IMPROVEMENTS IN THE PRODUCTION OF ARTIFICIAL OXIDES OF MANGANESE, AND IN THE MANUFACTURE OF CHLORINE BY MEANS THEREOF, PARTLY APPLICABLE ALSO TO OTHER PURPOSES.
Year: 1867

page_text: LETTERS PATENT to Walter Weldon, of Park Villa, West Hill, Highgate,
in the County of Middlesex, for the Invention of "IMPROVEMENTS IN THE
PRODUCTION OF ARTIFICIAL OXIDES OF MANGANESE, AND IN THE MANUFACTURE
OF CHLORINE BY MEANS THEREOF, PARTLY APPLICABLE ALSO TO OTHER
PURPOSES.".
Sealed the 18th February 1868, and dated the 4th September 1867.
PROVISIONAL SPECIFICATION left by the said Walter Weldon at the
Office of the Commissioners of Patents, with his Petition, on the
4th September 1867.
I, WALTER WELDON, of Park Villa, West Hill, Highgate, in the County
of Middlesex, do hereby declare the nature of the said Invention for "IMPROVE-
MENTS IN THE PRODUCTION OF ARTIFICIAL OXIDES OF MANGANESE, AND IN THE
MANUFACTURE OF CHLORINE BY MEANS THEREOF, PARTLY APPLICABLE ALSO TO OTHER
PURPOSES," to be as follows:-
This Invention consists, firstly, in the employment of artificially ozonized
air for the peroxidation of the lower oxides of manganese, more especially
(though not solely) with a view to the conversion of precipitated protoxide of
manganese into a higher oxide, suitable for use for the liberation of chlorine
from bydrochloric acid, and for other purposes; and, secondly, in certain
details of apparatus and modes of proceedure, most of which said details

page_text: are applicable also when the peroxidation of the said lower oxides of
manganese is effected by means of ordinary or non-ozonized air. The
peroxidation of the lower oxides of manganese by means of ozonized air can
be performed either in the wet or in the dry way. When performing it
in the wet way I either inject ozonized air into a mixture with water,
solution of chloride of calcium, or other suitable liquid of the inferior oxide
convenient way.
I
When following the
of manganese which I desire to peroxidize, or in any
agitate the said mixture in contact with ozonized air.
first mentioned of these two methods, except in so far as I may use the
modifications of apparatus and proceedure which will be described below, I
proceed exactly as in the Specifications of two former Patents, numbered
and dated respectively No. 1948, July 26th, 1866, and No. 133, January, 18th,
1867. I have described for the peroxidation of protoxide and sesquioxide of
manganese by means of ordinary or non-ozonized air, with the addition that
before injecting the air into the mixture containing the oxide which I desire
to peroxidize I previously ozonize the said air by passing it through any
convenient apparatus adapted to effect that object. I do not claim any
particular form or kind of ozonizer, the part of my Invention of which I am
now treating relating solely to the new application of ozonized air, which
consists in the employment thereof in and for the peroxidation of the lower
oxides of mangenese, and not to the means or appliances whereby the
ozonization of the air so applied is effected. may state however that what
I believe to be the most convenient and advantageous of such appliances
for this purpose as are at present known are the "ozone generator," invented
by Mr. Edward Beanes, and a similar apparatus which I believe has been
invented, and which I am informed is about to be patented and made public,
by Mr. Tisley. When I follow the last mentioned of the two methods of
proceedure by the wet way I either pump (or otherwise lift or elevate) the
mixture of oxide and liquid from one level to a higher one, and then allow
it to fall through the air from the said higher level to its original or any
other convenient one, proceeding in this way continually until the lower
oxide has been sufficiently peroxidized; or I place the said mixture of oxide
and-liquid in any convenient churning apparatus, and mechanically "churn"
it until the desired end has been accomplished; or I place the mixture in
an open vessel of considerable depth in or near the centre, but having sloping
sides of large extent of surface, and then by means of any suitable paddle
wheel or wheels, or other mechanical appliance duly adapted to the deeper
part of the vessel, I agitate the mixture more or less violently, dashing i
about so as to bring all parts of it successively to the surface, and so as

