Russian Journal of Applied Chemistry, 2009, Vol. 82, No. 2, pp. 197−203.
Pleiades Publishing, Ltd., 2009.
Original Russian Text
A.G. Kasikov, A.M. Petrova, 2009, published in Zhurnal Prikladnoi Khimii, 2009, Vol. 82, No. 2, pp. 189−195.
AND INDUSTRIAL INORGANIC CHEMISTRY
Extraction of Rhenium(VII) with Aliphatic Alcohols
from Acid Solutions
A. G. Kasikov and A. M. Petrova
Tananaev Institute of Chemistry and Technology of Rare Elements and Mineral Raw Materials,
Kola Scientiﬁ c Center, Russian Academy of Sciences, Apatity, Russia
Received August 1, 2008
Abstract—Extraction of rhenium(VII) with C
aliphatic alcohols from HCl and H
examined. The rhenium(VII) distribution coefﬁ cients were examined in relation to the acidity and temperature.
The composition of the extracted complexes and the thermodynamic parameters of extraction were determined.
The extraction method of recovery and preconcentration of rhenium(VII) from H
solutions with secondary
octyl alcohol was tested in the counterﬂ ow mode.
Selective recovery of rhenium from solutions with
complex salt composition extensively utilizes liquid-
liquid extraction . Hydrometallurgical processing of
rhenium-containing raw materials in most cases produces
acid multicomponent solutions in which rhenium occurs
anion . Anions can be extracted with the
use of anion exchangers or neutral extractants. There
are published data on rhenium(VII) extraction with
various amines and quaterenary ammonium bases
[1–4]. Rhenium(VII) is efﬁ ciently extracted from acid
media with neutral organophosphorus compounds (TBP
(tributyl phosphate), alkylphosphine oxides [1–4])
and their derivatives (HBTA (hexabutyltriamide of
phosphoric acid), alkylphosphine sulﬁ des ) and analogs
(trioctylarsine oxide, trioctlyamine oxide ), various
synergistic mixtures (TBP + TOPO (trioctylphosphine
oxide), TBP + D2EHPA (di(2-ethylhexyl)phosphoric
acid), TBP + CMPO (carbamoylmethylphosphine oxide)
[3, 4]), as well as with neutral extractants such as ketones
and aliphatic alcohols [2, 4–9]. The latter received
inadequate attention, though they exhibit fairly high
distribution coefﬁ cients in rhenium(VII) recovery from
acid solutions [2, 5–9].
Aliphatic alcohols C
were ﬁ rst suggested as extract-
ants for rhenium(VII) recovery in the 1950s for analytical
purposes. More recently [5–8], extraction properties
of alcohols with higher molecular weights, promising
as commercial extractants for rhenium recovery, were
As regards their physicochemical properties, aliphatic
alcohols containing 7–10 carbon atoms in the hydrocarbon
chain satisfy the major requirements posed on commercial
extractants (poor solubility in aqueous phase, high ﬂ ash
point, low density, and low viscosity, which provides
for fast phase segregation, and chemical stability). In
extraction power with respect to rhenium(VII) alcohols
rank below amines and organophosphorus compounds,
but exhibit a higher selectivity and are less expensive
than such extractants .
Here, we examined the extraction properties of
aliphatic alcohols in rhenium(VII)
recovery from sulfuric and hydrochloric acid solutions.
As extractants we used higher aliphatic alcohols
produced in Russia: 1-heptanol and 4-heptanol; 1-octanol
and DL-2octanol; 1-nonanol, 2-nonanol, 4-nonanol;
and 1-decanol and 4-decanol (all pure grade), as well
as “97.8%, for synthesis” 2-heptanol, 3-heptanol, and
3-octanol, available from foreign ﬁ rms, without further
dilution, if not speciﬁ ed otherwise. Table 1 lists the major
physicochemical properties of the extractants used.
Since aliphatic alcohols are able of extracting mineral
acids , the extractants were preliminarily saturated with
SO4 or HCl to prevent additional isolation of a mineral
acid in the course of rhenium(VII) extraction from acid