Russian Journal of Applied Chemistry, 2009, Vol. 82, No. 7, pp. 1317−1320.
Pleiades Publishing, Ltd., 2009.
Original Russian Text
A.G. Morachevskii, T.V. Butukhanova, 2009, published in Zhurnal Prikladnoi Khimii, 2009, Vol. 82, No. 7, pp. 1221−1223.
Interaction of Aluminum with Admixtures Dissolved
in Liquid Lead
A. G. Morachevskii and T. V. Butukhanova
St. Petersburg State Polytechnical University, St. Petersburg, Russia
Received May 25, 2009
Abstract—The behavior of antimony, tin, copper, bismuth, and arsenic admixtures during refining black lead
with aluminum application was considered.
One of possible methods of considerable reducing antimony
tent in lead obtained by processing secondary lead-
containing raw material, ﬁ rst of all scraps of lead batteries,
is the insertion of aluminum in molten metal with the
subsequent formation of the AlSb compound in the form
of a solid phase. The melting point of AlSb is 1058 ± 10°C,
and density, about 4.2 g cm
. The method is known
for a long time , but its thermodynamic substantiation,
including temperature process conditions, and also an
experimental veriﬁ cation of the fulﬁ lled calculations were
carried out rather recently [3, 4].
It was found that reﬁ ning secondary lead antimonide
(the initial antimony content about 2−3 wt %) with
aluminum is effective under the following operating
conditions: the temperature of aluminum input 690−720
and the duration of intermixing at this temperature up to
30 min, therewith the aluminum consumption can vary
over a wide range, but should be no less than 40% of
the weight of removed antimony . The recommended
subsequent rate of cooling up to the ﬁ nal temperature of
350°C is 5−6 deg min
. The antimony content in lead
can be reduced up to 0.005 wt %. Experimental studies
completely conﬁ rmed the thermodynamic analysis .
It is of interest to consider behavior of some possible
admixtures in secondary lead, namely, tin, copper,
bismuth, and arsenic during this process. The phase
diagram of the lead−aluminum−tin system at 650, 730,
and 800°C was studied by Davies rather explicitly .
This ternary system was also studied in other works [6,
7]. The systems Al−Sn and Pb−Sn belong to eutectic
systems, and the ternary system Pb−Al−Sn includes an
extensive phase separation area adjacent to the Al−Pb side
and somewhat decreasing as temperature increases.
Data on the distribution of tin small amounts between
aluminum and lead phases in liquid state are given in the
work of Pleva et al. . Unlike antimony removal by
adding aluminum, which belongs to intermetallic reﬁ ning
processes, in the case of tin the extracting separation
of metals takes place. It was shown in  that in the
temperature range of 700−900°C the coefﬁ cient K
tin distribution between aluminum and lead, expressed
as the ratio of mole fractions in coexisting aluminum (I)
and lead (II) liquid phases, is
= = 0.32 ± 0.04.
The same authors  noted that at a phase equilibrium
the mole fraction of lead in the aluminum layer x
not exceed 0.005, and the lead layer practically does not
In the other work  the distribution of components
between two not mixing phases in the system Pb−Al−Sn
was studied at higher tin contents in the temperature range
800−1020°C. Depending on the total tin content in the
ternary system its distribution coefﬁ cient between phases
I and II at 800°C expressed in terms of tin mole fractions
lays within the limits of 0.381−0.424.
At equilibrium tin activity in coexisting phases is the
, where γ