page_text: constantly to fling portions of it on to the sloping sides of the vessel, by running
down which to the deeper part of the vessel its exposure to the air is
advantageously prolonged; or I combine together any two or more of these
methods. When following any of these methods of agitating in contact with
air a mixture of oxide of manganese with water or other suitable liquid,' or
any combination of two or more of them, I can either ozonize or not, as I
may prefer, the air in contact with which I agitate the said mixture; but.it
should be observed that whereas as regards the agitation of the said mixture
in contact with ozonized air I do not confine myself to the particular kinds
of apparatus which I specially indicate, my claim being for the ozonization of
the air in contact with which the mixture is so agitated, and for the process
of peroxidising the lower oxides of manganese, which consists in agitating a
mixture thereof with any suitable liquid in contact with air so ozonized; yet
as regards the agitation of the said mixture in contact with: ordinary air 'I
confine my claim to the particular methods of agitation specified. When
performing by the dry way the peroxidation of protoxide or other low oxide
of manganese I can operate according to circumstances, either in the cold
or 'at a furnace heat, or at any intermediate temperature. When employing
heat I can if using ozonized air operate in a reverberatory or other suitable
furnace, exactly as has been previously proposed by other Inventors, with the
addition simply of first ozonizing the air with which I supply the furnace, and
which I pass over the oxide heated in it; but I prefer under all circumstances
(and I wish it to be understood that when using ordinary air I confine myself
berennto), instead of passing over the oxide which is to be peroxidised a
mixture of heated air and heated products of combustion, which is what has
been done hitherto whenever it has been attempted to effect the peroxidation
in question, to treat the oxide, either simply with heated. air or with a mixture
of heated air and vapour of water. This can be done in any convenient
vessel or oven, perhaps the best plan however being to place the oxide
in a revolving cylinder, and to pass through that the requisite heated air
or mixture of beated air and vapour of water.
.
This part of my Invention is applicable not only to the production of per-
'oxide from protoxide or other low oxide of manganese, but also to. the
production of peroxide from carbonate of manganese. Very excellent results
may be got by treating hydrated protoxide of manganese with air or a mixture
of air and vapour of water at a temperature below that at which the protoxide
would lose its water of hydration; and it is also an improvement upon. the
plan of peroxidizing protoxide or other low oxide of manganese, by exposing
it in a furnace to a mixture of heated air and heated products of combustion

page_text: to add steam or vapour of water to the said mixture. When not employing
artificial heat, but operating in the dry way at ordinary temperatures,, it is
sufficient, when a very long time can. be allowed for the peroxidation, to
spread the protoxide thinly over a large surface, and simply, so. leave it in
contact with air, ozonized or not,. until the peroxidation shall have been
sufficiently accomplished; but I prefer in all such cases to. facilitate the
peroxidation by crushing the oxide, when, it has caked together, and so
keeping it from the time it is dry enough to take that form, in the state of
powder, and by then stirring into it and turning it over from time to time;
either by manual labour or by the aid of, suitable self-acting or other
mechanical appliances. The oxide may, when, preferred, be; spread over an
open field or other space; but when employing ozonized air it is of course
necessary to expose it under cover. A good plan is to put the oxide in a
slowly revolving cylinder, and to blow air through the said cylinder, if ozonized
air be employed; or to either blow the air through or draw, it, through by con
nexion with a chimney or otherwise; if ordinary air be used. Another plan
is to place the oxide in thin layers on trays (arranged, one above. another
in a room through which a, moderate current of air is kept passing by con
nexion with a chimney or by any other means. Another plan is to place the
oxide on the floors of shallow flues, through which a current is kept passing
as before. These flues may be constructed of either brick, or stone, or iron,
and in sets one above another, and from end to end of each, first in one
direction and then in the contrary, either a simple; strip of metal or a
roller furnished with one. or more such knife-like strips of metal may
be kept slowly travelling so as constantly to turn over the oxide and thereby
hasten. its peroxidation. (With obvious: modifications this last-mentioned
plan is available also when heat is employed.) Still another plan of
operating by the dry way at ordinary temperatures is to expose the oxide,
either under cover or in any open space, in heaps rendered as porous as
possible by admixture with pebbles, or with fragments of coke, brick,
stone, slag, or any other material which will serve to divide the mass,
while admitting of being readily separated from the peroxidized; oxide. A
similar admixture can also be used when the oxide is exposed, otherwise than
in heaps. The oxide can also be exposed in heaps.or otherwise in admixture
either with faggots or with tubes of porous earthenware,, and when these
last are used they can with advantage be furnished with numerous small
perforations.
When commencing with protoxide of manganese obtained by decom-
posing by means of lime the "still liquor" which remains after a more or

