IMPROVEMENTS IN MEANS AND APPARATUS FOR THE TREATMENT OF ALKALINE SALTS AT HIGH TEMPERATURE, APPLICABLE ALSO TO OTHER USES
Year: 1883

page_text: LETTERS PATENT to Camille Alphonse Faure of Paris in the Republic of
France for an Invention of "IMPROVEMENTS IN MEANS AND APPARATUS FOR
THE TREATMENT OF ALKALINE SALTS AT HIGH TEMPERATURE, APPLICABLE
ALSO TO OTHER USES
"
PROVISIONAL SPECIFICATION left by the said Camille Alphonse Faure at
the Office of the Commissioners of Patents on the 22nd November 1883.
CAMILLE ALPHONSE FAURE of Paris in the Republic of France
"IMPROVEMENTS
IN MEANS AND APPARATUS FOR THE TREATMENT OF ALKALINE SALTS AT HIGH
TEMPERATURE APPLICABLE ALSO TO OTHER USES
"
This invention has for its object improvements in means and apparatus for the
treatment of alkaline salts at high temperature applicable also to other uses.
I treat alkaline earths and salts by a pyro-electric process, and especially I treat
carbonate of soda with a view to obtaining metallic sodium.
This is an improvement on the invention already patented by me N° 6058 in the
year 1882.
I build a furnace or rather a reverberatory vessel consisting in a sole piece or
pan closed in by side walls and covered with a dome. These parts are preferably
of compressed magnesia or such like refractory material not attacked by melted
soda. Embedded in the material forming the bottom of the pan are electric
conductors which terminate on the sides in pole pieces to which are attached the
conducting wires or mains. The passage of a current of electricity heats the
conductors and also the vessel and the material to be treated which is enclosed in
the covered pan. Suitable openings are provided in the apparatus for the introduc-
tion of the material, the escape of gas and vapour of sodium which are led to a
condenser similar to that used in the ordinary manufacture of sodium. A hole
may be left in the bottom pan for the discharge of scoria or other material as for
example aluminium if the vessel is used for the reduction of this metal from its
compounds.
In lieu of embedding totally the electric conductors they may be partially
embedded or may be laying on the surface of the pan or the pan itself may be a
conductor of electricity

page_text: For obtaining sodium I generally use a mixture of carbonate of soda and fine.
pure carbon such as lamp black which I introduce red hot for economy's sake. For
this preliminary heating of the materials I employ cylinders or tubes made of
compressed magnesia. They may be heated by the combustion of the waste
gases from a furnace; in these the cold material is prepared. Lately I have
been able to obtain suitable tubes made of compressed magnesia, a thing hitherto
unknown.
The conductors embedded in the pan may be iron, carbon, platinum, lead or such
convenient material.
In order to maintain the shape of my reducing furnace under the distorting
effects of heat I enclose it in a cast iron box bolted together with insulating
material between the bolts and flanges that the current may not be wastefully
expended. This also prevents any access of air to the charge in the furnace or any
loss of material.
As in my previous Patent I sometimes introduce into the furnace a stream of
gas such as volatile hydrocarbon to help the reaction.

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent filed
by the said Camille Alphonse Faure in the Patent Office on the 22nd May.
1884.
"
CAMILLE ALPHONSE FAURE of Paris in the Republic of France IMPROVEMENTS
IN MEANS AND APPARATUS FOR THE TREATMENT OF ALKALINE SALTS AT HIGH
TEMPERATURE APPLICABLE ALSO TO OTHER USES
"
This invention has for its object improvements in means and apparatus for the
treatment of alkaline salts at high temperature applicable also to other uses.
I treat alkaline earths and salts by a pyro-electric process and especially I treat
carbonate of soda with a view to obtaining metallic sodium.
This is an improvement on the invention already patented by me N° 6058 in the
year 1882.
I build a furnace or rather a reverberatory vessel consisting in a sole piece or
pan closed in by side walls and covered with a dome. These parts are preferably
of compressed magnesia or such like refractory material not attacked by melted
soda. Imbedded in the material forming the bottom of the pan are electric
conductors which terminate on the sides in pole pieces to which are attached the
conducting wires or mains. The passage of a current of electricity heats the
conductors and also the vessel and the material to be treated which is enclosed in
the covered pan. Suitable openings are provided in the apparatus for the introduc-
tion of the material, the escape of gas and vapour of sodium which are led to a
condenser similar to that used in the ordinary manufacture of sodium. A hole
may be left in the bottom pan for the discharge of scoria or other material as for
example aluminium if the vessel is used for the reduction of this metal from its
compounds.
In lieu of imbedding totally the electric conductors they may be partially
imbedded or may be laying on the surface of the pan or the pan itself may be a
conductor of electricity.
For obtaining sodium I generally use a mixture of carbonate of soda and fine
pure carbon such as lamp black which I introduce red hot for economy sake. For
the preliminary heating of the materials I employ cylinders or tubes made of
compressed magnesia. They may be heated by the combustion of the waste
gases from a furnace in these the cold material is prepared. Lately I have
been able to obtain suitable tubes made of compressed magnesia a thing hitherto
unknown.
The conductors imbedded in the pan may be iron, carbon, platinum, lead or such
convenient material.
In order to maintain the shape of my reducing furnace under the distorting
effect of heat I enclose it in a cast iron box bolted together with insulating material
between the bolts and flanges that the current may not be wastefully expended.
This also prevents any access of air to the charge in the furnace or any loss of
material.
As in my previous Patent 1 sometimes introduce into the furnace a stream of
gas such as volatile hydrocarbon to help the reaction.
In order that my said invention may be most fully understood and readily
carried into effect I will proceed to describe the Drawings hereunto annexed.
DESCRIPTION OF THE DRAWINGS
い

