AN IMPROVED METHOD OF AND APPARATUS FOR DECOMPOSING CHLORIDE OF SODIUM AND CHLORIDE OF POTASSIUM FOR THE PRODUCTION OF COMPOUNDS OF SODA AND POTASSA."
Year: 1862

page_text: LETTERS PATENT to William Gossage, of Widnes, in the County of
Lancaster, Chemist, for the Invention of "AN IMPROVED METHOD
OF AND APPARATUS FOR DECOMPOSING CHLORIDE OF SODIUM AND CHLORIDE OF
POTASSIUM FOR THE PRODUCTION OF COMPOUNDS OF SODA AND POTASSA."
PROVISIONAL SPECIFICATION left by the said William Gossage at the
Office of the Commissioners of Patents, with his Petition, on the 18th
July 1862.
İ. WILLIAM GOSSAGE, of Widnes, in the County of Lancaster, Chemist, do
hereby declare the nature of the said Invention for "AN IMPROVED METHOD OF
AND APPARATUS FOR DECOMPOSING CHLORIDE OF SODIUM AND CHLORIDE OF POTASSIUM
FOR THE PRODUCTION OF COMPOUNDS OF SODA AND POTASSA," to be as follows:-
My Invention has for its object the decomposition of chloride of sodium, and
chloride of potassium by subjecting such chlorides when in the state of vapour
to the action of the vapour of water, such decomposition being assisted by
certain solid substances, (which for the purpose of this description I will call
"decomposing substances," as contra-distinguishing them from the vaporous
bodies present in the operation,) in order to obtain certain compounds of sodá
and of potassa. The substances which I employ as "decomposing substances,"
are those which either contain silica or alumina, or contain both silica and
alumina.
I will firstly describe the mode by which I effect my Invention. as
applied to the decomposition of chloride of sodium (common salt) when using
silica as the "decomposing substance." | provide an apparalus consisting of
a tower or chamber constructed of fire-bricks, and I nearly fill the same by

page_text: placing therein nodules of flint, such as occur in the chalk strata; I connect
the lower part of such tower or chamber with a chimney draft, and the upper
part with a flue, through which I conduct heated gases or flame produced by
the combustion of fuel; and I cause such products of combustion to percolate
through the interstices existing between such nodules, and to pass off by the
chimney draft. By these means the nodules of flint become heated to a very
high temperature, and such being the case I introduce vapour of water into
the upper part of such tower or chamber, which mingles with the gaseous
products of combustion passing through the same; and I also introduce
.chloride of sodium, which, becoming volatilized by the high temperature. its
vapour mingles with the vapour of water and gaseous products of combustion,
and thus produces a mixture of gases containing chloride of sodium and water
both in the state of vapour at a high temperature, and such mixture of gases
percolates through the interstices existing between the highly heated nodules
of flint, and thus, the vaporous mixture of chloride of sodium and water is
maintained in contact with the highly heated silica, and under such circum-
stances the decomposition of chloride of sodium is rapidly effected, producing
silicate of soda (which flows to the lower part of such tower or vessel, and
can. be withdrawn therefrom), also hydrochloric acid gas (which passes
from such tower or vessel together with the other gaseous matters passing
therefrom), which may be obtained as liquid hydrochloric acid by condensation
with water previously to the residual gases passing off to the chimney. I
find it useful to assist the combustion of fuel used for procuring heat,
also the passage of the gases through the tower or vessel containing heated
nodules of flint, by the use of fans or blowers or other well-known means
employed for such purpose. The silicate of soda thus obtained is suitable
to be used for the manufacture of glass and for other well-known purposes.
It can also be used for the production of hydrate of soda (caustic soda)
and carbonate of soda. For these last-named purposes I dissolve the silicate
of soda with water, and when I wish to obtain hydrate of soda I treat such
solution with caustic lime, and I thereby produce caustic soda in solution and
silicate of lime as a precipitate; the solution of caustic soda may be concen-
trated so as to yield solid caustic soda. To obtain carbonate of soda I treat
the solution of silicate of soda with carbonic acid gas, and I thereby produce
carbonate of soda in solution and silica as a precipitate. The solution of
carbonate of soda may be concentrated so as to yield soda crystals or dried
carbonate of soda.
When I employ my Invention for effecting the decomposition of chloride of
potassium I proceed in the manner I have herein-before described for

