1070-4272/05/7807-1096+2005 Pleiades Publishing, Inc.
Russian Journal of Applied Chemistry, Vol. 78, No. 7, 2005, pp. 1096 !1100. Translated from Zhurnal Prikladnoi Khimii, Vol. 78, No. 7,
2005, pp. 1117!1121.
Original Russian Text Copyright + 2005 by Golovashin, Lazarev, Mamontov.
PROCESSES AND EQUIPMENT
OF CHEMICAL INDUSTRY
Kinetic Characteristics of Reverse-Osmosis Separation
of an Aqueous Solution of Aniline in a Flat-Frame Apparatus
V. L. Golovashin, S. I. Lazarev, and V. V. Mamontov
Tambov State Technical University, Tambov, Russia
Received April 5, 2005
Abstract-Reverse-osmosis separation of an aqueous solution of aniline on a flat-frame reverse-osmosis
installation was studied for two types of industrial polymeric membranes in relation to the concentration and
pressure of the solution in the intermembrane channel. The behavior of the main kinetic characteristics of
separation was analyzed and explained for different physical conditions of the process.
The goal of this study was to examine membrane
methods in separation of aqueous solutions of low-
molecular-weight organic substances in manufacture
of intermediates of organic synthesis and in treatment
of wastewater from chemical and related plants. An
aqueous solution of aniline, which is present in many
kinds of industrial solutions and wastewater from
production of dyes, served as a model.
Our studies were aimed to reveal the influence
exerted by the concentration of a solute and the pres-
sure on the specific flux of a solvent and on the reten-
tion factor of the membranes. The experiments were
performed on an installation with a closed circulation
of the solution in a two-chamber cell of the flat-frame
type with industrial composite membranes of MGA-
95K and OPM-K brands (manufactured by Vladipor
Joint-Stock Company, Vladimir, Russia). The flow
velocity of the solution in the intermembrane channel
was 0.4 m s
, and the solution temperature, 22oC.
The model solution was prepared using aniline of pure
grade and distilled water. The experiments were per-
formed using the procedure and apparatus described
The retention factor of membranes depends on
a large number of factors (material of a membrane,
nature of a solute and its concentration, working pres-
sure, temperature, hydrodynamic situation over the
membrane, etc.)  and is an integral quantity.
The dependences of the retention factor of the
membranes on the concentration of the solution under
study and on the working pressure are shown in
Fig. 1. It can be seen that the aniline retention factors
and the trends in their variation with the solution con-
centration strongly differ for the membranes studied
(MGA-95K and OPM-K) and have negative and posi-
Fig. 1. Retention factor K of (a) MGA-95K and (b) OPM-K
membranes for an aqueous solution of aniline vs. pressure
P. Concentration of the starting aniline solution (kg m
(1) 0.507, (2) 3.85, (3) 7.0, (4) 9.63, and (5) 14.18; the
same for Fig. 2.