INORGANIC SYNTHESIS AND INDUSTRIAL
Russian Journal of Applied Chemistry, 2011, Vol. 84, No. 7, pp. 1152−1157.
Pleiades Publishing, Ltd., 2011.
Original Russian Text © I.V. Sheveleva, V.V. Zheleznov, S.Yu. Bratskaya, V.A. Avramenko, V.G. Kuryavyi, 2011, published in Zhurnal Prikladnoi Khimii,
2011, Vol. 84, No. 7, pp. 1080−1085.
Sorption of Cesium Radionuclides with Composite
Carbon Fibrous Materials
I. V. Sheveleva, V. V. Zheleznov, S. Yu. Bratskaya, V. A. Avramenko, and V. G. Kuryavyi
Institute of Chemistry, Far-Eastern Branch, Russian Academy of Sciences, Vladivostok, Russia
Received July 27, 2010
Abstract—Sorption of composite sorbents produced by a combined method of thermal treatment and electrochemical
and chemical deposition of transition metal ferrocyanides stabilized with latex emulsions onto a ﬁ brous carbon
matrix for cesium radionuclides was studied.
Liquid radioactive wastes (LRW) are formed at all
stages of the operation of any facilities intended for
mining, processing, or use of radioactive materials. The
puriﬁ cation of signiﬁ cant amounts of concentrated LRW
is one of the most pressing environmental problems.
having a long half-decay period (30 years) and provid-
ing a major contribution to the gamma-radiation dose of
radioactive wastes is one of the most environmentally
hazardous radionuclides in concentrated LRW. The most
efﬁ cient method for recovery of
Cs from radioactive
solutions is the sorption method, which can make the
volume of radioactive wastes tens and hundreds of times
smaller [1, 2]. Different sorption materials (natural and
synthetic ion exchangers and complexing, modiﬁ ed, and
composite sorbents) are used for recovery of cesium radio-
nuclides from aqueous solutions . Hexacyanoferrates
of transition metals, stable in a wide range of pH at high
salt concentrations and resistant to ionizing radiations,
have high afﬁ nity for cesium. However, a common dis-
advantage of all types of ferrocyanide sorbents is partial
peptization, especially at high pH. This gives no way to
reach the degree of solution puriﬁ cation that corresponds
to the actual selectivity of ferrocyanide crystals with
respect to cesium radionuclides. Development of selec-
tive sorbents with transition metal ferrocyanides ﬁ xed in
a porous matrix (natural clinoptilolite, synthetic zeolites
and aluminosilicates, granulated carbons, and activated
carbon ﬁ bers) leads to an increase in the degree of solution
puriﬁ cation from
Cs at a simultaneously lower con-
sumption of sorbents [1, 2, 4 ]. Recently, ﬁ brous sorbents
possessing better kinetic characteristics than conventional
granulated sorbents are increasingly used [4, 5].
An important problem in obtaining ferrocyanide sor-
bents is ﬁ xing metal salts on the surface or in pores of
the support. This problem may be solved by forming a
ﬁ lm of acrylic acid derivatives (siloxane-acrylate latex)
on the surface of the carbon matrix.
The modiﬁ cation of a ﬁ brous surface with a polymeric
ﬁ lm not only leads to reinforcement of the ﬁ ber , but
also causes stabilization of metal ferrocyanide particles
deposited onto the surface of the matrix. Equally impor-
tant is the dispersion of deposit on the support surface.
Nanosize crystals of metal ferrocyanides provide the best
kinetic characteristics of the sorbent when recovering
cesium radionuclides. Fine transition metal ferrocya-
nide particles on the surface of a carbon matrix may be
obtained, for example, by the introduction of additives
(aluminum salts) upon synthesis of composite materials
. The use of core-shell microemulsions constituted of
copolymers of polyacrylic acid and siloxanes as microre-
actors is another way of synthesis of nanosize structures.
A method for synthesis of nanosize sorbents selective to
cesium by using latexes containing polyacrylic acid was
suggested in . A combination of different methods to
the synthesis of transition metal ferrocyanides selective
for cesium stimulates the development of composite ma-
terials suitable for puriﬁ cation of liquid radioactive waste.