A New and Improved Process for the Production of Ozone.
Year: 1894

page_text: te of Application, 9th Oct., 1894-Accepted, 10th Nov., 1894
COMPLETE SPECIFICATION.
A New and Improved Process for the Production of Ozone.
We, JOHN THOMAS DONOVAN, Chemist, of 27 Athol Building, Springfield,
Massachusetts, United States of America, and HENRY LUNT GARDNER, Broker,
of 46 Florida Street, Springfield, Massachusetts, United States of America, do
hereby declare the nature of this invention, and in what manner the same is to
be performed, to be particularly described and ascertained in and by the following
statement:-
Our invention relates to a new and improved process for the production of ozone,
of which the following is a specification, reference being had to the annexed
drawing, which is a side elevation of a simple form of apparatus for carrying out
our invention.
The object of our invention is to provide a simple, cheap and effective process
for the production of ozone in large quantities; also to furnish a process which is
especially adapted for working in connection with electric currents from electric
light wires.
In carrying out our invention, we employ any electrolytic apparatus, with separate
but communicating chambers, for the generation of hydrogen and ozone, and insert
the positive and negative electrodes in the chambers, connecting them with an
electric generator of suitable power, and we arrange connections for removing the
hydrogen liberated from the negative electrodes, while the ozone generated at the
positive electrode escapes into the surrounding air, or it may, if desired be conveyed
away in a tube.
In producing ozone on a small scale, we may employ the ordinary apparatus like
that shown in the drawing, which consists of the tubes. A, B, connected by a cross
tube C. The tube A, has a wire a sealed in the bottom thereof, which is connected
with the electrode D contained in the tube, while the tube B, has a wire a' sealed
in the lower end thereof, which is connected with the positive electrode D'. The
upper end of the tube A is contracted to receive a flexible tube E for conveying
away hydrogen. In the present case the mouth of the tube B is flared to facilitate
the
escape of ozone.
In this electrolytic apparatus is placed a solution of permanganate of potassium
in water acidulated, for better conductivity, with sulphuric acid. The wires a, a,
are connected with an electrical generator F, and ozone and oxygen are immediately
evolved from the positive electrode D, in quantities varying with the size of the
electrodes, their distance apart, the strength of the current and the strength of the
electrolytic liquid.
We have found that the proportions of the permanganate of potassium and acid
may be varied and that the sulphuric acid may be replaced by nitric acid, hydro-
chloric acid, or a concentrated solution of chloride of sodium, without materially
affecting the results, the main requisite to the production of large quantities of
ozone being the presence of a permanganate such as permanganate of potassium.
We have found that permanganate of sodium, permanganate of silver, permanganate
of barium, and in fact any permanganate of a solid metallic base, can be used,
therefore we do not confine ourselves to permanganate of potassium. We have
found that the best results are obtained by using saturated solutions of permanganate
of potassium, and that the saturation may be maintained by the presence of crystals
of permanganate of potassium in excess in a five or ten per cent. solution of
sulphuric acid.
When a permanganate salt is used, such as permanganate of potash, the chemical
action which probably takes place during electrolysis, is the breaking up of a part

page_text: of the water into hydrogen peroxide, and the subsequent decomposition of hydrogen
peroxide and the formation of ozone in large quantity by one of the atoms of
oxygen in the permanganate.
This process we find gives us as much as 38 per cent. of ozone at the positive
electrode.
In defining our invention with greater clearness, we would state that we are aware
that it has been suggested that in electrolysis of water the addition of permanganic
acid is said to increase the proportion of ozone evolved.
It is, however, such an unstable compound that it is impracticable to use it, and
furthermore it tends rather to break up into the oxide of manganese, instead of
changing the peroxide of hydrogen into ozone, and we therefore make no claim
to the same, but confine our invention to a stable permanganate salt in this
connection, which not only may be practically used in a commercial way, but also
gives a different chemical re-action, for the permanganate salt (potassium perman-
ganate) undergoes no change, except to part with one equivalent of oxygen, which
goes into the hydrogen peroxide, and, when this is broken up by electrolysis, forms
ozone (03).
Having now particularly described and ascertained the nature of our invention,
and in what manner the same is to be perforined, we declare that which we
claim.is :
1. The process of generating ozone, which consists in submitting to electrolytic
action a solution of a permanganate of a solid metallic base in water, substantially
as and for the purposes described.
2. The process of generating ozone, which consists in submitting to electrolytic
action a solution of potassium permanganate in water, substantially as and for the
purpose described.
Dated this 12th day of September 1894.
JOHN THOMAS DONOVAN..
HENRY LUNT GARDNER.