Russian Journal of Applied Chemistry, 2010, Vol. 83, No. 8, pp. 1461−1465.
Pleiades Publishing, Ltd., 2010.
Original Russian Text
Yu.S. Chekryshkin, A.N. Chudinov, T.A. Rozdyalovskaya, A.A. Fedorov, 2010, published in Zhurnal Prikladnoi Khimii, 2010, Vol. 83,
No. 8, pp. 1355−1359.
The Oxidation of Zinc and Barium Chlorides with Oxygen
to Obtain Chlorine and Finely Dispersed Zinc Oxide
Yu. S. Chekryshkin, A. N. Chudinov, T. A. Rozdyalovskaya, and A. A. Fedorov
Institute of Technical Chemistry, Russian Academy of Sciences, Ural Branch, Perm, Russia
Received March 11, 2010
Abstract—The regular features of the reaction of calcium, barium, and zinc chlorides with oxygen to form
molecular chlorine and corresponding metal oxides are studied. The rate constants of the reaction were determined.
The effective activation energies of oxidation of chloride ions were calculated with due to regard for the diffusion
at the gas-chloride melt interface, which is especially pronounced at a temperature above 550°C. Zinc oxide being
formed was separated from the reaction mixture, and the dispersion of its particles was determined.
Little studies are available on the oxidation of halide
ions with oxygen. The reaction of sodium and potassium
chlorides with their metaphosphates in an air-argon ﬂ ow
at 800°C has been studied in . It was shown that no
chlorine is formed in the absence of oxygen in the system.
Kochergin, V.P. et al.  also showed that in the reaction
of sodium chloride with sodium metaphosphate oxygen
serves as oxidant. The reaction of Na(K)Cl with V
at 400–600°C in the presence of air yields chlorine and
sodium or potassium metavanadates [3–5]. In this case,
as oxidant for chloride ions serves oxygen. At the same
time, chlorine separation from a molten system in the
absence of oxygen also occurs via the reaction of sodium
chloride with V
with successive formation of vana-
dium bronzes and sodium metavanadate . In addition
to alkali metal metavanadates and V
, transition metal
oxides serve as catalysts in the reaction of oxidation of
chloride ions with oxygen in molten sodium, calcium,
and zinc halides , with their activity correlating with
the polarization force of the oxide cation .
Certain metal chlorides react with oxygen in the ab-
sence of catalysts. For example, the method of chlorine
formation via the oxidation of calcium chloride with oxy-
gen at 800°С has been suggested in , whereas calcium
oxide forming therewith was not separated.
It was established  that above 400°С zinc chloride
reacts with air oxygen to yield chlorine and the effect of
transition metal oxides on the reaction was determined.
In addition to the control of chlorine amount separated
from molten ZnCl
, the forming zinc oxide was separated
and its purity and dispersion was determined. Zinc oxide
is a multifunctional semiconducting material, attracting
attention of researches as promising catalyst [10, 11],
luminophore, and a constituent of light-emitting diodes
. The preparation of zinc oxide ﬁ lms by the oxidation
of zinc chloride with oxygen at 400°С under decreased
pressure has been described in . Therefore, the study
of the conditions of the zinc oxide synthesis and the
development of methods of its preparation are urgent.
The study is concerned with the regular features of
oxidation with oxygen, including air oxygen.
The kinetic regularities of the formation of chlorine and
zinc oxide in oxidation of chloride ions as a function of
the type of gas (air or oxygen) upon bubbling through the
melt, temperature, and presence of V
We used ZnCl
(both pure grade). An
amount of the separating chlorine was determined io-
dometrically . The oxidation was performed within
450–650°C, the air or oxygen was bubbled through the
melt or passed over its surface at a rate of 5 l h
error in determining the amount of the forming chloride