A NEW OR IMPROVED, MODE OF PRODUCING OXYGEN GAS AT THE ORDINARY TEMPERATURE OF THE AIR OR AT A HIGHER, TEMPERATURE
Year: 1870

page_text: LETTERS PATENT to Edward Thomas. Kirkpatrick, of Brussels, in
the Kingdom of Belgium, Doctor of Natural Science, for the
Invention of "A NEW OR IMPROVED, MODE OF PRODUCING OXYGEN GAS AT
THE ORDINARY TEMPERATURE OF THE AIR OR AT A HIGHER, TEMPERATURE."
Sealed the 1st November 1870, and dated the 6th May 1870.
PROVISIONAL SPECIFICATION left by the said Edward Thomas Kirk-
patrick at the Office of the Commissioners of Patents, with his
Petition, on the 6th May 1870.
I, EDWARD THOMAS KIRKPATRICK, of Brussels, in the Kingdom of
Belgium, Doctor of Natural Science, do hereby declare the nature of the
said Invention for "A NEW OR IMPROVED MODE OF PRODUCING OXYGEN GAS AT
THE ORDINARY TEMPERATURE OF THE AIR OR AT A HIGHER TEMPERATURE," to be.
as follows:
My Invention relates to a new or improved mode or process of
producing oxygen gas at the ordinary temperature of the air, or at an
higher temperature, reducing the cost of such production, and thereby.
enabling the said gas to be used for manufacturing and other purposes ;-
and my Invention consists in the addition of hydrated oxide or any:

page_text: hydrated salt or other hydrated compound of cobalt or nickel, or any
mixture of the said substances in a comparatively small proportion to
any soluble hypochlorite, such as hypochlorites of lime, of potassa, of
soda, of baryta, or magnesia (commonly known as chlorides of lime, of
potassa, of soda, of baryta, or of magnesia). The said compound or
compounds of cobalt or nickel coming in contact with the said hypo-
chlorite or hypochlorites are decomposed, giving rise to a black
precipitate of superoxyde in a hydrated state, which precipitate acting
on the said hypochlorate (or chloride of oxide) sets free the oxygen
contained in the said hypochlorite. The oxygen gas thus set free
escapes with effervescence, and may be collected in the same manner
as hydrogen or carbonic acid gases in a reservoir or gasometer. The
hypochlorite which I prefer to use for the production of oxygen is
hypochlorite of lime (chloride of lime), which may be manufactured
in a liquid state, or in the more usual form of powder, known as
bleaching powder. When liquid chloride of lime is used in my process
it should form as concentrated a solution as possible, so as to reduce as
much as possible the volume of liquid to be acted upon. When chloride
of lime is used in the state of bleaching powder, it should be made into
a milk by mixing with it a certain quantity of cold or warm water. The
proportion of water which I prefer to mix with the said bleaching powder
to make the said milk is from one to five parts (in weight of water to
one part in weight of chloride of lime. The chloride of lime or other
soluble hypochlorite having been introduced into a suitable vessel, as
herein-after described, I pour in the hydrated compound of cobalt or
nickel in solution or in suspension in water, and oxygen gas is thereby
evolved. I prefer to use compounds of cobalt rather than those of
nickel, as the action of the compounds of cobalt is more prompt and
effective, and a smaller quantity is necessary for the generation of
the gas, and amongst the cobaltic compounds I prefer when operating
on a clear solution the nitrate or chloride of cobalt, which may be used
in aqueous solution, but when operating on turbid solutions of hypo-
chlorites or a milk of hypochlorites, sulphates of cobalt may be used
with advantage.

