ISSN 1070-4272, Russian Journal of Applied Chemistry, 2014, Vol. 87, No. 4, pp. 434−438. © Pleiades Publishing, Ltd., 2014.
Original Russian Text © E.A. Spetsow, L.A. Nefedova, S.A. Lavrishcheva, 2014, published in Zhurnal Prikladnoi Khimii, 2014, Vol. 87, No. 4, pp. 440−445.
AND ION EXCHANGE PROCESSES
Chemisorption of Microimpurities of Nitrogen(II)
and (IV) Oxides in the Presence of an Excess Amount of Oxygen
E. A. Spetsow, L. A. Nefedova, and S. A. Lavrishcheva
St. Petersburg State Technological Institute (Technical University), Moskovskii pr. 26, St. Petersburg, 190013 Russia
Received January 13, 2014
Abstract—Chemisorbents and chemical absorbents synthesized by impregnation of a γ-Al
active components in the form of transition metal oxides and potassium salts of metallic acids are recommended
for application. The sorbents are intended for neutralization of microconcentrated nitrogen mono- and dioxides
from an oxygen-enriched medium. The synthesis parameters and physicochemical properties of the sorbents are
presented and the conditions of the most effective operation of each type of sorbents are speciﬁ ed.
Various industrial processes (welding, maintenance of
the rolling stock and fuel reservoirs and functioning of
nitrogen industry shops, thermal power plants, and cata-
lytic generators of artiﬁ cial atmosphere) are accompanied
by both local and general contamination of air in a work
station by toxic nitrogen oxides. However, lowering the
oxygen of NO and NO
) in the working-area atmo-
sphere to the maximum permissible concentration level
(2–5 mg m
) by organization of an inlet-and-exhaust
ventilation and by using the classical methods of absorp-
tion catching or selective catalytic reduction are, as a rule,
inefﬁ cient. The optimal solution to the given problem is
to include ﬁ lters of design containing a cartridge with
a high-efﬁ ciency adsorbent into the puriﬁ cation process.
The main industrial adsorbents for absorption of NO
are activated carbons, carbon ﬁ bers, and high-porosity
metal oxide systems [1–3]. NO and NO
adsorbed on these materials under the action of intermo-
lecular interaction (Van der Waals) forces of the orienta-
tion and induction types. However, at a substantial excess
of molecular oxygen relative to NO
the gas being puriﬁ ed, the selectivity of the adsorption
process with respect to O
is substantially higher. This
circumstance leads to a nearly full blocking of the active
surface and, as a consequence, makes impossible provid-
ing the required puriﬁ cation level.
It is known [4, 5] that CeO
properties and, combined with active sorbents of nitro-
gen dioxide (e.g., Mn, Cu, or FE oxides) in an oxygen-
enriched medium, can promote oxidation of NO delivered
from the gas ﬂ ow, with its simultaneous transition to the
state of a surface complex ﬁ rmly retained by chemisorp-
tion interaction forces.
The patent  suggested using potassium permanga-
nate that deposited onto an aluminum oxide support and
serves as an active oxidant of NO to NO
due to the high
reactivity of oxygen in the active phase. It was noted that
manganese present in the composition can exhibit sorp-
tion properties with respect to the product being formed.
A high chemical activity toward nitrogen oxides can
also be exhibited by other substances in whose presence
the activity of the surface oxygen in the lattice is enhanced
under the inﬂ uence of an alkali metal cation, e.g., in po-
tassium metavanadate [7, 8].
One of the most important texture characteristics
responsible for the efﬁ ciency of sorption materials is
the active surface area of a sorbent. It is possible to use
for this purpose a high-porosity support, e.g., γ-Al
with a large degree of accessibility of the inner surface
of pores in grains and with a low hydraulic resistance of
a stock bed.