Improvements in Volatilizing Ammonium Chloride and in Obtaining Ammonia, Chlorine, and Hydrochloric Acid therefrom, also in Obtaining Chlorine from Hydrochloric Acid.
Year: 1889

page_text: Date of Application, 13th Feb., 1889
• Complete Specification Left, 13th Nov., 1889-Accepted, 21st Dec., 1889
PROVISIONAL SPECIFICATION.
Improvements in Volatilizing Ammonium Chloride and in Obtaining
Ammonia, Chlorine, and Hydrochloric Acid therefrom, also in
Obtaining Chlorine from Hydrochloric Acid.
1, LUDWIG MOND of Winnington Hall, Northwich, Cheshire, Manufacturing chemist,
do hereby declare the nature of this invention to be as follows:-
In previous patents numbered and dated 65, 66, 1048, 1049, and 3238 of 1886 and
10955 of 1887 respectively I have described new processes for obtaining ammonia and
chlorine from ammonium chloride, and have proposed various ways of carrying these
processes into practice..
These processes are all based on the following chemical reactions; the action of
ammonium chloride, by preference previously vaporized, upon certain oxides or salts
at a suitable temperature, which gives rise to the formation of fixed, chlorides or oxy-
chlorides and liberates ammonia; and subsequently the action of air or steam upon
the fixed chlorides or oxychlorides so obtained at a more elevated temperature, than
the one employed during the previous operation by which chlorine or hydrochloric
acid is obtained and the oxide or salt originally employed is regenerated.
In several of the patents named above I have already pointed out the great and
peculiar difficulties which I have met with in trying to carry these apparently simple
processes into practice and more particularly the difficulties I have encountereil in
constructing durable apparatus for these processes which would at the same time allow
the various operations to be carried out within a reasonable time, and to regulate in an
efficient manner the different.temperatures at which the various operations have to be
carried out.
I have proposed numerous methods for overcoming these various difficulties, but
will now proceed to describe what I have found, after several years of experimenting,
the most practical and economical way for carrying theso processes out on a largo
scale. The ammonium chloride is vaporized, in a still or retort (heated on the outside)
which is set into a suitable furnace in such a way that only the lower part of the still
is exposed to the full beat of the furnace. This still is filled with zinc chloride or its
substitute to such an extent that when the chloride is melted it fills the still a little
higher than the portion exposed to the full heat of the furnace. I introduce the
ammonium chloride through a suitable hopper or feeder into this still in small
quantities or continuously, and allow it to drop on the molten zinc chloride and thus
obtain a very rapid vaporisation. Those parts of the still which are not exposed to
the full heat of the furnace must be kept at a temperature above 350. C., so that the
volatilized ammonium chloride is not condensed again.
1
I have met with considerable difficulties in constructing a still, for this purpose,
which would resist the action of molten zinc chloride and of the ammonium chloride
vapor. I had formerly proposed to use nickel or cobalt for this purpose, but have
found it impossible to get vessels of large dimensions made of these metals; they,also
do not resist sufficiently well the action of the ammonio-zinc-chloride formed when
ammonium chloride is dropped into zinc chloride. I therefore now propose to use
antimony in the construction of these stills, which substance, after many experiments,
I have found the only metal answering all the conditions required for my purpose, or
of alloys of antimony in which this metal so largely predominates that they will resist
the corrosive action of the substances named, sufficiently for practical purposes. In
order to make a strong and durable apparatus and to save antimony I prefer to make
the still of cast-iron, and to line it on the inside with antimony or an alloy of
antimony.

page_text: The vapor of ammonium chloride produced in this still 1 take through conduits, by
preference constructed of cast-iron lined with antimony or with earthenware tiles, and
which are also kept heated above 350 C., into vertical cylinders which contain the
oxide or salt to be acted upon. Of the numerous substances that can be used for the
process I prefer a mixture of magnesia with a certain quantity of chloride of potassium.
I have found it convenient to add to these substances a certain quantity of china clay
and also a little lime or chloride of calcium. The magnesia used should not be too
dense. I find the product obtained by precipitation with milk of lime from natural
brine or sea-water or other salt, containing chloride of magnesium, subsequent
settling and washing, preferably by means of filter presses, and then exposing to a
moderate heat to expel the water of hydration, very suitable. for my purpose. I have
obtained good results by adding to, every, 100 parts, of magnesia 75 parts of china clay
and 6 parts of quicklime.
