INORGANIC SYNTHESIS AND INDUSTRIAL
Russian Journal of Applied Chemistry, 2011, Vol. 84, No. 12, pp. 2029−2032.
Pleiades Publishing, Ltd., 2011.
Original Russian Text © S.N. Orlov, K.A. Burkov, M.Yu. Skripkin, 2011, published in Zhurnal Prikladnoi Khimii, 2011, Vol. 84, No. 12, pp. 1946−1949.
Adsorption of Copper(II) Ions from Aqueous Solutions
on Alumina Industrial Wastes
S. N. Orlov, K. A. Burkov, and M. Yu. Skripkin
St. Petersburg State University, St. Petersburg, Russia
Received August 25, 2011
Abstract—Equilibrium adsorption of copper(II) ions on red mud (alumina industrial wastes) modiﬁ ed by various
methods was studied. The effect exerted by the nature the modiﬁ er (NaHSO
, NaCl + HCl, and H
) on the
sorption activity of red mud was determined.
Increasing human pressure on the environment
dictates the need for more efﬁ cient resource use and
improving environmental safety. One of the most prom-
ising solutions to these problems is the use of waste of
one production for the treatment of a waste of the other
production. Thus, the red mud, alumina industrial wastes,
can be used for sorption of polluting chemicals from
The dumps of red mud, which is present in water as
suspension (pH 11–13), pose a serious threat to the eco-
sphere. By the data of 2010, global aluminum production
was 40.6 million tons, while the production of 1 ton of
aluminum yields from 1 to 2 tons of red mud . Evi-
dently, development of a method of red mud utilization
is very promising. Previously , the possibility of using
red mud as coagulant for puriﬁ cation of wastewater from
electroplating plants has been studied. In this study, the
use of red mud as sorbent is considered as another method.
An important step of preparing sorbent from industrial
waste is the choice of the chemical modiﬁ cation method.
In addition to increasing the sorption efﬁ ciency, such
modiﬁ cation must prevent further contamination of an
aqueous solution upon addition of a sorbent.
Previously, high sorption capacity of red mud with
respect to ions of cadmium, zinc, copper, phosphates,
ﬂ uorides, chlorophenols, and other pollutants has been
reported elsewhere [3–7]. Thus, we can state that red mud
is an effective sorbent for a wide number of chemicals.
This study deals with the sorption of copper (II) from
aqueous solutions on red mud
We studied the properties of red mud obtained at the
Boksitogorsk alumina plant. Its elemental composi-
tion in terms of oxides was %: SiO
2.9, CaO 27.2, and Na
O 6.6. Red
mud contained iron oxides (Fe
and, to lesser extent,
), perovskite (CaTiO
), calcium silicates (ε-CaSiO
O), and aluminosilicates (NaAlSiO
ers) as major phases. According to the thermogravimetric
analysis, red mud dried at 100°С contains no more than
17% of water.
We studied red mud modiﬁ ed by three different meth-
ods (a) sodium hydrosulphate, (b) mixture of sodium
chloride and hydroﬂ uoric acid, and (c) sulfuric acid. In the
ﬁ rst method (a) to red mud (25 g of dry powder), 5 g of
anhydrous salt (NaHSO
), and 150 ml of distilled water
was added to pH 4.4; in the second method (b) 5 g of an-
hydrous NaCl, 150ml of distilled water, and concentrated
hydrochloric acid was added till neutral pH, and in the
third method (c) 42.5 ml of 2M of diluted H
ratio of sulfuric acid and red mass 1 : 3) and 107.5 ml of
distilled water was added.
The modiﬁ cation was performed at 35–45°С for 5 h at
continuous agitation. Then, the solution was ﬁ ltered and