page_text: 'less rich peroxide of manganese has been digested with hydrochloric acid for
the liberation therefrom of chlorine it is desirable that the utmost care should
be exercised to use lime free from carbonate, and to have the lime in the finest
practicable state of division. It is a good plan to add the lime to the still liquor
in the state of milk of lime, and to either.grind this milk of lime in ja pug mill
or between rollers or otherwise, or else to separate all lumps and impurities from
it as far as possible by careful arrangements for their subsidence.. When the
peroxidation of the protoxide is performed in the wet way, and more especially
when it is effected by the injection of air, a small excess of lime may be used
with advantage. When performing, as. I. prefer, all the operations of, the
process in the chlorine stills themselves, the peroxide formed will be found to
settle within a few hours so completely that when the supernatant solution. of
chloride of calcium has been drawn off from it the oxide remaining will
dissolve with sufficient readiness in moderately strong hydrochloric acid; but
when an acid weaker than the oxide will then dissolve in is employed the
oxide may be partially dried, without removing it from the still, either by
injecting, a blast of hot air or by means of steam or hot air passed through
metal, stone, earthenware, or other pipes, suitably placed inside the still. Oxide
of manganese may also be heated with hydrochloric acid by means, of steam
or hot-air pipes, instead of by injection of steam, as hitherto. The bottoms of the
stills or of the other vessels in which the peroxidation takes place when when
it is effected by injection of air and.is not performed in the stills themselves
instead of being. flat may, be more or less conical, paraboloidal, or egg-shaped.
The process of peroxidation, whether by the wet or by the.dry, way, may be
performed either completely in the cold or partly in the cold and partly under
the influence of heat, or completely under the influence of heat; and, also
either wholly by means of ordinary air, or wholly by means of ozonized air, or
partly by means, of the one and partly by means of the other. When the
entire process is performed in the stills I prefer to make these vessels very,
large, and when of too large size to be constructed on the plan hitherto in
use. I make them externally of either iron or of brick work or other form of
masonry, and line them internally with either stone or any artificial material
capable of suitably resisting the action of hydrochloric acid and free chlorine.
When manufacturing chlorine by means of an artificial oxide of manganese
regenerated from still liquor I prefer in order to economise hydrochloric acid
to digest the oxide with less than a full equivalent of acid. This plan secures
that the still liquor produced contains no appreciable amount of free acid,
while the oxide left undissolved occasions no loss of manganese, inasmuch as
it accompanies the quantity of oxide next produced. When performing the

page_text: entire process in the stills the air required to peroxidise the protoxide may be
injected by means of moveable pipes let down through the man-holes after
the still liquor has been decomposed, and hoisted out again before more acid
goes in.
The artificial oxide of manganese produced as above described, or as described
in the Specifications of my former Patents above referred to, when not at
<first rich enough for use in the manufacture of glass, or in that of manganates
or permanganates, or for any other purposes for which a very rich peroxide
be required can be treated with dilute acid so as to dissolve out protoxide
until a peroxide of nearly one hundred per cent. remains behind.
SPECIFICATION in pursuance of the conditions of the Letters Patent, filed
by the said Walter Weldon in the Great Seal Patent Office on the
3rd March 1868.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, WALTER
WELDON, of Park Villa, West Hill, Highgate, in the County of Middlesex,
send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her Letters
Patent, bearing date the Fourth day of September, in the year of our Lord
One thousand eight hundred and sixty-seven, in the thirty-first year of Her
reign, did, for Herself, Her heirs and successors, give and grant unto me,
the said Walter Weldon, Her special licence that I, the said Walter Weldon,
my executors, administrators, and, assigns, or such others as I, the said Walter
Weldon; 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 Great Britain and Ireland, the Channel
Islands, and Isle of Man, an Invention for "IMPROVEMENTS IN THE PRODUCTION
OF ARTIFICIAL OXIDES OF MANGANESE, AND IN THE MANUFACTURE OF CHLORINE BY
MEANS THEREOF, PARTLY APPLICABLE ALSO TO OTHER PURPOSES," upon the condition
(amongst others) that I, the said Walter Weldon, my executors or adminis
trators, by an instrument in writing under my, or their, or one of their
bands 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 he filed in the Great Seal Patent Office within six
calendar months next and immediately after the date of the said Letter:
Patent.