I mix these substances thoroughly and then grind them in a suitable mill, with the
addition of a solution of chloride of potassium of 17 to 20° Twaddle, in sufficient
quantity to obtain a thick paste. Of this paste I make small round balls or pills of
about inch diameter, by means of suitable machinery. These pills are dried care-
fully and then heated to a low red heat. For the drying I prefer to use a travelling
band passing through a, heated chamber, and for the subsequent heating a vertical iron
retort working continuously.
In this way very hard pills are obtained, which will stand the repeated chloridizing
and oxidizing for a long time. These pills are filled into the, cylinders named above
to a convenient height, say 6 to 8 feet, and rest, on a false bottom, or on a layer of
broken, bricks or of pills of the same material but of larger size than the rest, of the
pills..
Theso cylinders, which are closed at top and bottom, I construct of bricks or tiles
of good fire-clay set in a suitable cement, say a mixture of sulphate of baryta and
silicate of soda. I make the walls of these cylinders of considerable thickness, and
prefer to build them of several rings or layers, between which I put bad conductors of
heat, such as anhydrous magnesia, in order to prevent loss of heat by radiation as
much as possible.
I prefer to enclose these cylinders in a casing of cast or wrought iron so as to mako
them perfectly gas tight, and to set them into a furnace, so that the outside of the
cylin lers can be heated, in case this should be found necessary.
The. cylinders are provided with inlets on the top, which can be opened and
closed, at will by suitable plugs or valves, which may bo made of nickel or
earthenware. One of these inlets is connected with the ammonium chloride still,
and serves for the entrance of the ammonium chloride vapor. Others serve for the
introduction of hot or cold inert gases, hot or cold air, or superheated steam, as the
case may be. Near the bottom, the cylinder is provided with one or several' outlets
to take away the various gases passing through or formed' in the cylinders.
Previous to introducing any ammonium chloride vapor into these cylinders I pass a
current of, hot inert gas through them so as to raise the temperature of the pills inside
the cylinders to about. 350 C When this temperature has been reached the hot, gas
is shut off and chloride. of ammonium vapor passed in in such quantity and' at such a
speed as the quantity of pills will allow. The ammonia formed is taken from the
bottom of the cylinder to a convenient absorbing apparatus., When sufficient
ammonium chloride has been passed' through, the valves or plugs admitting it are shut
off and a current of inert gas, previously heated' to, a temperature of 500 to 550°C.
is now passed through the cylinders. For a certain time this gas on leaving the
bottom of the cylinders, carries with it a certain quantity of ammonia, and is passed
through a suitable washing apparatus for absorbing this ammonia. When the
ammonia, ceases the gas carries with it a certain quantity of hydrochloric acid.. As
soon, as this appears. the gas is turned through a different set of conduits into a suitable.
apparatus for absorbir this hydrochloric acid. When all the hydrochloric acid is
driven out of the cylinders the pills have generally arrived at a temperature of 500

page_text: to 550 C. If not the current of hot inert gas is continued until this temperature is
reached. The inert gas used for this purpose must be as far as possible free from
oxygen and vapor of water, in order that it shall not itself act upon the chloride of
magnesium in the pills. The gases obtained from a well conducted lime-kiln and the
gasos escaping from the absorbing columns used in the ammonia soda process are if
the necessary precautions are taken to keep these gases as free as possible from oxygen,
quite suitable for this purpose, more particularly after carefully drying them by means
of strong sulphuric acid.
When the pills have arrived at the temperature above named (500 to 550 C) the
current of inert gas is stopped and a current of hot air introduced. The air is pre-
viously carefully dried by contact with strong sulphuric acid, and then heated to a
temperature of 800° to 1000° C. by preference by means of a Cowper stove.
Air at
this temperature decomposes the chloride of magnesium very readily and quickly, and
on leaving the bottom of the cylinders it contains from 7 to 10 per cent. of chlorine,
which is practically free from hydrochloric acid if the previous operation has been
carefully conducted, and can, after cooling in cast iron pipes be directly introduced
into suitable apparatus such as a Deacon Bleaching Powder Chamber for the absorption
of dilute chlorine gas by lime.
