Improvements, in Obtaining or Separating Oxygen from Atmospheric Air.
Year: 1890

page_text: Date of Application, 22nd Sept., 1890.
Complete Specification Left, 20th July, 1891-Accepted, 5th Sept., 1891
Improvements, in Obtaining or Separating Oxygen from
Atmospheric Air.
I, JAMES HOWARTH PARKINSON Urmston Manchester Compressed. Gas
Engineer do hereby declare the nature of this invention to be as follows:-
The object of my invention is to provide means whereby oxygen or nitrogen may
be obtained or separated from atmospheric air in such manner that they may, be
available commercially.
According to my invention, I first separate the moisture contained in atmospheric
air by means of refrigerators or suitable chemical or other substances contained
in. suitable receivers or purifiers or by other means such as: pressure, and, cold
producing liquefaction of the moisture and carbon dioxide, or I force or draw the
atmospheric air through suitable purifiers or receivers charged; with chemical' or
other substances such as lime, soda &c., capable of absorbing the carbonic acid gas
contained in the atmospheric air.
The mixed oxygen and nitrogen I then force under pressure into heated retorts
of suitable form containing a porous or spongy mass of permanganate of potash
which said permanganate of potash may be prepared according to the method
described in the Specification of my other Patent of even date, or by any other
method desirable.
This permanganate of potash will absorb the oxygen contained in, the atmospheric
air which is forced into the retorts. The nitrogen passing away to the atmosphere
again or into suitable receivers, as desired.
When the permanganate of potash has absorbed a sufficiency of oxygen, the
pressure of air is withdrawn from the retorts and vacuum, applied by means of a
suitable automatic arrangement.
The retorts may vary in, or be kept at an uniform regular temperature during
the operation or operations..
The vacuum causes the heated substance to yield up the oxygen it had absorbe.!
and this oxygen is, when sufficiently pure, carried to suitable receivers.
The process may then be repeated in a continuous manner the substances
contained in the retorts being used for a lengthened period of time without
renewal.
If desired a current of steam may be passed into the retorts, to, assist the
operation.
The apparatus may be arranged in any suitable manner most convenient..
Dated this 19th day of September 1890.

page_text: Improvements in Obtaining or Separating Ogygen from
Atmospheric Air.
I, JAMES HOWARTH PARKINSON, of Stretford, in the County of Lancaster,
Gas Engineer, 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 :-
:
The object of the invention is to provide for the separation of the oxygen
from atmospheric air in such a way that it may be available for commercial
purposes. Hitherto this has chiefly been done by means of an anhydrous oxide
of barium which under certain conditions is capable of absorbing the oxygen and
afterwards giving it off again.
.
My invention consists in the use of a permanganate or manganate in a porous
or spongy mass or condition (such as the permanganate or manganate of potash
or permanganate or manganate of soda) which when heated gives off oxygen
thereby becoming reduced to lower oxides of manganese and probably free alkali.
The resulting compound is somewhat complex, and probably never wholly returns
to the condition of a permanganate or manganate. This being so the lower
oxide of manganese mixed with free alkali and an inert material to render it
open or porous might of course be used. For convenience and increased porosity
(by subsequently liberating its oxygen) I prefer to use a permanganate which
when heated with advantage especially under reduced pressure or vacuum gives
off oxygen and again eabsorbs oxygen when in its presence under pressure
(probably forming with the alkali a manganate or other salt of manganese) which
will hereafter for the sake of description and brevity, be called permanganate.
When heated as stated above the permanganate gives off oxygen and on stili
further increasing the temperature to dull redness of say about 550° C. In the
presence of free oxygen under pressure it will again reabsorb oxygen which will be
subsequently given off by reducing the pressure assisted if desired by increasing
the temperature (a slight variation in temperature does not very materially affect
its chemical property either to absorb or yield its oxygen). The material being
in a spongy or porous condition will be readily permeated throughout with the air
which is drawn or forced into the retort in which it is heated.
