Russian Journal of Applied Chemistry, 2010, Vol. 83, No. 4, pp. 611−615.
Pleiades Publishing, Ltd., 2010.
Original Russian Text
A.G. Morachevskii, T.V. Butukhanova, 2010, published in Zhurnal Prikladnoi Khimii, 2010, Vol. 83, No. 4, pp. 559−563.
OF SYSTEMS AND PROCESSES
Thermodynamic Properties of Dilute Solutions
of Antimony in Liquid Lead
A. G. Morachevskii and T. V. Butukhanova
St. Petersburg State Polytechnical University, St. Petersburg, Russia
Received December 29, 2009
Abstract—Various methods of assessing the limiting activity coefﬁ cient of antimony and the area of the Henry’s
Law holding in liquid alloys of antimony–lead system were considered.
In processing of basic types of secondary lead-mate-
rials: worn-out lead-acid batteries, a dominant impurity
is antimony that is removed mainly by pyrometallurgical
methods [1, 2]. Information about the thermodynamic
properties of dilute solutions of antimony in liquid
lead is important for an analysis of equilibrium of such
Sb –Pb system is eutectic, the thermodynamic prop-
erties of liquid alloys of antimony with lead have been
studied repeatedly by various methods, but special studies
of dilute solutions of antimony in liquid lead were not
carried out. The results of the early works (before 1970)
were summarized in the handbook of Hultgrena et al.
, a number of studies [4–7] was made in later years.
EMF method was used with molten [4–7] or solid 
electrolyte, calorimetric measurements were carried out.
The activity coefﬁ cient of antimony at inﬁ nite dilution
(limiting activity coefﬁ cient γ
, component 1 antimony)
on the basis of experimental data on the integral molar
excess Gibbs energy ΔG
of system Sb–Pb can be cal-
culated either by a simple graphical calculation, or with
the aid of description in a form of analytical dependence
), where x
is molar fraction of antimony in
the liquid alloy Sb–Pb, and of subsequent differentiation:
From general relationship that connects the partial and
integral thermodynamic functions follows
With a simple transformation we can show that
Thus, an ordinate of the intersection point of curve
) at concentration area boundary x
= 0 gives limiting values of (ΔG
1 by which we can calculated the limiting value of the
activity coefﬁ cient of this component . If necessary the
correspondent values for component 2 can be calculated
by the same technique.
Dependence of ΔG
on the composition of system
Pb–Sb at 905 K is pictured according to data of  on
Fig. 1 and dependence ΔG
) is on Fig. 2.
According to equation (3) we get that RT ln γ
–1905 J mol
continuously rising powers, e.g.,
polinomials of Margules and Redlich–Kister  are the
most applicable for approximation of functions of mix-
ing in binary liquid systems of various origins. Margules
equation is of the following form
are empirical constant.