Improved Process of Treating Permanganate of Potash to Produce a Spongy Porous Mass.
Year: 1890

page_text: Date of Application, 22nd Sept., 1890
Complete Specification Left, 20th July, 1891-Accepted, 19th Sept., 1891
PROVISIONAL SPECIFICATION.
Improved Process of Treating Permanganate of Potash to Produce
a Spongy Porous Mass.
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 produce a porous spongy mass containing a
large percentage of permanganate of potash available for use in the separating or
obtaining oxygen or nitrogen from atmospheric air, or for other purposes to
which it may be applicable.
According to my invention I thoroughly mix and incorporate a quantity of
permanganate of potash with a percentage of pure kaolin, sufficient to bind the
mass together, and enough water to form the whole into a paste.
The pasty mass is then formed into bricks or slabs or other forms desired and
then baked in a retort or oven until dry and hard, during the operation of drying
and baking.
Vacuum is applied to the retort or oven. The vacuum and heat causing the
vaporisation of the moisture contained in the substance and rendering the mass
sufficiently porous for practical purposes and to allow atmospheric air to permeate it.
The baked bricks or slabs may be used whole or broken up into suitable
fragments.
Dated this 19th day of September 1890.
JAMES HOWARTH PARKINSON.
COMPLETE SPECIFICATION.
Improved Process of Treating Permanganate of Potash to Produce
a Spongy Porous Mass.
1, 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 transform into a porous or spongy mass a
permanganate or manganate (such as the permanganate or manganate of potash or
permanganate or manganate of soda) which when heated give off oxygen thereby
becoming reduced to lower oxides of manganese and probably free alkali. The
resulting compound being somewhat complex it probably never wholly returns to
the condition of a permanganate or manganate. If this be so the lower oxide of
manganese mixed with free alkali might of course be used. For convenience and
increased porosity by subsequently liberating its oxygen I prefer to use a perman-
ganate which when heated especially under reduced pressure gives off oxygen and
again reabsorbs 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). Through this porous
or spongy mass air can easily pass and come in contact with a large surface of
the said permanganate. It is primarily designed for use in the separating of oxygen
from atmospheric air but may be used for other purposes for which it may be
found applicable.
It consists essentially in mixing the permanganate with kaolin or other similar

page_text: material and water into a pasty mass and then baking in a retort or oven until dry
and hard.
The invention will be fully described with reference to the annexed drawings in
which as an example a form of retort or stove is shown in which the mass of
permanganate may be baked and dried.
Fig. 1, is a sectional elevation.
Fig. 2, plan.
The retort or stove is formed with a number of shelves A upon which the
material may be placed in moulds or otherwise. The shelves are supported on a
spindle B by the collar b they are removable and may be lifted out singly or the
spindle and shelves may be lifted out together. The cover C is secured by bolts c
and an additional shelf A¹ is placed below the shelves A. The stove is heated by
a gas burner D the products of combustion passing off through the pipe E to the
flue F. The interior of the retort or stove is connected by a pipe G with an air or
vacuum pump by which a partial vacuum may be formed and the moisture drawn
off at as low a temperature as possible.
I take the permanganate and thoroughly mix or grind it together with a small
percentage of pure kaolin or porcelain clay or similar inert material which will not
affect or be affected by the permanganate or by heat. The amount of kaolin
should be just sufficient to bind the mass together when baked say about 15 per cent.
and the two are mixed together with water into a stiff paste. The pasty mass is
then moulded into brick slabs or other forms which can be easily handled and
placed in a temperature beginning at about 15° to 20° C. and gradually increasing
to about 100° C. for about 4 hours until hard and dry. During the operation of
drying and baking the pressure in the retort is reduced below the atmospheric
pressure by means of an air pump connected by the pipe G whereby the moisture
becomes vaporised assisted by the heat and is drawn off leaving a spongy porous
mass readily permeated throughout by air.
I find that the process is assisted by first heating the material in an aqueous
vapour so that the air and moisture may become expanded in the mass before being
drawn off for this purpose I place in the bottom of the retort about of a cubic
inch of water for each cubic foot of space in the retort or just sufficient to fill the
retort with aqueous vapour. The bricks or slabs of the pasty mass of permanganate
and kaolin are placed upon the shelves in the retort and the lid securely fastened
down with an air tight joint. All atmospheric air is then withdrawn by the air
pump and as perfect a vacuum as possible obtained to permit the water placed in
the retort and the moisture contained in the permanganate to vaporise at a low
temperature. By the expansion and vaporisation of the moisture in the mass
before being drawn off pores are formed throughout the interior of the mixture.
The communication with the vacuum pump is closed until and the heat gradually
applied until a pressure somewhat above that of the atmosphere is produced in the
retort by which time the water placed in the retort and the moisture in the mixture
is converted into vapour.
The temperature is maintained for about 30 minutes
until the clay has become partially set after which connection with the vacuum
pump is re-established until all vapour has been drawn off. The baking process
as before stated continues from 3 to 4 hours at a gradually increasing temperature.
The heating of the permanganate may drive off some of the oxygen as it
approaches its maximum temperature thus forming a still more porous and lower
oxide thereof which is capable again of taking up or absorbing oxygen.
Having now particularly described and ascertained the nature of the said
invention and in what manner the same is to be performed I declare that what
I claim is
1. The process of forming a spongy or porous mass from permanganate of
potash or soda or lower oxide of the same which consists in mixing the perman-
ganate into a pasty mass with kaolin porcelain clay or similar material and baking
hard and dry in a retort or stove in a partial vacuum substantially as described.

page_text: 2. A spongy porous mass produced from permanganate of potash or soda or
lower oxide thereof which can be readily permeated by air produced in the
manner substantially as described.
Dated this 18th day of July 1801
WM. P. THOMPSON & Co.,
6, Bank Street, Manchester, Patent Agents.