Towards the end of the operation the gas becomes weak in clilorine. I then pass
this gas through a Cowper stove to heat it up again to '800° to 1000° (, and
take it through another cylinder ready for the production of chlorine; in this way
I keep the chlorine gas which goes to the bleaching powder chamber at a reasonable
strength.
When the chlorine has been driven out as far as is'ilesirable I pass cold air through
the cylinders in order to reduce the temperature of the pills again to about 400° C.
This cold air gets heated in its passage through the hot pills, and is also passed
from the bottom of the cylinders to a Cowper stove or other heating apparatus
to be heated up further and then to be used for liberating chlorine in another
cylinder. In place of cold air I may use cold inert gases and employ these sub-
sequently for heating up the pills in another cylinder. When the temperature of
the pills has been sufficiently reduced the cold air or inert gas is shut off the
ammonium chloride vapor again admitted and the cycle of operations repeated
as before described.
If it is desired to produce hydrochloric acid instead of chlorine, I use in place of
hot air superheated steam, and take the gases issuing from the cylinters to a suitable
apparatus for condensing the hydrochloric acid formed.
In a Patent numbered and dated 8308 of the 23rd June 1886 I have described a
process for obtaining chlorine from hydrochloric acid gas in a very similar way to
that proposed for obtaining it from ammonium chloride. I have found that this process
can be carried out on a large scale very advantageously in the same manner as herein-
before described by substituting gases containing hydrochloric acid, such as are obtained
in various chemical operations, for the vapor of ammonium chloride.
Dated this 18th day of February 1889.
W. P. THOMPSON & BOULT,
A genis.
COMPLETE SPECIFICATION.
Improvements in Volatilizing Ammonium Chloride and in Obtaining
Ammonia, Chlorine, and Hydrochloric Acid therefrom, also in
Obtaining Chlorine from Hydrochloric Acid.
I, LUDWIG MOND of Winnington Hall, Northwich, in the County of Chester,
Manufacturing Chemist, 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 :—
In previous patents numbered and dated 65, 66, 1048, 1049 and 3238 of 1866 and

page_text: 10955 of 1887 respectively, I have described new processes for obtaining: ammonia
and chlorine from ammonium chloride and have. proposed various ways of carrying
these processes into practice, also in my provisional application No. 2160 of 1889, I
have described the apparatus used in vaporising the ammonium chloride.
These processes are all based on the following chemical reactions; the action of
ammonium chloride, by preference previously vaporised, upon certain oxides or salts
at a suitable temperature, which gives rise to the formation of fixed chlorides or oxy-
chlorides and liberates ammonia, and subsequently the action of air or steam upon the
fixed chlorides or oxy-chlorides so obtained at a more elevated temperature than the
one employed during the previous operation by which chlorine or hydrochloric acid is
obtained and the oxide or salt originally employed is regenerated.
In several of the patents named above, I have already pointed out the great and
peculiar difficulties which I have met with in trying to carry these, apparently
simple processes into practice, and more particularly the difficulties I have encountered.
in constructing durable, apparatus for these processes which would at the same
time allow the various operations to be carried out within a reasonable time, and
to regulate in an efficient manner the different temperatures at which the various
operations have to be carried out.
I have proposed numerous methods for overcoming these various difficulties, but
will now proceed to describe what I have found, after several years of experimenting,
the most practical and economical way for carrying these processes out on a large
scale. The ammonium chloride is vaporised in a still or retort (heated on the outside)
which is set into a suitable furnace in such a way that only the lower part of the
still is exposed to the full heat of the furnace. This still is filled with zinc chlorido or
its substitute to such an extent that when the chloride is melted it fills the still
I intro-
a little higher than the portion exposed to the full heat of the furnace.
duce the ammonium chloride through a suitable hopper or feeder into this still in
small quantities or continuously, and allow it to drop on the molten zinc chloride and
thus obtain a very rapid vaporisation. Those parts of the still which are not exposed
to the full heat of the furnace must be kept at a temperature above 350 degrees
Centigrade, so that the volatilised ammonium chloride is not condensed again.
I have met with considerable difficulties in constructing a still for this purpose,
which would resist the action of molten zinc chloride and of the ammonium chloride
vapour. I had formerly proposed to use nickel or cobalt for this purpose, but have
found it impossible to get vessels of large dimensions made of these metals; they also
do not resist sufficiently well the action of the ammonio-zine-chloride formed when
ammonium chloride is dropped into zinc chloride.