The operation will be fully described with reference to the accompanying
drawings which are annexed in order to describe the best means now known to me
of carrying out the invention but the apparatus therein shown is not claimed
herein as it forms the subject matter of application for Letters Patent No. 9457
of 1891.
Fig. 1, general plan of apparatus or retorts in which the permanganate and
atmospheric air are heated and also the retort containing air used to regulate the
supply of gaseous fuel.
Fig. 2, elevation partly in section of retort.
Fig. 3, plan of single retort.
Fig. 4, sectional plan of retort on line x-x Fig. 2.
Fig. 5, general elevation showing relative positions of several parts of the
apparatus.
The atmosphere from which the oxygen is to be separated is first purified and
then passed into a retort or chamber to be heated, thence to other retorts or
chambers filled with the porous spongy mass of permanganate which absorbs the
oxygen and subsequently delivers it up again, the oxygen being drawn off and
collected in a suitable receiver.
The atmospheric air is purified and freed from moisture in any well known
manner such as by being passed through suitable chambers charged with quick
lime, sodium-hydrate, caustic potash, or other substance capable of absorbing

page_text: moisture, carbon dioxide, nitric acid, sulphurous-acid, sulphuric acid, or other
impurities contained in the air.
The retort A in which the purified air is heated and the retorts B and C in
which the permanganate is heated are placed in a chamber or furnace D and are
supported therein on girders E to which they are bolted by the lugs e. The whole
apparatus may be contained in an iron or steel or other casing supported on wheels
or rollers for portability if desired. The retorts are preferably placed vertical and
heated with gaseous fuel.
Each retort is preferably constructed with two chambers connected together at
the bottom, a diaphragm or division plate F extending down between them from
the top nearly to the bottom. Through each chamber of the retort an internal
flue passes. The heat thus coming in contact with a large heating surface helps
to maintain an uniform temperature as far as possible throughout the retorts and
their contents. For this purpose also I place spirally or in other position round
the walls of the flue f both in the flue and in the chamber of the retort
strengthening or conducting pieces f¹. The retort is closed by a lid F¹ held down
by bolts.
k.
The retorts A, B and C are set in the retort chamber D as shown in the general
plan in Fig. 1 the retort A. being utilised for the heating of the air before coming
in contact with the permanganate, the retort B being utilised for absorbing the
oxygen from the atmosphere by the permanganate, while in the retort C the oxygen
is being liberated and drawn off from the permanganate by which it had been
previously absorbed. The number or capacity of the retorts A, B and C may be
increased or decreased if desired.
The air is admitted through a perforated inlet rose G and pipe g to the air
pump H by which it is pumped and delivered to the air compressor or second
I wherein it is compressed to a considerable. extent. From the air com-
pump
pressing pump I the air passes to the purifiers J and K.
The retort A is connected to the purifiers J and K by the pipe a.
The retort A
is connected to the retort B by the pipe band to the retort C by the pipe c leading
through a three way valve M to the pipe a' the valve permits of only one pipe
being open to the retort A at the same time or if desired two valves may be use i
one of which will be closed while the other is open. The valve M is connected to
the piston rod o of a cylinder O, the piston in which may be actuated by steam,
air or other fluid or the valve M might be worked by other mechanical means.
In operation the retorts B and C are filled with a porous or spongy mass of
permanganate which may be prepared by mixing a permanganate with kaolin and
water and baking in an oven according to the method described in my Specification
of Patent of even date No. 14931 of 1890 or in any other suitable way so that air
can be drawn through it. Instead of charging the retorts with the permanganate
in the first instance they may if it were found practical be charged with a combina-
tion of lower manganese oxides and free alkali mixed with clay into a porous state
as under the influence of heat the permanganate in the retorts is reduced to a lower
state of oxidation. Or pumice stone or similar absorbent material may be saturated
with a solution of permanganate or with the lower oxides of manganese and the
retort charged therewith but I wish it to be understood that I prefer the perman-
ganate prepared by mixing and baking with kaolin as described in my Specification
of even. date. The retorts A, B and C are heated to a moderate temperature of
dull redness say about 550° C.
