Russian Journal of Applied Chemistry, 2010, Vol. 83, No. 7, pp. 1176−1181.
Pleiades Publishing, Ltd., 2010.
Original Russian Text
T.E. Nikiforova, V.A. Kozlov, M.V. Rodionov, 2010, published in Zhurnal Prikladnoi Khimii, 2010, Vol. 83, No. 7, pp. 1073−1078.
INORGANIC SYNTHESIS AND INDUSTRIAL
The Characteristics of Sorption of Heavy Metal Ions
with a Protein Sorbent from Aqueous Media
T. E. Nikiforova, V. A. Kozlov, and M. V. Rodionova
Ivanovo State University for Chemical Engineering, Ivanovo, Russsia
Received April 28, 2009
Abstract—Equilibrium- kinetic properties of a protein sorbent with respect to Cu
, and Zn
ions were studied. The dependences of the degree of recovery of metasl on their structure and pH of the medium
Determination of sorption, ion-exchange, and com-
plexing properties of natural materials is urgent in terms
of expanding the range of sorbents for the puriﬁ cation of
aqueous solutions of different nature. Promising biosorbents
for heavy metals ions from aqueous media are various
products of vegetable and animal origin, including waste
from food industry and agricultural sector, characterized
by accessibility and low cost. Currently, there is interest
in determining the sorption properties of a wide variety
of biopolymeric materials of vegetable origin, such as
ﬂ ax, mustard, and soybean crush [1-3], grains, and wool
keratin [4, 5].
Natural materials sorb heavy metals from aqueous
solutions with varying degrees of recovery (50–90%),
which depends on the properties of the material (chemi-
cal composition, amount and accessibility of functional
groups, the degree of dispersion, speciﬁ c surface area,
and porosity) and on the properties of an aqueous phase.
To study the characteristics of heavy metal sorption with
biopolymeric sorbents from aqueous solutions and to
establish a possible mechanism of the process requires
information about the physico-chemical properties of
sorbents and aqueous media and data on the effect exerted
on the sorption equilibrium by such factors as the nature
of a metal, the composition and pH of the medium, and
The aim of this work is to establish quantitative rela-
tionships of the effect of pH of aqueous solutions on the
sorption of Zn (II), Cu (II), Ni (II), Fe (II) and Cd (II)
ions with a protein sorbent.
Natural sorbent must not contain water-, acid- and
salt-soluble components. The most stable forms of pro-
teins, i.e., keratin-containing proteins, should be used
as sorbents. Therefore, wool is a convenient object of
study, as in the composition it is almost a pure keratin
with a sufﬁ ciently large surface sorption. Wool keratin
belongs to water-insoluble ﬁ brillar sorbents.
We used in the study a wool ﬁ ber of the following
amino acid composition (% of the total amount): glycine
6.29, alanine 4.12, phenylalanine 2.12, valine 4.12, leu-
cine 5.85, isoleucine 2.44, proline 5.05, serine 8.66, threo-
nine 5.12, tyrozine 2.62, methionine 0.32, cystine 7.30,
arginine 19.10, lyzine 3.92, tryptophan 0.82, histidine
1.91, aspartic acid 4.38, glutamic acid 8.48, glutamine
6.73 ; Zn(II), Cu(II), Ni(II), Fe(II), and Cd(II) sulfates;
; all reagents were chemically pure.
The sorption kinetics was studied by the method
of limited solution volume . To obtain the kinetic
curves of sorption, samples (m = 0.1 g) of the sorbent
were introduced into test tubes, V = 10 ml of a metal
sulfate solution was added into each, and the mixtures
were stored for a period from 15 min to 24 hours. The
sorbent with the ﬁ ber structure was uniformly distributed