page_text: decomposing chloride of sodium, except that I introduce chloride of potassium
into the heated tower or chamber in place of chloride of sodium. I obtain as a
product silica of potassa, which is useful for various purposes, also hydro-
chloric acid gas. By dissolving such silicate of potassa with water, and treating
the solution with caustic lime, I obtain caustic potassa in solution; or by
treating such solution with carbonic acid gas I obtain carbonate of potassa in
solution. When 1 use alumina as the "decomposing substance" for effecting
the decomposition of chloride of sodium or chloride of potassium, I obtain
aluminate of soda or aluminate of potassa as a product, which aluminates are
useful for sundry purposes, and by treating such aluminates in solution in the
manner I have described for the treatment of silica of soda or of potassa, 1
obtain hydrate of soda or of potassa, or carbonate of soda or of potassa there-
from, as the case may be. When I use a material containing silica and
alumina as the "decomposing substance" for effecting the decomposition of
chloride of sodium or chloride of potassium, obtain a mixture of silicate and
aluminate of soda or of potassa, and by treating such mixed silicate and
aluminate with caustic lime or carbonic acid gas (as herein-before mentioned
when describing the corresponding treatment of silicate of soda or of polassa)
I obtain therefrom caustic soda or caustic potassa, or carbonate of soda or
carbonate of potassa, as the case may be.
C
I have mentioned nodules of flint as a material suitable to be used as the
decomposing substance" in effecting my Invention; this is well suited for
the purpose as it is nearly pure silica, and it is found naturally in the state of
nodules or lumps which provide for the existence of channels or interstices
between the lumps when these are placed in the tower or chamber before
mentioned. There are sundry other natural substances which are nearly pure
silica, and when these are obtainable at a low price they are suitable to be
used as "decomposing substances." There are sundry natural substances which
contain silica and alumina (such as clay slate) which can be obtained in the
form of lumps or nodules at a low cost, and are suitable to be used as "decom-
posing substances." Ordinary clay when formed into dry lumps may also
be used for such purpose. There are sundry other natural substances "such
as felspar and granite) which contain silica and alumina, and which also contain
some soda or potassa. These are obtainable in the form of lumps or
nodules at a low cost, and are well adapted to be used as "decomposing sub-
stances" for the purpose of my Invention; when so used, the soda or polassa
previously existing in such substances is obtained in the mixed silicate and
aluminate produced.
:

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent, filed
by the said William Gossage in the Great Seal Patent Office on the 17th
January 1863.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, WILLIAM
GOSSAGE, of Widnes, in the County of Lancaster, Chemist, send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her Letters
Patent, bearing date the Eighteenth day of July, in the year of our Lord One
thousand eight hundred and sixty-two, in the twenty-sixth year of Her reign,
did, for Herself, Her heirs and successors, give and grant unto me, the
said William Gossage, Her special license that I, the said William Gossage,
my executors, administrators, and assigns, or such others as I, the said
William Gossage, my exccutors, 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 "AN
IMPROVED METHOD OF AND APPARATUS FOR DECOMPOSING CHLORIDE OF SODIUM AND
CHLORIDE OF POTASSIUM FOR THE PRODUCTION OF COMPOUNDS OF SODA AND POTASSA,"
upon the condition (amongst others) that I, the said William Gossage, by
an instrument in writing under my hand and seal, 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 1, the said William Gossage, 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
statement, reference being had to the Drawings hereunto annexed, and to the
letters and figures marked thereon (that is to say):-
My Invention has for its object the decomposition of chloride of sodium and
chloride of potassium by subjecting such chlorides when in the state of vapour
at a high temperature to the action of the vapour of water, such decomposition
being assisted by certain solid substances, (which for the purpose of this
description I will call "decomposing substances," as contra-distinguishing them
from the vaporous bodies present in the operation,) in order to obtain certain
compounds of soda and of potassa. I effect such object of my Invention by
the employment of an apparatus by means of which the said "decomposing
substances" are presented to the action of the said "vaporous bodies" under
such conditions as provide for the access of the said "vaporous bodies," to-

