ISSN 1070-4272, Russian Journal of Applied Chemistry, 2016, Vol. 89, No. 6, pp. 891−896. © Pleiades Publishing, Ltd., 2016.
Original Russian Text © A.A. Kushnir, P.T. Sukhanov, A.G. Savvina, L.P. Bondareva, E.V. Churilina, E.V. Poluzhenkova, G.V. Shatalov,
2016, published in Zhurnal
Prikladnoi Khimii, 2016, Vol. 89, No. 6, pp. 730−735.
INORGANIC SYNTHESIS AND INDUSTRIAL
Sorption of Aromatic Acids from Aqueous Solutions
by Polymer Based on N-Vinylpyrrolidone
A. A. Kushnir
, P. T. Sukhanov
*, A. G. Savvina
, L. P. Bondareva
, E. V. Churilina
E. V. Poluzhenkova
, and G. V. Shatalov
Voronezh State University of Engineering Technologies, pr. Revolutsii 19, Voronezh, 394036 Russia
Voronezh State University, Universitetskaya pl. 1, Voronezh, 394036 Russia
Received March 17, 2016
Abstract—Kinetic and equilibrium characteristics of the sorption of benzoic, salicylic and ortho-chlorobenzoic
acids by a new cross-linked sorbent based on N-vinylpyrrolidone were studied at various pH values of the me-
dium. It was found that the molecular sorption of aromatic carboxylic acids from aqueous solutions occurs in
the mixed-diffusion mode and the sorption capacity of the polymer grows with increasing acid-base equilibrium
constants of the acids. The advisability of introducing a salting-out agent into sorption systems was conﬁ rmed.
Effective sorption systems and a method for concentration of aromatic carboxylic acids from aqueous solutions
by the new cross-linked sorbent based on N-vinylpyrrolidone were suggested.
Aromatic carboxylic acids are widely used in
production of food products as conserving agents,
as dermatic antiseptic (antimicrobial) and fungicidal
(antimycotic) means in medicine, and in syntheses of
benzoate plasticizers (glycol, diethylene glycol, and
triethylene glycol esters), anthraquinone-oxazol dyes
(Vat red), and fragrant substances (salicylic acid esters).
However, excess amounts of any additives may lead to
allergic reactions and imbalance of active substances in
an organism; the sanitary regulations of various countries
control the content of aromatic carboxylic acids in food
products to below the admissible daily dose .
Because aromatic carboxylic acids are contained
in food and pharmaceutical products in microscopic
concentrations, the sorption is the most needed and
effective extraction method.
Of practical interest are polymeric sorbents based on
N-vinylpyrrolidone (NVP), which are characterized by
a high efﬁ ciency with respect to organic compounds of
various classes .
The goal of our study was to determine the funda-
mental aspects of the extraction of aromatic acids and
to develop a method for their concentration from dilute
aqueous media by a new cross-linked polymer based on
We used benzoic (BA), salicylic (SA), and ortho-
chlorobenzoic (CBA) acids puriﬁ ed by recrystallization
of commercial preparations and identiﬁ ed by their melting
points. Working solutions were prepared by dissolution
of precisely weighed portions of the starting substances
in distilled water.
The aromatic carboxylic acids were concentrated by
the sorbent (synthesized by the procedure described in 
at the chair of chemistry of micromolecular compounds
and colloids of Voronezh State University) produced
by radical copolymerization of a functional monomer,
N-vinylpyrrolidone, and a cross-linking agent, ethylene
glycol dimethacrylate (EGDMA), in the presence of a
polymerization-initiating agent (azo-bis-butyric acid
Chlorides and sulfates of sodium, potassium, and
ammonium (salting-out agents) were twice recrystallized