Russian Journal of Applied Chemistry, 2012, Vol. 85, No. 5, pp. 776−781.
Pleiades Publishing, Ltd., 2012.
Original Russian Text © A.B. Isaev, Z.M. Aliev, 2012, published in Zhurnal Prikladnoi Khimii, 2012, Vol. 85, No. 5, pp. 776−781.
AND CORROSION PROTECTION OF METALS
Effect of Oxygen Pressure on the Electrochemical
Oxidation of Chrome Brown Azo Dye
A. B. Isaev and Z. M. Aliev
Dagestan State University, Makhachkala, Dagestan, Russia
Received April 20, 2011
Abstract—Electrochemical oxidation of Chrome Brown azo dye under high oxygen pressure was studied. The
effect of current density, pressure, and oxygen duration on the process rate and efﬁ ciency was considered.
Most part of water used in manufacture of textile
materials is consumed by dyeing-ﬁ nishing plants.
Manufacture of 1 ton f dyed products may yield up
to 50–430 m
of wastewater . Depending on the
type of a material being dyed and parameters of the
technological process, 5–50% of the initial amount of
the dye passes into wastewater. Finding their way into
water objects, dyes adversely affect aquatic organisms,
and, therefore, the coloration is one of the main
controlled parameters of wastewater. It should be noted
that maximum permissible concentrations of dyes in
water are comparatively low, 0.1 to 0.0025 mg l
According to , the dilution intensity (ratio) of
wastewater from a wool-spinner plant may vary within
the range from 1 : 25 to 1 : 4200; the content of suspended
substances, from 40 to 232 mg l
; chemical oxygen
demand (COD), from 252 to 2300 mg O
/L; and pH,
from 3.3 to 7.3. The most rational scheme for wastewater
discharge envisages an autonomous detoxication of the
highly concentrated sewage to eliminate organic dyes
(spent dyeing solutions).
Researchers’ attention is attracted by problems
associated with development of local puriﬁ cation plants
intended for a small production capacity, with preference
is given to various physicochemical techniques for
wastewater puriﬁ cation. Recently, particular attention has
been given to methods for electrochemical oxidation of
organic compounds by generating such oxidizing agents
as hydrogen peroxide, oxygen, and ozone. In particular,
technological processes for indirect electrochemical
oxidation of organic compounds by products of oxygen
reduction to active oxygen-containing species (O
. and HO
radicals, etc.) are being
intensively studied [4, 5].
In [6, 7], the destructive decomposition of such
organic compounds as phenol, cresol, catechol, quinone,
aniline, oxalic acid, and Amarant azo dye was studied in
weakly acid solutions in the presence of Fenton’s reagent
[Fe(II) + H
was generated by electrolysis
on a mesh glassy-carbon cathode at a current density
of 20 mA cm
. Because deep oxidation of organic
substances requires, depending on their concentration,
a gross energy expenditure, application of the
electrochemical method in which products of cathodic
and anodic processes are simultaneously involved in
oxidation has been economically substantiated [8–10].
The electrochemical detoxication of textile
wastewater containing various dyes is, in principle, a
practically implementable technique because wastewater
contains, together with dyes, various compounds raising
the electrical conductivity of wastewater [2, 11]. The
review  presents data on the existing electrochemical
techniques for detoxication of dye-containing wastewater.
Advantages of the electrochemical detoxication of dyes