Moreover, if ammonium chloride be vaporised in vessels made of iron, copper,
brass or almost any other metal industrially applicable, the ammonium chloride vapour
produced is contaminated with the vapour of the chloride of the metals of which the
apparatus has been made. I have, however, found that ammonium chloride vapour
quite free from metallic chlorides can be obtained by volatilising the ammonium
chloride in vessels made of or lined with antimony, which substance, after many
experiments, I have so far found the only metal answering the conditions required for
my purpose. I therefore now propose to use vessels made of or lined with antimony
or alloys of antimony in which this metal so largely predominates that they will
resist the corrosive action of the substances named, sufficiently for practical purposes.
In order to make a strong and durable apparatus and to save antimony, I prefer to
make the still of cast iron, and to line it on the inside with antimony or an alloy of
antimony.
The vapour of ammonium chloride produced in this still, I take through conduits,
by preference constructed of cast iron lined with antimony or with earthenware tiles,
and which are also kept heated above 350 degrees Centigrade, into vertical cylinders
which contain the oxide or salt to be acted upon. Of the numerous substances that
can be used for the process, I prefer a mixture of magnesia with a certain quantity of
chloride of potassium, I have found it convenient to add to these substances a certain

page_text: i
quantity of china clay and also a little lime or chloride of calcium. The magnesia.
used should not be too dense. I find the product obtained by precipitation with milk...
of lime from natural brine or sea water or other salt containing chloride of magnesium,
subsequent, settling and washing, preferably by means of filter presses, and then
exposing, to moderate heat to expel the water, of hydration, very suitable for my:
purpose. I have, obtained good results by adding to every, 100 parts of magnesia.
75 parts of china, clay and 6 parts of quick lime.
I mix these substances, thoroughly and, then grind-them in a suitable mill, with
the addition of a solution of chloride of potassium of. 17 to 20 degrees Twaddle, in,
sufficient quantity to obtain a thick.paste. Of this, paste I make small round balls or,
pills of about half an inch diameter, by means, of suitable machinery. These, pills are..
dried carefully and then heated to a low red heat. For the drying, I prefer to use a
travelling band passing through a heated chamber and for the subsequent heating a
vertical iron retort working continuously.
•
11
In this way very hard pills are obtained, which will stand, the repeated chloridising...
and oxidising for a long time. These pills are filled into these cylinders named above...
to a convenient height, say 6 to 8 feet, andi-rest, in, a false bottom or on a layer of
broken bricks or of pills of the same material, but of larger size than the rest of the
pills.
|
"
:
These cylinders, which are closed at top and bottom, I construct of bricks or tiles.,
of good fire clay, set in suitable cement, say a mixture of sulphate of baryta, with
sufficient strong solution of silicate of soda,to, make, a plastic mass. I make the walls,...
of these cylinders of considerable thickness, and profer to build them. of several rings
or layers; between which I put bad, conductors, of heat, such as anhydrous magnesia,
in order to prevent loss of heat by radiation as much as possible.
y
I prefer to enclose these cylinders in a casing of cast or wrought iron so as to make
them perfectly gas tight, and to set them into a furnace, so that the outside of tho n
cylinders can be heated, in case this should be found, necessary.
T
"
The cylinders are provided with inlets on the top, which can be opened and, closed.
at will by suitable plugs or valves, which may be made of nickel or earthenware.,.,One
of these, inlets is connected, with, the ammonium chloride still, and serves for the
entrance of the ammonium chloride vapour... Others serve for the introduction of hot..
or cold inert gases, hot or cold air or superheated, steam, as the case may be. in Near.
the bottom, the cylinder is, provided with one or several outlets to take away. the t.
various gases passing through or formed in the cylinders.
:
Previous to introducing any ammonium chloride vapour, into, these cylinders, I pass.
a current of hot inert gas through them, so as to raise the temperature of the pills,
inside the cylinders to about 350 degrees. Centigrade. When this, temperature has,
been reached, the hot gas is shut off, and chloride of ammonium vapour passed in, in
such quantity and at such a speed as the quantity of, pills will, allow.., The,ammonia
formed is taken from the bottom of the cylinder to a convenient absorbing apparatus...
