1070-4272/01/7404-0588 $25.00 C 2001 MAIK [Nauka/Interperiodica]
Russian Journal of Applied Chemistry, Vol. 74, No. 4, 2001, pp. 588!591. Translated from Zhurnal Prikladnoi Khimii, Vol. 74, No. 4, 2001,
Original Russian Text Copyright + 2001 by Zalevskaya, Radion.
AND ION-EXCHANGE PROCESSES
Sorption of Cations of the Zn
by Biomass of Ostreatus Agaricaceae Basidiomycete
) Cation Exchanger
T. L. Zalevskaya and E. V. Radion
Belarus State Technological University, Minsk, Belarus
Received February 3, 2000; in final form, October 2000
Abstract-Sorption of cations of the Zn
O system by the biomass of basidiomycete
(line 21 Pl. ostreatus f. florida) and by KB-4(H
) cation exchanger at pH 1.00 was studied. The results
are discussed with regard to the state of cations in the solution before contact with the sorbent, sorbent
properties, and sorption behavior of cations.
Previously, we studied the sorption of Cu(II), Pb(II),
Hg(II), or Fe(III) by the biomass of Pl ostreatus f.
florida basidiomycete from nitrate solutions contain-
ing a single cation or two metal cations simultaneous-
ly [1, 2]. The results were considered from the view-
point of hydrolytic properties of metal ions. Proceed-
ing with these studies, we examined the sorption of
Hg(II) by a basidiomycete biomass from 0.1 M solu-
tion in the presence of 0.1 M Zn(II).
To examine the nature of sorption bonds, we also
studied the sorption of Hg(II) and Zn(II) by carboxylic
cation exchanger KB-4(H
) whose functional groups
can act as centers of electrovalent interaction and are
able to participate in ion-dipole interaction, H-bond
formation, and complexation .
Analytically pure zinc nitrate and the solution of
Hg(II) nitrate prepared by dissolution of metallic
mercury in chemically pure nitric acid (1 : 1) were
used. The fruit bodies of basidiomycete Pl. ostreatus f.
florida, line 21 were provided by the Wood Institute,
Belarussian National Academy of Sciences. Samples
of air-dry basidiomycete biomass crushed to 0.5-mm
particles were brought in contact with metal salt solu-
tion in hermetically sealed vessels for one day. Pre-
liminary kinetic experiments showed that this the time
is enough for equilibrium to be attained in the system
. The required solution pH was adjusted by adding
chemically pure KOH or HNO
. The solution pH
was measured on an EV-74 universal pH meter with
an error of 0.05 pH units. In blank tests performed for
each system, a biomass sample was brought in contact
with a zinc- and mercury-free solution at a given pH.
Mixtures were kept in a TS-80 M-2 air thermostat
with intermittent agitation. After one day, equilibrated
solutions were separated from the basidiomycete bio-
mass, and the content of metal ions in them was de-
The cation exchanger was pretreated by the method
described in . Its moisture content, determined as
in , was 16.22%. The sorption was studied at 25 +
0.1oC under static conditions; the attainment of
the equilibrium distribution of metal ions between the
solution and cation exchanger was proved in all runs.
To determine the effect of metal ion concentration,
the sorption was studied at Hg(II) and Zn(II) concen-
trations of 0.01 and 0.1 M. The solutions prepared
were kept for 7 days at 25 + 0.1oC to attain equilib-
rium. The effect of pH could not be studied, because
HgO deposition begins even at pH > 1.20. Therefore,
all studies were done at pH 1.00.
The amounts of Hg(II) and Zn(II) simultaneously
present in the solution were determined complexo-
metrically. Initially the total metal content was de-
termined by back-titration with a standard solution of
zinc salt with eriochrome black T in ammonia buffer,
then potassium iodide was added to displace equiva-
lent amount of EDTA from its mercury complex, and
the displaced EDTA was titrated with the zinc salt.
The Zn(II) content in the mercury-free solution was