page_text: gether with the producis of the combustion of fuel, to the surfaces of the said
"decomposing substances," also provide for the passage of such "vaporous
bodies," together with the products of the combustion of fuel, through inter-
stices existing between the masses or pieces of such "decomposing substances."
The substances which I employ as "decomposing substances" are those which
either contain silica or alumina, or contain both silica and alumina.
I will firstly describe the mode by which I effect my Invention as
applied to the decomposition of chloride of sodium (common salt) when using
silica as the "decomposing substance." I provide an apparatus consisting of
a tower or chamber constructed of fire-bricks or other suitable refractory sub-
stance, and I nearly fill the same by placing therein nodules of flint such as
occur in the chalk strata. I connect the lower part of such tower or chamber
with a draft and the upper part with a flue, through which I conduct heated
gases or flame produced by the combustion of fuel, and I cause such products
of combustion to percolate through the interstices existing between such
nodules, and to pass off by a flue. By these means the nodules of flint become
heated to a very high temperature, and such being the case I introduce vapour
of water into the upper part of such tower or chamber, which mingles with
the gascous products of combustion passing through the same, and I also
introduce chloride of sodium, which becoming volatilized by the high tem-
perature its vapour mingles with the vapour of water and gaseous products
of combustion, and thus produces a mixture of gases containing chloride of
sodium and water both in the state of vapour at a high temperature, and
such mixture of gases percolates through the interstices existing between the
highly heated nodules of flint, and thus the vaporous mixture of chloride of
sodium and water is maintained in contact with the highly heated silica, and
under such circumstances the decomposition of chloride of sodium is rapidly
effected, producing silicate of soda in a state of fusion (which flows to the
lower part of such tower or vessel, and can be withdrawn therefrom), also
hydrochloric acid gas (which passes from such tower or vessel. together with
the other gaseous matters passing therefrom), and which may be obtained as
liquid hydrochloric acid by condensation with water previously to the residual
gases passing off to the chimney. I find it useful to assist the combustion of
fuel used for procuring heat, also the passage of the gases through the lower
or vessel containing heated nodules of flint, by the use of fans or blowers or
other well-known means ordinarily employed for such purposes.
The Drawings hereunto annexed represent such an apparatus as I use for
effecting my Invention.
Fig. 1 is a plan view in section taken through the dotted line. marked a, b,