page_text: negative element or acid so as to prevent the disengagement of chlorine,
but if not it is advisable to add lime to the solution of the cobaltic salt
or compound, and the mixture thus obtained, which contains precipitated
oxide or subsalts of cobalt, may be poured upon the chloride of lime in.
the vessel. When the evolution of gas has ceased the cobalt falls to the
bottom as a superoxyde, the supernatant liquid may then be drawn off and
a fresh quantity of liquid chloride of lime may be poured in, and
this process may be continued till the oxide has lost its efficiency. The:
same quantity of oxide will often decompose successive additions of
chloride of lime almost indefinitely, but when the said oxide has lost its
efficiency it may be readily restored by transforming the said oxide
(after separating it from the supernatant liquid by filtration or other-.
wise) into a salt in the usual manner, care being taken to avoid an
excess of acid in the said salt. When a turbid solution or a mixture of
bleaching powder with water has been used, the superoxide will neces-
sarily be intermixed with solid particles, but it may readily be separated
by adding to the mixture an acid (and I prefer hydrochloric acid) till it
assumes an acid reaction, the cobalt is then dissolved, and carbonate of
lime should afterwards be added till the acid is neutralized. The cobalt'
will now be in solution in the liquid, which may be drawn off, and the
cobalt precipitated therefrom by lime or by any of the precipitants
usually employed, which form soluble compounds with lime. If hydro-
chloric acid has been used as a solvent liquid, chloride of lime is a very
convenient precipitant. The precipitated cobalt may now be converted
into a salt, as above stated.
With respect to the proportion of cobaltic compounds which should.
be used to liberate the oxygen from a given quantity of chloride of lime,
I prefer that the compound of cobalt added to the chloride of lime
should be in such proportion as to contain from three to ten parts by
weight of metallic cobalt to every thousand parts by weight of chloride
of lime, marking 100 degrees of Gay Lussac's scale. Less may be used,"
but the evolution of gas will then be slower. A too large proportion.
of the cobalt should be avoided as the cobalt passes to the state of
superoxide at the expence of the oxygen of the chloride of lime, and if
equivalent proportions of cobaltic compound and hypochlorite were used"
chlorine would alone be evolved without any oxygen being given off.
The apparatus I employ for the production of oxygen gas according.
to my Invention consists in a reservoir or generator of suitable material,

page_text: and of size corresponding to the quantity of gas to be produced. In
the said generator is a suitable stirring apparatus, and the said generator
is provided with suitable apertures for the introduction of the materials
to be operated upon, and the 'removal of the residuum of the operation,
and it is fitted with suitable tubing to conduct the oxygen gas to a
gasometer or reservoir. As the oxygen gas escapes from the generator
to the gasometer it should if necessary be made to pass through a
trough containing milk of lime or any alkaline mixture in order to its
being completely purified. Oxygen gas may be produced by the means
herein-before described, at the ordinary temperature of the air, but if
desired, heat may be applied to the generator to accelerate the evolution
of the gas.
Though I have more particularly described the use of hydrated
compounds of cobalt and nickel, mixed with chloride of lime for the
production of oxygen gas, the other hypochlorites herein-before named
may also be treated in like manner by adding thereto hydrated com-
pounds of cobalt or nickel, and oxygen gas will be produced therefrom,
according to my Invention.
SPECIFICATION in pursuance of the conditions of the Letters Patent,
filed by the said Edward Thomas Kirkpatrick in the Great Seal 2
Patent Office on the 5th November 1870.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, EDWARD
THOMAS KIRKPATRICK, of Brussels, in the Kingdom of Belgium, Doctor
of Natural Science, send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her 2
Letters Patent, bearing date the Sixth day of May, in the year of our
Lord One thousand eight hundred and seventy, in the thirty-third
year of Her reign, did, for Herself, Her heirs and successors, give and
grant unto me, the said Edward Thomas Kirkpatrick, Her special
licence that I, the said Edward Thomas Kirkpatrick, my exccutors,
administrators, and assigns, or such others as I, the said Edward
Thomas Kirkpatrick, my executors, administrators, and assigns, should
at any time agree with, and no others, from time to time and at all
times thereafter during the term therein expressed, should and lawfully
might make, use, exercise, and vend, within the United Kingdom of

