AND POLYMERIC MATERIALS
Russian Journal of Applied Chemistry, 2011, Vol. 84, No. 2, pp. 295−300.
Pleiades Publishing, Ltd., 2011.
Original Russian Text © V.I. Grachek, A.A. Shunkevich, V.I. Martinovich, O.P. Popova, 2011, published in Zhurnal Prikladnoi Khimii, 2011, Vol. 84, No. 2,
Water-Soluble Polyelectrolytes Based on Polyacrylonitrile
for Wastewater Treatment
V. I. Grachek, A. A. Shunkevich, V. I. Martinovich, and O. P. Popova
Institute of Physical Organic Chemistry, National Academy of Sciences of Belarus, Minsk, Belarus
Received April 22, 2010
Abstract—The possibility of modifying oxidized asphalt by performing polycondensation of maleic anhydride
with aliphatic amines of various chemical structures in the dispersion medium was considered. The inﬂ uence of
the reactant structures and reaction conditions on the physicomechanical and structural-rheological properties of
the polymer-modiﬁ ed asphalt was examined.
Flocculants based on polyacrylonitrile derivatives
are widely used for treating industrial wastewaters and
intensifying separation of various natural dispersions
[1–3]. It is known that the ﬂ occulant performance is
determined not only by polymer characteristics, but also
by the wastewater composition . Because the amount
of pollutants in wastewaters is very large, commercial
ﬂ occulants do not always ensure efﬁ cient puriﬁ cation.
Therefore, new effective reagents for treating natural
and wastewaters should be sought for.
In this study we tested available water-soluble
polyelectrolytes based on wastes from production and
processing of Nitron ﬁ ber as ﬂ occulants for industrial
As raw materials for preparing polyelectrolytes (PEs)
we used “wet” wastes from production of Nitron ﬁ ber
at the Polimir Production Association (Novopolotsk,
Vitebsk oblast, Belarus), containing 92.5% acrylonitrile.
From ﬁ ber wastes, we synthesized various kinds of
polyelectrolytes: anionic (FA-1), amphoteric (AMF-2),
and cationic (FK-1, FK-3). The anionic polyelectrolyte
was prepared by hydrolysis of the wastes at 100–103°С
in an aqueous 5–12 wt % NaOH solution at pH 11–12.
As modiﬁ er we used ethylenediamine (EDA) taken in
an amount of 10% relative to the weight of the initial
Nitron ﬁ ber. The amphoteric ﬂ occulant was prepared by
two-step synthesis. The ﬁ rst step was amination of the
waste with 3-dimethylaminopropylamine (DMAPA),
and the second step was hydrolysis of the aminated ﬁ ber
with alkali . The cationic ﬂ occulants were prepared
by amination of wastes with EDA (FK-1) and DMAPA
(FK-3) at 100–115°С for 16–20 h until the ﬁ ber fully
dissolved. The structures of the ﬂ occulants obtained
were determined by IR and
H NMR spectroscopy [5,
6]. The exchange capacities of the anionic and cationic
polyelectrolytes were determined after the removal of
low-molecular-weight impurities and conversion into
the required form. PE weighed portions were titrated
potentiometrically with a 0.1 N NaOH solution for FA-1
and a 0.1 N HCl solution for cationic PEs . The static
exchange capacity (SEC) of the PEs was calculated from
the position of the inﬂ ection point (Fig. 1). The pH values
were measured with an I-130М pH meter. The static
exchange capacity of the amphoteric PE was determined
by the procedure described in . The intrinsic viscosity
[η] of PE solutions was determined with an Ubbelohde
viscometer at 20°С (d
= 0.56 mm). The characteristics
of the PEs studied are given in Table 1.
As seen from Table 1, the molecular weights of the