ISSN 1070-4272, Russian Journal of Applied Chemistry, 2008, Vol. 81, No. 3, pp. 415!419. + Pleiades Publishing, Ltd., 2008.
Original Russian Text + T.E. Nikiforova, V.A. Kozlov, 2008, published in Zhurnal Prikladnoi Khimii, 2008, Vol. 81, No. 3, pp. 428!433.
OF SYSTEMS AND PROCESSES
Sorption of Copper(II) Ions with Soybean Crush Modified
with Sodium Monochloroacetate
T. E. Nikiforova and V. A. Kozlov
Ivanovo State University of Chemical Technology, Ivanovo, Russia
Received April 9, 2007
Abstract-The effect of chemical modification on sorption properties of soybean crush with respect to
copper(II) ions was examined. The optimal parameters of soybean crush treatment with sodium monochloro-
acetate to ensure the maximal sorption capacity of the sorbent were determined.
Various vegetable products can be promising sorb-
ents for recovery of heavy metal ions from aqueous
solutions, since they are cheap and renewable raw ma-
terials [1, 2]. The main drawback of such sorbents is
their comparatively low sorption capacity. Therefore,
modification of unconventional materials containing
protein and cellulose components to increase their
sorption capacity is an important step in preparation
of new sorbents. Various methods of modifying cellu-
lose-containing polymers (including mechanical,
physical, chemical, mechanochemical, and physico-
chemical methods) were suggested . The main
goal of such modification is to increase the internal
adsorption surface area and accessibility of the active
groups, and also to form new sorption-active groups
on the sorbent surface.
The chemical modification of secondary products
from treatment of oil-bearing crop seeds (sunflower,
flax, mustard, soybean, rape), formed in a large
amount (> 40%) in the course of vegetable oil making,
shows much promise.
In spite of available data on using soybean crush
, the possible presence in it of certain sub-
stances dangerous for human and animal health ex-
cludes its use as food and fodder without additional
treatment. Therefore, utilization of secondary products
from oil crop treatment is of interest in view of the
development of resource-saving processes. One of
possible directions of soybean crush and mill cake use
is the sorption treatment of aqueous solutions to re-
move heavy metal ions. An important requirement to
such sorbents is that they should not be the source of
secondary pollution for media to be purified.
The goal of this study is to prepare a new efficient
sorbent based on chemically modified soybean crush
containing chelating sorption centers for recovery of
copper(II) ions from aqueous solutions.
We used soybean crush of the following composi-
tion (wt %): crude protein 43.8, moisture 11.5, ashes
6.1, crude cellulose 5.6, fat 1.6, phosphorus 0.75, cal-
cium 0.24, total acidity 8.8, no toxicity , and
the following chemicals: CH
ClCOONa, NaOH or
, HCl or H
, and CuSO
chemically pure grade).
Initially soybean crush was ground and bolted
through sieves with mesh diameters of 1.0 mm to
separate coarse particles and 0.8 mm to separate fine
particles. Thus, the size of sorbent particles used
in the experiment was 0.831.0 mm. Samples were
air-dry; their moisture content did not exceed 14%.
Sorption of copper(II) ions was studied under static
conditions from aqueous solutions of copper sulfate
with stirring and thermostating at 293 K. The sorption
kinetics was investigated by the method of limited
solution volume. To obtain the kinetic curves of sorp-
tion, samples (m = 0.1 g) of the sorbent were in-
troduced into test tubes, V = 10 ml of copper sulfate
solution was added into each, and the mixtures were
stored for a period from 30 min to 24 h. The initial
copper ion concentration c
was 1.5 0 10
definite periods of time, the solution was separated
from the precipitate by filtration and the current cop-
per concentration c
in it was determined by atomic
absorption spectroscopy on a Saturn spectrometer.