page_text: Great Britain and Ireland, the Channel Islands, and Isle of Man, an
Invention for "A NEW OR IMPROVED MODE OF PRODUCING OXYGEN GAS AT THE
ORDINARY TEMPERATURE OF THE AIR OR AT A HIGHER TEMPERATURE," upon the
condition (amongst others) that I, the said Edward Thomas Kirkpatrick,
my executors or administrators, by an instrument in writing under
my, or their, or one of their hands and seals, should particularly
describe and ascertain the nature of the said Invention, and in what
manner the same was to be performed, and cause the same to be filed
in the Great Seal Patent Office within six calendar months next and
immediately after the date of the said Letters Patent.
NOW KNOW YE, that I, the said Edward Thomas Kirkpatrick, do
hereby declare the nature of the said Invention, and in what manner the
same is to be performed, to be particularly described and ascertained in
and by the following statement thereof, that is to say :—
My Invention relates. to a new or improved mode or process of
producing oxygen gas at the ordinary temperature of the air or at a
higher temperature, reducing the cost of such productions, and thereby
enabling the said gas to be used for manufacturing and other purposes;
and my Invention consists in the addition of hydrated oxyde or any
hydrated salt or other hydrated compound of cobalt or nickel, or any
mixture of the said substances in a comparatively small proportion to
any soluble hypochlorite, such a hypochlorites of lime, of potassa, of
soda, of baryta, or of magnesia (commonly known as chlorides of lime,
of potassa, of soda, of baryta, or of magnesia). The said compound or
compounds of cobalt or nickel coming in contact with the said hypo-
chlorite or hypochlorites are decomposed, giving rise to a black precipitate
or superoxyde in a hydrated state, which precipitate acting on the said
hypochlorite (or chloride of oxide) sets free the oxygen contained in the
said hypochlorite. The oxygen gas thus set free escapes with effer-
vescence, and may be collected in the same manner as hydrogen or
carbonic acid gases in a reservoir or gasometer. The hypochlorite which
I prefer to use for the production of oxygen is hypochlorite of lime
(chloride of lime), which may be manufactured in a liquid state, or in
the more usual form of powder, known as bleaching powder. When
liquid chloride of lime is used in my process it should form as
concentrated a solution as possible, not marking less than fifteen
degrees Baumé, so as to reduce as much as possible the volume of liquid
to be acted upon. When chloride of lime is used in the state of

page_text: bleaching powder it should be made into a milk by mixing with it a
certain quantity of cold or warm water. The proportion of water which
I prefer to mix with the said bleaching powder to make the said milk is
from one to two, or at most, five parts in weight of water to one part in
weight of chloride of lime. The chloride of lime or other soluble
hypochlorite having been introduced into a suitable vessel, as herein-after
described, I pour in the hydrated compound of cobalt or nickel in
solution or in suspension in water, and oxygen gas is thereby evolved.
I prefer to use compounds of cobalt rather than those of nickel, as the
action of the compounds of cobalt is more prompt and effective, and a
smaller quantity is necessary for the generation of the gas, and amongst
the cobaltic compounds I prefer, when operating on a clear solution, the
nitrate or chloride of cobalt which may be used in aqueous solution, but
when operating on turbid solutions of hypochlorites or a milk of the
hypochlorite, sulphate of cobalt may be used with advantage. It is very
essential that the said cobaltic compound should not contain an excess
of acid, otherwise an equivalent quantity of chlorine would be evolved.
When a neutral cobaltic compound is used the free lime contained in
the chloride of lime generally suffices to saturate the negative clement
or acid so as to prevent the disengagement of chlorine, but if not it is
advisable to add lime to the solution of the cobaltic salt or compound,
and the mixture thus obtained, which contains precipitated oxyde or
subsalt of cobalt, may be poured upon the chloride of lime in the vessel.
When the evolution of gas has ceased the cobalt falls to the bottom
as a superoxide, the supernatent liquid may then be drawn off and a
fresh quantity of liquid chloride of lime may be poured in, and this
process may be continued till the oxide has lost its efficiency. The
same quantity of oxide will often decompose successive additions of the
chloride of lime almost indefinitely, but when the said oxyde has lost
its-efficiency it may be readily restored by transforming the said oxyde
(after separating it from the supernatant liquid by filtration or otherwise)
into a salt in the usual manner, care being taken to avoid an excess of
acid in the said salt. When a turbid solution or a mixture of bleaching
powder with water has been used the superoxyde will necessarily be
intermixed with solid particles, but it may be readily separated by a
adding to the mixture an acid (and I prefer hydrochloric acid) till it
assumes an acid reaction, the cobalt is then dissolved and carbonate of
lime should be added till the excess of acid is neutralized. The cobalt
will now be in solution in the liquid, which may be drawn off, and the