When sufficient ammonium chloride has been passed through, the valves or plugs
admitting it are shut off and a current of inert gas previously heated to a temperature ..
of 500 degrees to 50 degrees, Centigrade is now, passed through the cylinders... For..
a certain time, this gas on, leaving the bottom of the cylinders carries with it a certain...
quantity of ammonia, and is passed through a suitable washing apparatus for absorbing,
this ammonia. When the ammonia ceases, the gas carries with it.a, certain quantity
of hydrochloric acid. As soon as this appears the gas is turned through, a different
set of conduits into a suitable apparatus for absorbing, this hydrochloric acid... When
all the hydrochloric acid is driven out of the cylinders, the pills have, generally arrived
at a temperature of 500 degrees to 550 degrees Centigrade.. If not, the current of hot ..
inert gas is continued until this temperature is reached. The inert gas used for this
purpose must be as far as possible free from oxygen and vapour of water, in order, that
it shall not itself act upon the chloride of magnesium in the pills.The gases obtained.,
from a well conducted lime-kiln and the gases escaping from the absorbing columns...
used in the ammonia soda process are, if the necessary precautions are taken to keep
t

page_text: these gases as free as possible from oxygen, quite suitable for this purpose, more
particularly after carefully drying them by means of strong sulphuric acid.
When the pills have arrived at the temperature above named (500 degrees to
550 degrees Centigrade) 'the current of inert gas is stopped and a current of 'hot
air introduced. The air is previously carefully dried by contact with strong sulphuric.
acid and then heated to a temperature of 800 degrees to 1000 degrees Centigrade
by preference by means of a Cowper stove. Air at this temperature decomposes
the chloride, of magnesium very readily and quickly, and on leaving the bottom of the
cylinders it contains from 7 to 10 per cent. of chlorine, which is practically free
from hydrochloric acid, if the previous operation has been carefully conducted, and
can, after cooling in cast iron pipes be directly introduced into suitable apparatus
such as a Deacon Bleaching Powder Chamber for the absorption of dilute chlorine
gas by lime.
Towards, the end of the operation, the gas becomes weak in chlorine. I thon
pass this gas through a Cowper stove or other suitable heating apparatus to heat it
up again to 800 degrees to 1000 degrees Centigrade, and take it through another
cylinder ready for the production of chlorine; in this way I keep the chlorine gas
which goes to the bleaching powder chamber at a reasonable strength.
When the chlorine has been driven out as far as is desirable, I pass cold air through
the cylinders in order to reduce the temperature of the pills again to about 400 degrees
Centigrade. This cold air gets heated in its passage through the hot pills, and is also
passed, from the cylinders to a Cowper stove or other heating apparatus to be heated
up further and then to be used for liberating chlorine in another cylinder. In place
of cold air, I may use cold inert gases and employ these subsequently for heating up
the pills in another cylinder. When the temperature of the pills has been sufficiently
reduced, the cold air or inert gas is shut off, the ammonium chloride vapour again
admitted and the cycle of operations repeated as before described.
In order to more fully explain the carrying out of the process, I have appended
horeto two Figures of drawings, in 'these,
Figure 1 is a section of the entire apparatus.
Figure 2 section through line YZ, Figure 1, transversely to Figure 1 of the
converting apparatus. In these, A is the retort for evaporating ammonium chloride,
this is filled to point a with fused chloride of zinc and is lined with antimony as
shown in hatchings a¹. Bis the hopper for supplying solid ammonium chloride,
regulated by valve b, C discharging orifice, D central support, d side supports, both of
refractory material such as fire clay. E air entrance to reduce temperature, F flues,
fexit for flue gases, G passage to converter,
valve for shutting or regulating said
passage, g similar valve. If this valve is at its highest point, the passage is open; if
closed, but valve g open, the chamber A is open to the air; if, in a similar way g is
closed down and g¹ drawn up, chamber H hereafter described is open to the atmo-
sphere. His the converting chamber receiving the ammonium chloride vapour by
passage G, I opening for charging the pills, shown in dots, into vessel H, J'exit of
chlorine gases, P exit of ammoniacal gases, K entrance for air or inert gas as
required; being connected to the supply of both by pipes not shown in drawing, pipe
for supplying producer gas in case the apparatus is worked in this way. M similar
pipe for supplying air, NN manholes.
The mode of action is as follows :-
The molten zinc chloride and pills being placed in their respective vessels and the
requisite degree of temperature attained, ammonium chloride is introduced into A and
falling into the molten zinc chloride is speedily volatilised and its place from time to
time supplied with further ammonium chloride till the pills are sufficiently chloridised.