page_text: B the body formed of magnesia or other earth of a refractory and insulating
material. The body is made of considerable thickness to avoid loss of heat.
C is the dome or cover of the furnace it also is made of magnesia or other
refractory material.
D is an opening by which the matters to be treated are introduced, they are
brought to the furnace preferably in a heated or fused state. In some cases an
opening in the bottom. is also provided for the withdrawal of materials from the
furnace.
E is an opening for the escape of gas and vapours.
F is a metallic casing protecting the refractory lining of the furnace and that of
the dome or cover.
G. G. are electric conductors of carbon, platinum, lead, iron or other suitable
conducting material they are placed or embedded in the sole of the furnace and
they become highly heated by the passage of the electric current.
HH are pole pieces of iron or other suitable matter.
S is the sole of the furnace.
Figures 3 and 4 show modifications, of which it is sufficient to say that S¹ in
Figure 3 is a sole prepared with bars of iron or other metal sunk into the sole.
and serving as the electric conductors. S in Figure 4 is a bottom with an iron
covering or it may be a covering of carbon or carbon mixed with magnesia. The
sides of the furnace may be prepared likewise with conducting carbon mixed with
magnesia or heated by conductors buried in the sides.
The material introduced by the opening D such for example as a mixture of
carbonate of soda and lamp black or pure carbon is thus enclosed within a space
in which an external temperature can be obtained. In some cases I introduce
hydro carbon gases to aid the reaction. The vapours of sodium which escape
by the opening E pass away to and are condensed within a suitable condenser
or receiver generally the flat condenser employed at the present time in the
manufacture of this metal. Other alkaline metals can be similarly produced.
As a measure of economy and in order not to have to supply by electricity
anything but the last increments of beat necessary to obtain the excessive tempe->
rature required I raise the materials to a high heat before introducing them into
the furnace I effect this heating of the materials in cylinders of magnesia exposed
to the heat of the furnace..
Separate conductors may be employed or a single conductor of considerable.
length arranged in a serpentine form and connected at its two ends only to pole
pieces. The serpentine may be formed of straight parallel bars or as a spiral.
Figures 5. 6 and 7 show a furnace heated by a zigzag conductor upon the bed.
The electric current in passing from the pole piece H to the opposite pole piece H'
raises the whole length of the conductor to a very high temperature and this
according to the material of which the conductor is formed may in some cases much
exceed its melting point.
In this case I separate the spirals of the conductor by slightly raised parts of the
refractory sole S. The electric conductor thus provided upon the sole of the furnace
or a little below it may be of any material and of any form so long as when
traversed by a powerful electric current it developes on the sole of the furnace the
extreme temperature necessary to the dissociation and volatilization of sodium, or
for the heating and reduction of other alkaline metals and like matters.
Thus by means of magnesia and an electric conductor or several electric.
conductors I form my electric furnace which I can apply to all operations of
heating fusion and dissociation. But especially I apply it to the manufacture
of sodium by the means indicated..
Lime may also be employed. The magnesia or lime is either agglutinated by.
pressure or pressure and heat or downright melted by pyro electric means and cast
into slabs,

page_text: Having thus described the nature of my said invention and the manner of
performing the same I would have it understood that I claim:-
First The application of magnesia or lime which is unchangeable by metals
such as sodium to the construction of high temperature furnaces and heating
apparatus as described.
Second-A furnace of magnesia or other refractory earth with electric con-
ductors in the sole or walls yielding a high temperature and applicable particularly
to the treatment of alkaline metals.
Third The application of the said furnace in the manner described to the
manufacture of sodium and the alkaline metals.
Fourth-The magnesian furnace with its electrical conductors and iron casing
substantially as described.
Fifth The application of magnesia to the manufacture of cylinders or retorts
for heating the materials preparatory to their admission to the electrically heated
sole of the furnace.
Sixth. The manufacture of sodium by the pyro electric means herein described.
In witness whereof I the said Camille Alphone [sic] Faure have hereunto set my
hand and seal this tenth day of May in the year of our Lord One thousand eight
hundred and eighty four.
2
LADE