page_text: in Fig. 2, which is a vertical view in section of the same. In these Figures
the same letters of reference are used to indicate similar parts.
A, A, is a tower or chamber constructed of fire-bricks or other suitable
refractory material bound together and supported by plates or bars of iron
applied externally. At A the internal space of this tower or chamber is
contracted, as shewn in the Drawings, and at A** it is again enlarged as also
shewn in the Drawing. This tower or chamber is nearly filled with nodules of
flint, and in consequence of the construction, as shewn in the Drawings at A*
and A, a space B, B, is left round the column of flints contained in the tower
or chamber A, which space communicates with a flue C. At the lower part
of the tower or chamber A an aperture D is provided, through which nodules
of flint may be withdrawn; such aperture is closed with a door of fire-brick
when the apparatus is working. An aperture E is also provided for running
off fused silicate of soda, and a flue C, through which residual gases may pass
off. F is a furnace for the combustion of fuel (of which one or more may be
used in connection with each tower or chamber). 1 arrange this furnace in
such manner that such combustion may be effected with a deficient supply
of atmospherical air, and thereby gaseous fuel capable of undergoing further
combustion by means of atmospheric air may be produced. G, G, are fire-bars
placed in a sloping direction; H is a dead plate, also placed in a sloping
direction, and protected by fire-bricks; I is a channel or hopper (closed by a
cover J) through which coal or coke may be introduced into the furnace F.
When coal is used this undergoes distillation on the dead plate H, and thus
furnishes combustible gas. The greater or less access of air to the fuel
undergoing imperfect combustion on the fire-bars G is regulated by the
thickness of such fuel, and the production of combustible gases from such
fuel is thereby regulated in the manner well understood. K is a vertical flue
through which the combustible gases proceeding from the furnace F are con-
ducted; L is a horizontal flue connecting the flue K with the tower or
chamber A; N is a pipe connected with a steam boiler, through which a
supply of steam can be conducted into the flue L; O is a pipe connected with
a centrifugal fan or blower P, through which a supply of air is conducted into
the flue L. The floor of the fluc L forms a platform on which chloride of
sodium (common salt) is supplied through openings Q. Q. R is an aperture
in the upper part of the tower or chamber A, through which nodules of flint
may be supplied as required.
The apparatus being constructed and arranged as herein-before described
I introduce burning fuel through the hopper I, so as to provide a thick fire on
the bars G, and I then introduce coal or coke, so as to produce a layer of

page_text: fuel on the bars G of about eighteen inches in thickness, and I close the
hopper I. I then cause a rapid current of air to be blown through the pipe O,
which assists mechanically the draft from the flue K, and mingling with the
gaseous fuel passing from such flue perfects the combustion of such fuel, and
produces an intense heat. The products of combustion, are caused to descend
through the tower or chamber A, and during such descent the nodules of flint
become intensely heated. These conditions being attained salt is introduced
from time to time on the floor of the flue I, and this becomes volatilized at the
same time steam is introduced through the pipe N, and this 'mingling with
the products of combustion and the vapour of salt becomes intensely heated,
and the mixed vapours percolate through the interstices between the nodules
of flint in the lower or chamber A, and are thus brought into intimate contact
with the highly heated silica, under which circumstances the chloride of
sodium becomes decomposed, yielding silicate of soda and hydrochloric acid
gas. The hydrochloric acid gas in mixture with other residual gases passes
off through the flue C and may be conducted (after previous cooling) into
the well-known apparatus used for the condensation of hydrochloric acid gas,
or these highly heated gases may be used for heating air and other gases
upon the system for which Letters Patent have been granted to Charles
William and Frederick Siemens, and such heated air and gases being applied
in effecting my Invention affords an important economy in fuel. I prefer to
assist the passage of gases through the condensing apparatus before referred
to, or through the apparatus of the said Charles William and Frederick
Siemens, by the use of centrifugal fans, or other well-known means employed
as exhausting apparatus, and connected with the final discharge flues of the
apparatus as arranged. Silicate of soda thus obtained is suitable to be used
for the manufacture of ordinary glass, and for other well-known purposes. It
can also be used for the production of hydrate of soda (caustic soda) and
carbonate of soda. For these last-named purposes I dissolve the 'silicate of
soda with water, and when I wish to obtain hydrate of soda I treat such solu-
tion with caustic lime, and I thereby produce caustic soda in solution, and
silicate of lime as a precipitate; the solution of caustic soda may be concentrated;
so as to yield solid caustic soda. To obtain carbonate of soda I treat the
solution of silicate of soda with carbonic acid gas, and I thereby produce car-
bonate of soda in solution, and silica as a precipitate. The solution of carbonate
of soda may be concentrated so as to yield soda crystals or dried carbonate
of soda.
When I employ my Invention for effecting the decomposition of chloride
of potassium I proceed in the manner I have hercin-before described for