page_text: cobalt precipitated therefrom by lime or by any of the precipitants
usually employed which form soluble compounds with lime..
If hydrochloric acid has been used as the solvent liquid chloride of
lime is a very convenient precipitant. The precipitated cobalt may now
be converted into a salt, as above stated. With respect to the proportion
of cobaltic compounds which should be used to liberate the oxygen from
a given quantity of chloride of lime, I prefer that the compound of
cobalt added to the chloride of lime should be in such proportion as to
contain from three to ten parts by weight of metallic cobalt to every
thousand parts by weight of chloride of lime, marking 100 degrees of
Gay Lussac's scale; less may be used, but the evolution of gas will then
be slower. A too large proportion of cobalt should be avoided, às the
cobalt passes to the state of superoxyde at the expense of the oxygen of
the chloride of lime, and if equivalent proportions of cobaltic compound
and hypochlorite were used chlorine would alone be evolved without any
oxygen being given off.
}
The apparatus used for the production of oxygen gas according to my
Invention consists in a cylindrical or otherwise shaped reservoir or
generator of suitable material and of size corresponding to the quantity
of gas to be produced. In the said generator is a suitable stirring
apparatus, or it may be made so as to be capable of being shaken either
by vibrating on an axis supported in suitable bearings or otherwise, so as
to cause the ingredients to commingle and to avoid too great a formation
of froth. The said generator is provided with suitable apertures for the
introduction of the materials to be operated upon and the removal of the
residuum of the operation; it is fitted with suitable tubing to conduct
the oxygen gas to a gasometer or reservoir or directly for use. The
said generator may be made sufficiently strong to allow of the oxygen
gas being produced under pressure, and I have found that oxygen gas
produced according to my Invention at the ordinary temperature of the
air may be generated steadily so as to have in the generator a pressure
of ten and even fifteen atmospheres, the said gas being being ready for
immediate use, or it may be allowed to escape from the generator to a
gasometer or other receptacle, and if necessary it should be made to pass
through a trough containing milk of lime or any alkaline mixture
in order to its being completely purified.
Oxygen gas may be produced by the means herein-before described at
the ordinary temperature of the air, but if the generator be adapted to

page_text: produce the oxygen at a low pressure, heat may be applied without
inconvience.
Though I have more partieularly described the use of hydrated
compounds of cobalt and nickel mixed with chloride of lime for the
production of oxygen gas, the other hypochlorites herein-before named
may also be treated in like manner by adding thereto hydrated com-
pounds of cobalt or nickel, and oxygen gas will be produced therefrom
according to my Invention.
Having now described the nature of my Invention, and the means of
carrying the same into effect, I wish it to be understood that I do not
confine myself to the precise details herein-before described, as the same
may be varied without departing from the nature of my Invention; but
I claim as my Invention the improved mode or process of producing
oxygen gas by the use of hydrated compounds of cobalt or nickel mixed
with chloride of lime or other hypochlorite, substantially as herein-before
described.
In witness whereof, I, the said Edward Thomas Kirkpatrick, have
hereunto set my hand and seal, this Second day of November,
in the year of our Lord One thousand eight hundred and seventy.
EDWARD THOMAS KIRKPATRICK. (L.S.)