ISSN 1070-4272, Russian Journal of Applied Chemistry, 2008, Vol. 81, No. 8, pp. 1386–1389. © Pleiades Publishing, Ltd., 2008.
Original Russian Text © E.R. Guseinov, 2008, published in Zhurnal Prikladnoi Khimii, 2008, Vol. 81, No. 8, pp. 1307–1310.
Extraction Method for Purification of Industrial
To Remove Iron Impurities
E. R. Guseinov
Institute of Chemical Problems, National Academy of Sciences of Azerbaijan, Baku, Azerbaijan
Received July 25, 2007
Abstract—Extraction of iron from aluminate-alkaline solutions was studied in relation to the concentration of
the extracting reagent, 2-hydroxy-5-alkyl(C
)benzyldiethanolamine and the volume ratio between the
aqueous and organic phases. The re-extraction conditions were determined.
PROCESSES AND EQUIPMENT
OF CHEMICAL INDUSTRY
At present, extraction is the most important among
the best known methods used to concentrate and sepa-
rate metals from various complex compositions. The in-
tensive manufacturing application of the extraction
technique and the rather effective use of extraction
processes in a number industries recovery of precious
metals from industrial raw materials make profitable
and cost-efficient and enable development of rational
technological schemes for separation of metals with
close physicochemical properties, which is now a rather
topical issue for modern hydrometallurgy.
A promising field of hydrometallurgy is recovery
of metals from alkaline solutions. However, concentra-
tion of metals from solutions of this kind and their fur-
ther processing is rather labor-consuming and ineffi-
cient, which leads to loss of valuable components. In
addition, the lack of effective and available extractants
that could recover metals from strongly alkaline solu-
tions hinders wide use of the extraction technique for
recovery and concentration of metals from products
with a complex salt composition and, in particular,
from aluminate-alkaline solutions. This technique
could simultaneously solve a no less important prob-
lem of purification of the final product (alumina) to
remove iron impurities.
Thus, a search for, and synthesis of the most ac-
cessible extraction reagents and development on this
basis of sufficiently efficient and selective methods for
recovery and separation of metals from alkaline solu-
tions with a complex composition constitute a rather
topical task of extraction chemistry.
This communication reports results obtained in
studies of extraction purification of industrial alumi-
nate-alkaline solutions, formed in manufacture of alu-
mina to remove iron impurities present in these solu-
tions, to give a gallium concentrate and pure alumina.
A technological scheme that provides integrated proc-
essing of solutions with complex salt composition for
hydrometallurgical purposes was developed and sug-
One of the main impurities in gallium-containing
technological solutions is iron [1, 2], which is present
in oxidation states II and III, or in a mixture of these.
In most cases, the concentration of iron is many times
that of gallium [3, 4]. In the alkaline technique for pro-
duction of alumina from alunites or bauxites, there
is a special technological unit for purification of alumi-
nate-alkaline solutions to remove iron impurities.
Therefore, it is necessary to briefly analyze the level of
understanding of methods for purification of these so-
lutions, produced by alkaline treatment of basic ores in
manufacture of alumina.
At present, this process is performed using classi-
cal methods, which have a rather low efficiency and
fail to provide the required degree of purification of