached. This procedure can be used for the reactivation
of the exhausted catalytic contact.
Industrial Russian manganese-oxide molded catalyst
hopcalite GFG based on manganese dioxide and copper
oxide  is widely applied to the oxidation of carbon
oxide and in some cases also to the decomposition of
residual ozone. To improve qualitative and operating
characteristics of the catalytic contact, both the technique
directed on perfecting the technology of its preparation
 and the methods involving the catalyst composition
modiﬁ cation are used. For example, the modiﬁ cation of
a binder results in increased strength of granules , and
the introduction of a NaA-type zeolite into GFG allows
increasing the protective power of the catalyst with
respect to carbon oxide by 25−30% .
In regard to the use of hopcalite as an ozone destructor,
in particular, in technologies of water puriﬁ cation and
ozone-involving water treatment, its application in this
ﬁ eld is restricted. This catalyst does not possess water-
resistance − on contact with condensed moisture GFG
granules are destructed. By this reason its operation
is possible only in dry air-gas flows or it requires
maintaining a reactor working temperature of no less
than 110−120°C .
Hopcalite GFG cannot be water-resistant as it is
produced with the use of bentonite clay as a binder,
whereas one of the best Russian ozone destructors
GTT contains  the aluminum-calcium cement talum.
However the catalytic mass in the form of a pasta with
a humidity of 30−33% consisting of manganese dioxide
and other hopcalite components in a mixture with talum
has such rheological properties, which exclude molding
of small granules (~1 mm in diameter) by the extrusion
The aim of this work was the search for ways of
making a water-resistant catalyst based on hopcalite
components, manganese dioxide and copper oxide, and
the study of its physicochemical properties.
We used calcium oxide in an amount of 15−20 wt %
as a binder for the preparation of the molded catalyst.
Granules of the resulting catalyst had water-resistance
and strength comparable with those of GTT, whereas
their activity in ozone decomposing was 0.94−0.97
compared to GFG. The most probable reason of such
activity reduction can be a change in the nature of active
catalytic centers resulted from their interaction with the
active material СаО, which is a solid base.
The compositions containing СаО are characterized
by long solidiﬁ cation periods, and the prolonged time
of holding up an intermediate product required to reach
the necessary strength can increase production costs.
To reduce the time necessary for reaching the required
strength of granules, we applied a standard technique:
the addition of the chemical accelerating agent NaCl in
an amount of 1.0−1.5 wt %. It resulted in the activity
reduction up to 0.88−0.93, which most probably is caused
by a reaction of active centers with sodium chloride.
Thus, despite of losses of 7−12% of the initial activity
in ozone decomposition, hopcalite GFG has gained