page_text: NOW KNOW YE, that 1, the said Walter Weldon, do hereby declare the
nature of my said Invention, and in what manner the same is to be per-
formed, to be particularly described and ascertained in and by the following
statemen (that is to say):-)
I. This Invention consists, firstly, in the use of ozonized air in any method
of peroxidizing oxides of manganese which have been recovered from residual
products of the manufacture of chlorine, whether such peroxidation be
effected in the wet way or in the dry way, and whatever the agent by
whose means the said oxides may have been recovered. By ozonized air
I intend to be understood air the oxygen of which whether by the air
having been submitted to suitable electrical action or by any other available
means has been rendered more than normally active, and therefore practically
at least for the purposes of the present Invention, more or less in the con-
dition of what is known as " ozone."
II. This Inventon consists, secondly, in certain methods of applying atmo-
spheric air, whether oxonized or not, to a mixture of low artificial oxide of
manganese with water or other suitable liquid in order to the peroxidation of
the low oxide contained therein; which methods of applying air to such
mixture, though I do not consider them to be so generally advantageous as
the method which I have described in the Specification of a former Invention,
the Letters Patent for which are numbered 1948, and bear date the 26th of
July 1866, may yet be conveniently available in certain cases. The said
methods consist, firstly, in pumping, forcing, or otherwise lifting or elevating
a mixture of low artificial oxide of manganese with a suitable liquid from one
level to a higher one, and then allowing. it to fall through an atmosphere or
current of air, ozonized or not, from the said higher level to any other con-
venient level below it, proceeding in this way repeatedly, if necessary, until the
low oxide has been sufficiently peroxidized; secondly, in placing the mixture
of oxide and liquid in any convenient "churn" and mechanically "churning"
it in contact with air until the desired end has been accomplished; thirdly,
in placing the said mixture in an open vessel of more or less considerable
depth at or near the centre, but having sloping sides of large extent of surface,
and then by means of any suitable paddle wheel or other mechanical appliance
duly adapted to the deeper part of the vessel agitating the mixture more or
less violently, dashing it about so as to bring all parts of it successively to the
surface, and so as to constantly fling portions of it on to the sides of the vessel,
by running down which to the deeper part of the vessel, its exposure to the
air is advantageously prolonged; and, fourthly, in combining any two or more
of these methods.

page_text: III. This Invention consists, thirdly, in certain methods of proceeding in
order to effect the peroxidation of low oxides of manganese in the dry way at
ordinary temperatures. It is enough, when a sufficiently long time can be
allowed for the peroxidation, to spread the oxide thinly over a large surface
and simply so leave it in contact with air, ozonized or not, until its peroxida-
tion shall have been sufficiently accomplished; but I prefer in all such cases
to facilitate the peroxidation by crushing the oxide when requisite, and so
keeping it as much as possible in the state of powder, and by then stirring
into it and turning it over from time to time either by manual labour or by
the aid of suitable mechanical appliances. The oxide to be thus peroxidized
when
at ordinary temperaturés may be spread over a field or other open space
its peroxidation is effected by ordinary air; but when employing ozonized air
the oxide must of course be exposed under cover. A good plan is to place
the oxide in a slowly revolving cylinder, and to blow air through this cylinder
if ozonized air be employed; or to either blow or draw it through if ordinary
air be used. Another good plan is to place the oxide in thin layers on trays
arranged one above another or otherwise in a room through which air is either
blown or drawn by a blast engine, or by a fan, or by connexion with a
chimney or other suitable means. Still another plan is to place the oxide on
the floors of shallow flues, through which a draught or current of air is kept
passing as before. These flues may be constructed of either brick, or stone,
or iron, or other suitable material, and in sets one above another, and from
end to end of each, first in one direction and then in the contrary, either a
simple strip of metal stretching from side to side of the flue and arranged at
a suitable angle, or a roller furnished with one or more such knife-like strips
of metal may be kept slowly travelling so as constantly to turn over the oxide
and thereby hasten its peroxidation. A further method of operating in the
dry way at ordinary temperatures consists in exposing the oxide, either under
cover or in any open space, in heaps, rendered as porous as possible by admixture
with sand, pebbles, or fragments of stone, brick, slag, or any other material
which will serve to divide the mass while admitting of being readily separated
from the peroxidized oxide, or not being hurtful if allowed to remain with
it. A similar admixture can also be used when the oxide is exposed otherwise
than in heaps. The oxide can also be made up iuto heaps or masses divided
by earthenware or other tubes, which should preferably be of as porous a nature
as possible, and be provided with more or less numerous small perforations.
IV. This Invention consists, fourthly, in peroxidizing low oxides of man-
ganese in the dry way at higher than ordinary temperatures by passing over
the oxide which is to be peroxidized a current of heated air only, or otherwise