The ammonium chloride being vaporised in an antimony vessel arrives at the pill
chamber pure instead of being contaminated, as it would be if evaporated in any other
vessel known to me, by the materials of the retort; when the pills are sufficiently
chloridised, the vaporisation of ammonium chloride is stopped by the supply of

page_text: ammonium chloride being cut off or the vapour is: diverted to another chamber: H.
Valve g is closed and the remaining part of the process carried out; in chamber H.,
If it is desired to produce hydrochloric acid instead of chlorine, I use in place of hot
air, superheated steam, and take. the gases issuing from the cylinders: to, a suitable
apparatus for condensing the hydrochloric acid, formed.
In a patent numbered and dated 8308 of the 23rd June 1886, I have described a
process for obtaining chlorine from hydrochloric acid gas in a very similar way to that
proposed for obtaining it from ammonium chloride: I have found that this process
can be carried out on a large scale very advantageously in the same manner as herein-
before described by substituting gases. containing hydrochloric. acil, such as are
obtained in various chemical operations for the vapour of ammonium chloride.
Having now particularly described and ascertained the nature of my said inven-
tion and in what manner the same is to be performed, I wish it to be understood
that I make no claim under this application for a patent for anything by itself set
forth or claimed in any of my previous patents as enumerated at the commencement
of this specification nor for the apparatus described and claimed in my aforesaid pro-
visional specification No. 2160 of 1889 and in the complete specification in pursuance
of the same application which is filed contemporaneously with this complete specification,
but I declare that what 1 claim is :-
1. The process of obtaining chlorine, which consists in heating to about 350 degrees
Centigrade, pills or fragments of oxide or salt such as described, capable of decom-
posing the ammonium chloride or hydrochloric acid used, and of absorbing chlorine in
place of oxygen, than either vaporizing ammonium chloride in molten zinc chloride,
protected from contamination with foreign matter by antimony or forming hot
hydrochloric acid gas, passing the ammonium chloride vapour or hot hydrochloric acid
gas through said pills or fragments, till the power of said pills or fragments to take up
chlorine is sufficiently spent, collecting the ammonia given off (when ammonium chloride
is operated upon) then raising and regulating the heat of the pills by passing through
them hot inert gas and saving what ammonia and afterwards hydrochloric acid are given
off, then passing dry hot air through and thus liberating the chlorine previously
absorbed; utilising the chlorine so obtained by passing it into bleaching powder
chambers or otherwise, and when the gases become too weak for this process utilising
them in liberating chlorine from a fresh batch of pills. Then again lowering the
temperature of the pills by passing through cold air or cold inert gas and when the
requisite temperature has arrived, recommencing the cycle of operations by passing
the ammonium chloride vapour or hot hydrochloric acid gas through, substantially as
described.
2. The improvement in the process of obtaining chlorine by means of repeated
chloridation and oxidation of certain oxides or salts by their alternate exposure when
heated to the vapour of ammonium chloride or hydrochloric acid gas and to air,
regulating the different temperatures required by the two operations by passing
through the material to be treated a current of inert gas of suitable temperature, or in
the case of the oxidized salts a current of cool air between the operations, substantially
as described.
3. The improvement in the process of obtaining chlorine by means of repeated
chloridation and oxidation of certain oxides or salts by their alternate exposure, when
heated, to the vapour of ammonium chloride or of hydrochloric acid and to air, heating
to about 900 degrees Centigrade the air which is only weakly charged with chlorine
(near the end of the process) and passing it through another batch of chloridised salts,
whereby the very diluted chlorine otherwise useless is saved and goes to enrich a
subsequent process.
4. The improvement in the process of obtaining chlorine from ammonium chloride
which consists in vaporizing the ammonium chloride in vessels formed of or lined with
antimony sufficiently unalloyed with other metals as to withstand the corrosive action
of the charge, whereby a vapour of ammonium chloride is obtained free from the

page_text: .Fcontamination of other chlorides which would otherwise be formed by the corrosivo
action of the charge upon the material of the vessel.
to 5. The use in the manufacture of chlorine of the apparatus substantially as herein
described and claimed but subject to the above disclaiming clause.
Dated this 12th day of November 1889.
:
WM. P. THOMPSON & Co.,
Of 6, Lord Street, Liverpool, Patent Agents for the Applicant.