Russian Journal of Applied Chemistry, 2012, Vol. 85, No. 2, pp. 317−320.
Pleiades Publishing, Ltd., 2012.
Original Russian Text © A.G. Morachevskii, T.V. Butukhanova, 2012, published in Zhurnal Prikladnoi Khimii, 2012, Vol. 85, No. 2, pp. 331−334.
Thermodynamic Properties of Dilute Solutions
of Selenium in Liquid Lead
A. G. Morachevskii and T. V. Butukhanova
St. Petersburg State Polytechnic University, St. Petersburg, Russia
Received December 19, 2011
Abstract—The activity coefﬁ cients and activities of selenium in liquid alloys of the Pb–Se system at low selenium
content were estimated from the available experimental data.
Doping of lead-based alloys with various elements is
widely used today for improving the service characteris-
tics of lead batteries . Thermodynamic substantiation
of electrochemical and intermetallic compound methods
for lead reﬁ ning in utilization of spent batteries requires
data on the activity coefﬁ cients of doping components
in their dilute solutions in liquid lead . In previous
papers, by mathematical processing of experimental data
available from the literature, we estimated the activity
coefﬁ cients of antimony , bismuth , and arsenic
 at their low content in liquid lead and recommended
the values of the activity coefﬁ cients of these elements
at inﬁ nite dilution. Here we consider the data available
from the literature on thermodynamic properties of liquid
alloys of the lead–selenium system and report the results
of calculations and graphical plotting for estimating the
activity and activity coefﬁ cient of selenium in dilute
solutions in liquid lead.
In the Pb–Se system, only one compound is formed,
PbSe (mp 1079°С), with a very narrow homogeneity area.
The eutectic from the lead side is practically degenerated.
Addition of selenium to lead sharply increases the liqui-
dus temperature: 682°C at 2.5, 752°C at 5, and 832°C at
10 at. % Se . In the selenium-rich part of the Pb–Se
system, there is an immiscibility area.
Experimental studies concerning thermodynamic
properties of liquid alloys of the lead–selenium system are
relatively few. Schneider and Guillaume  determined
by the emf method the lead activity in liquid alloys with
selenium along the liquidus line. The data they reported
furnish no information on the selenium activity in liquid
alloys in the lead-rich part of the system.
Calorimetric studies of liquid alloys of this system
have been reported [8–11]. Kotchi et al.  tabulated
the integral thermodynamic characteristics of formation
of lead–selenium alloys from the pure components in the
liquid state (1365 K, 0.05 ≤ x
≤ 0.50, x
is the atomic
fraction of selenium in the liquid alloy). In [7, 12], the
experimental data on the Pb–Se system were processed
within the framework of the regular associated solution
model. In the system, there are signiﬁ cant negative devia-
tions from the ideal behavior, associated with the presence
of PbSe structural groups in the liquid phase.
The most informative is review  summarizing the
results of experimental studies. In particular, data on the
partial molar enthalpy and entropy of lead and selenium
at 1360 K in a wide composition range are tabulated.
To estimate the activity coefﬁ cient of selenium in lead-
rich alloys (0 ≤ x
≤ 0.10), we used analytical presenta-
tion of the concentration dependence of the integral molar
excess Gibbs energy ΔG
in the form of Redlich–Kister
polynomials of various degrees  (component 1 is Se):
Q = ——– = x
(1 – x
)[b + c(2x
– 1) + d(2x