page_text: exposing it under the influence of heat to the action of air alone, or of air
mixed with vapour of water, instead of exposing it to a mixture of heated air.
and heated products of combustion, which is what has been done hitherto
whenever it has been attempted to peroxidize low oxides of manganese in the.
dry way. The peroxidation by this method of low oxides of manganese can
be effected in any convenient vessel or oven, but perhaps the best plan is to
place the oxide in a revolving cylinder, and to pass through that, the requisite
heated air or mixture of heated air and vapour of water. It will be obvious
that certain others of the arrangements described in the paragraph last pre-
ceding this will be equally available also when working at higher than ordinary
temperatures; and, moreover, that the use of a revolving cylinder through.
which heated. air is passed is applicable not only to the production, of a more
or less rich peroxide from protoxide or other low oxide of manganese, but like-
wise to the production of peroxide from carbonate of manganese.
V. This Invention consists, fifthly, in certain details of proceedure and.
apparatus which it will sometimes. be useful to adopt when performing in the,
wet way the peroxidation of oxide of manganese recovered from chlorine
residues. These said. details consist, firstly, in using the lime employed (when,
lime is the agent by. means of which the chloride of manganese, in the chlorine,
residues is. decomposed) in as fine a state of division as possible, and as free as
possible from impurities, in order to which end I grind it in any suitable mill,
preferably with water, and so arrange that all lumps and, heavy impurities may,
be separated from the resulting fine milk of lime by subsidence; secondly, in
dispensing. with false bottoms to the stills when performing the recovery of
the oxide of manganese and its subsequent peroxidation in the chlorine stills
themselves; thirdly, in filling up the corners of the stills at the bottom, so as
to make each still at the bottom more or less egg-shaped or paraboloidal, or
more or less of the shape of an inverted truncated cone; fourthly, in drying
the peroxidized oxide more or less completely in the stills themselves by
means of an injected blast of heated air; fifthly, in economising hydrochloric
acid when manufacturing chlorine by means of artificial oxides of manganese
continually recovered from the residue of that manufacture by digesting the
oxide each time with a quantity of acid not quite sufficient to dissolve the
whole of it, whereby a still liquor is obtained in which there is little or no free
acid, while the oxide left undissolved involves no loss of manganese, inas-
much as it is simply added to the quantity of manganese next produced;
sixthly, in obtaining a rich peroxide of manganese from a less rich peroxide
produced in the wet way by dissolving protoxide out therefrom by means of
weak acid; seventhly, in making the stills in which chlorine is generated by

page_text: means of oxide of manganese, and in which oxide of manganese is afterwards
recovered for use over again, externally either of iron or of brickwork or other
form of masonry, and lining them internally with either stone or ebonite, or
any other convenient substance not readily acted upon by either hydrochloric
acid or free chlorine; and, eighthly, in performing the peroxidation of low
oxides of manganese, whether in the wet way or in the dry way, partly in the
cold and partly under the influence of heat, and also partly by means of
ordinary air, and partly by means of ozonized air.
VI. This Invention consists, sixthly, in employing artificial oxides of
manganese peroxidized and otherwise treated as above described in the manu-
facture of chlorine, glass, and manganates and permanganates, as a source of
free oxygen, and for whatever other purposes native oxides of manganese are
available.
Having thus declared the nature of my Invention, and the manner in which
the same is to be performed, I wish it to be understood that what I claim as
new and original and desire to be secured to me by the herein in part recited
Letters Patent are, the use of ozonized air for the peroxidation of low oxides
of manganese, whether in the wet way or in the dry way; the various methods
of proceedure, whether using ozonized air or ordinary air, and likewise the
various details of apparatus, etc. which are all duly set forth above, and the
use for the purposes indicated of artificial oxides of manganese peroxidized and
otherwise produced and treated as described.
In witness whereof, I, the said Walter Weldon, have hereunto set my
hand and seal, this Second day of March, in the year of our Lord
One thousand eight hundred and sixty-eight.
WALTER WELDON. (L.S.)