page_text: decomposing chloride of sodium, except that I introduce chloride of potassium
into the heated tower or chamber in place of chloride of sodium. I obtain as
a product silicate of potassa, which is useful for various purposes, also hydro-
chloric acid gas. By dissolv.ng sul silicate of potassa with water, and
treating the solution with caustic lime, I obtain caustic potassa in solution;
or by treating such solution with carbonic acid gas I obtain carbonate of
potassa in solution. When I use alumina as the "decomposing substance"
for effecting the decomposition of chloride of sodium or chloride of potassium,
I obtain aluminate of soda or aluminate of potassa as a product, which alu-
minates are useful for sundry purposes, and by treating such aluminates in
solution in the manner I have described for the treatment of silicate of soda
or of potassa, I obtain hydrate of soda or of potassa, or carbonate of soda or
of potassa therefrom, as the case may be. When I use a material containing
silica and alumina as the "decomposing substance" for effecting the decom-
position of chloride of sodium or chloride of potassium, I obtain a mixture
of silicate and aluminate of soda or of potassa, and by treating such mixed
silicate and aluminate with caustic lime or carbonic acid gas (as herein-before
mentioned when describing the corresponding treatment of silicate of soda or
of potassa) I obtain therefrom caustic soda or caustic potassa, or carbonate
of soda or carbonate of potassa, as the case may be.
I have mentioned nodules of flint as a material suitable to be used as the
"decomposing substance" in effecting my Invention: this is well suited for the
purpose, as it is nearly pure silica, and it is found naturally in the state of
nodules or lumps which provide for the existence of channels or interstices
between the lumps when these are placed in the lower or chamber before
mentioned. There are sundry other natural substances which are nearly
pure silica, and when these are obtainable at a low price they are suitable
to be used as "decomposing substances." There are sundry natural sub-
stances which contain silica and alumina (such as blay slate) which can be
obtained in the form of lumps and nodules at a low cost, and are suitable
to be used as "decomposing substances" for the purposes of my Invention.
Ordinary clay when formed into dry lumps may also be used for such
purpose. There are sundry other natural substances (such as felspar, granite)
which contains silica and alumina, and which also contains some soda or
potassa. These are obtainable in the form of lumps or nodules at a low
cost. and are well adapted to be used as decomposing substances" for
the purpose of my Invention; when so used, the soda or potassa previously
existing in such substances is obtained in the mixed silicate and aluminate
produced. The precipitated silica or alumina or mixed precipitates of silica

page_text: and alumina obtained by decomposing silicates or aluminates of soda or of
potassa, or mixtures of silicates and aluminates of soda or of potassa, by
carbonic acid, as herein-before mentioned, may be obtained in, the state of
lumps or pieces by drying and compression or by other means, and then
become suitable to be used as "decomposing substances" for the purposes
of my Invention.
I have herein-before described the means which I consider to be best
adapted for effecting the objects of my Invention, but I do not confine myself
to the employment of the precise means herein indicated, as these may be
varied to some extent without deviating from the nature of my Invention; I
claim as my Invention secured to me by the herein-before in part recited
Letters Patent,-
Firstly, the decomposition of chloride of sodium and chloride of potassium
for the production of certain compounds of soda or of potassa (herein-before
defined), by causing such chlorides, or one of them, when in the state of
vapor mixed with the vapour of water, and mixed with gaseous products of
the combustion of fuel, to be brought into contact at an intense heat with
lumps or pieces of certain solid substances (herein-before defined as "decom-
posing substances") in such manner as to provide for such mixture of vapours
and gaseous bodies filtering or flowing through interstices existing between
the said lumps or pieces of solid substances.
And, secondly, the construction of apparatus which provides for chloride of
sodium or chloride of potassium in the state of vapour mixed with vapour of
water, and mixed with gaseous products of the combustion of fuel, being
caused to filter or flow at an intense heat through interstices existing between
lumps or pieces of certain solid substances (herein-before defined) contained
in a lower of chamber, as herein-before described.
In witness whereof, I, the said William Gossage, have hereunto set my
hand and seal, the Seventeenth day of January, in the year of our
Lord One thousand eight hundred and sixty-three.
Witness,
FRED. WALKDEN,
66, Chancery Lane.
(4.8.)