This permanganate when sufficiently heated gives off oxygen becoming reduced
to lower oxides of manganese and probably free alkali and while at a temperature o
dull redness about 550° C, in the presence of free oxygen under pressure will again
combine with or absorb the oxygen. Atmospheric air is drawn in by the pump H
through the perforated inlet G and delivered to the compressor I by which it is
forced into the purifiers J and K where it is freed-from-moisture-carbon-dioxide
and other impurities. The purified air is then forced into the retort A where it is
heated to a high temperature and from the retort A passes into the retort B through

page_text: the pipe.b. In, the retort Bithe atmospheric air comes, in contact with the heated
permanganate under considerable pressure. The permanganate absorbs the oxygen-
and the nitrogen escapes through the pipe P'and back, pressure valve S either, to
the atmosphere or to a receiver preferably first passing through, a fuel, economiser..
or, heat extractor P¹ thus imparting its heat to the gaseous fuel before being.
supplied to the furnace or it could be utilised for heating the air instead of or, in
addition to the retort A:
..
Whilst the air is being forced into the retort B the oxygen is being drawn, off
from the permanganate in the retort C by the vacuum pump R assisted as before
described by heat the oxygen passing away through the pipe Qand valves T and U,
and pipe to the gas holder. When the operation of forcing in, the air to the.
retort B where oxygen is being absorbed and drawing off oxygen from the retort C
has been carried on for. a sufficient length of time the valve Mis reversed, by, the
piston rod o and the direction of the current of air changed so, as, to pass, into the
retort C the valves T and U acting automatically to permit of the, oxygen which
has been' absorbed by the permanganate in the retort B being drawn off. At, the
same time as the piston rod o reverses the valve M the movement of the piston
rod of reverses the valves which admit the gaseous fuel and air to the furnace in
order to supply heat to the retort containing permanganate from, which the oxygen
is being withdrawn.
The piston in the cylinder, O is actuated by compressed air or steam and, the,
valves are operated by a connecting rod V from the disc V₁, being washers
on the valve rod v with which the cross head v1 comes in contact.
The process as herein described may be continued, over and over again, for a
lengthened period of time without renewal of the material the permanganate when
heated absorbing the oxygen from the air under pressure and giving off the oxygen
again when the pressure is reduced.
It will be evident that the process may be carried out in any suitable form,of
apparatus in which the permanganate can be heated to the required degree and into
which the air can first be forced into the retort at any required pressure, and the
oxygen be subsequently drawn off by reducing the pressure. but the apparatus
which is shown will I think be found most efficient the details, of, which are fully
described and protected by Letters Patent No. 9457 of 1891.
Having now particularly described and ascertained the nature of the said inven-
tion, and in what manner the same is to be performed, I wish it to be understood
that I am aware that it has been proposed to separate oxygen from atmospheric air
by forcing or drawing purified air under pressure through heated oxygen absorbing
material, and subsequently drawing off the absorbed oxygen by reducing the
pressure, therefore do not claim such as my invention except when carried out.
as liereinbefore described; but I declare that what I claim is :-
.1. In the manufacture or separation of oxygen from atinospheric air the use of
porous spongy mass of permanganate of potash or soda or lower oxides thereof
to absorb the oxygen and subsequently to liberate the same substantially, as
described.
2: The process of manufacturing or separating oxygen from atmospheric, air
which consists in forcing or drawing purified air under pressure, through, a spongy
or porous mass of permanganate heated to a high temperature, until the oxygenas
absorbed and then liberating or drawing off the oxygen thus absorbed by reducing
the pressure substantially as described.
Dated this 17th day of July 1891.
WM. P. THOMPSON & Co.,.
6, Bank Street, Manchester, Patent Agents