ISSN 1070-4272, Russian Journal of Applied Chemistry, 2015, Vol. 88, No. 4, pp. 693−698. © Pleiades Publishing, Ltd., 2015.
Original Russian Text © T.A. Kenova, I.S. Vasil’eva, V.L. Kornienko, 2015, published in Zhurnal Prikladnoi Khimii, 2015, Vol. 88, No. 4, pp. 646−651.
Solution of problems of environment protection
and potable water saving requires the development of
efﬁ cient and environmentally safe methods for treatment
of industrial wastewaters to remove anthropogenic
Wastewaters from the majority of industrial enterprises
contain highly toxic components such as cyanides, thio-
cyanates, simple and complex ions of heavy metals (Cd,
Cr, Cu, Ni, Zn, Pb, etc.), and various organic impurities.
To reduce the concentration of metals in wastewaters,
various methods are used depending on the kind
and content of ecopollutants: chemical precipitation,
adsorption, ﬂ otation, membrane ﬁ ltration, electrochemical
treatment, and biodegradation [2–6].
Electrochemical methods are among the safest and
simplest methods for wastewater treatment to recover
valuable components, to eliminate harmful components,
including decomposition of the majority of organic and
inorganic impurities, and to remove heavy metal ions
The electrocoagulation method for wastewater
treatment is among such methods. It allows not only
the content of harmful impurities in the wastewater
to be considerably reduced, but also the secondary
contamination of the wastewater to be avoided. In
addition, the precipitate is formed in the course of
electrocoagulation in considerably smaller amount and
is more compact and better ﬁ lterable. It should be noted
that the electrocoagulation has also certain drawbacks, the
main of which are the need for replacing soluble anodes
and for increasing the electrical conductivity of solutions
in cases when it is insufﬁ cient [10, 11].
The electrocoagulation consists in the in situ
generation of the coagulant via electrochemical oxidation
of the soluble anodes, usually those made of iron or
aluminum, and formation of ОН
ions and hydrogen at
+ 2e, (1)
+ 3e, (2)
O + e
In the course of dissolution, the ions of these metals
undergo hydrolysis. The degree of hydrolysis depends
on the concentration of metal ions, pH of solution, and
concentration and chemical nature of the impurities
. The forming hydroxides occur in the solution in
Removal of Heavy Metal Ions from Aqueous Solutions
by Electrocoagulation Using Al and Fe Anodes
T. A. Kenova, I. S. Vasil’eva, and V. L. Kornienko
Institute of Chemistry and Chemical Technology, Siberian Branch, Russian Academy of Sciences,
Akademgorodok 60, str. 24, Krasnoyarsk, 660036 Russia
Received April 27, 2015
Abstract—Electrocoagulation treatment of model wastewater solutions to remove jointly present Cu
ions was studied. The inﬂ uence of the current density, concentration of impurities, anode material, and structure of
the precipitate of coagulant metal hydroxides on the efﬁ ciency of removal of the heavy metal ions was examined.
The decisive factor under the chosen process conditions is the anode material. The electrocoagulation efﬁ ciency
is considerably higher when using the aluminum anode, compared to the iron anode.