Improvements in and connected with the Manufacture of Aluminium and other Light Metals.
Year: 1886

page_text: Improvements in and connected with the Manufacture of Aluminium
and other Light Metals.
I FRANCIS IGNATIUS RICARDE SEAVER of the Conservative Club, St. James Street
in the County of Middlesex, F.R.S. Edinburgh &c. do hereby declare the nature of
this invention to be as follows:-
This invention relates to the manufacture of Aluminium and other light metals from
the minerals or substances in or with which they are combined. The invention consists
essentially in the manufacture or in effecting the separation of such metals by means
of the action of an electric current all as hereinafter more fully set forth it being
understood that although the process is described with reference to the production
of Aluminium it may also be employed for the production of certain other light
metals.
To carry the invention into effect I take a box or vessel and line it with any suitable
material, but preferably with Bauxite and aluminous clay. Into this vessel I introduce
electrodes connected with a dynamo or other source of electricity, and the arrange-
ment may be conveniently carried out by introducing the negative electrodes at the
bottom and the positive at the top, and coupling them in multiple arc, as to obtain
the best results at the lowest temperature, a given intensity and quantity of current
are essential. The carbon electrodes should be so arranged that the arc will be formed
within the vessel. To obtain metallic aluminium I employ a double fluoride of
aluminium and sodium and this may be either the natural substance known as Cryolite
or the manufactured article as commercially supplied, but in either case the double
fluoride treated should be free from iron, sulphur and other well known deleterious
substances. The material when in a dried or calcined state is ground until about as
fine as sand and is then packed in the vessel around the electrodes.-This being done
the electric current is switched on and the mass gradually heats and finally melts

page_text: about the are between the electrodes, the double fluorides being decomposed and
metallic aluminium deposited at the negative pole, and a double fluoride of sodium left
in the mass. The current is then shut off, and the materials allowed to cool, after
which the mass is broken up and the metallic aluminium separated therefrom while
the residual slag or bye product may be sold as a commercial article or reconverted
into a double fluoride of aluminium and sodium by fusing it with Bauxite or pure
alumina. When using Bauxite or aluminous clay as a lining for the vessel a certain
quantity of the necessary alumina to form a double fluoride of aluminium and sodium
will be taken up by the free fluorine present thus reforming the necessary compound
which in its turn is decomposed and gives up metallic aluminium.
Dated 29th day of June 1886.
PHILIP M. JUSTICE,
55 & 56, Chancery Lane, London,
Agent for the Applicant.

page_text: COMPLETE SPECIFICATION.
Improvements in and Connected with the Manufacture of Aluminium
and other Light Metals.
I FRANCIS IGNATIUS RICARDE SEAVER of the Conservative Club, St. James Street
in the County of Middlesex, F.R.S. Edinburgh &c. do hereby declare the nature of
this invention (a communication to me from abroad by Dr. Edward Caspar Kleiner-
Fiertz of Zurich in the Swiss Republic) and in what manner the same is to be
performed, to be particularly described and ascertained in and by the following
statement:-
This invention relates to the manufacture of aluminium and other light metals from
the minerals or substances in or with which they are combined. The invention consists
essentially in the manufacture or in effecting the separation of such metals by means
of the action of an electric current all as hereinafter-more fully set forth it being
understood that although the process is described with reference to the production of
aluminium it may also be employed for the production of certain other light metals
such as sodium and magnesium.
To
To carry the invention into effect I take a box or vessel and line it with any suitable
material, but preferably with Bauxite or aluminous clay. Into this vessel I introduce
electrodes preferably formed of pure and very compact carbon and connected with a
dynamo or other source of electricity, and the arrangement may be conveniently
carried out by introducing the negative electrodes at the bottom and the positive at
the top and coupling them into multiple arc, as to obtain the best results at the lowest
temperature a given intensity and quantity of current are essential. The carbon
electrodes should be so arranged that the arc will be formed within the vessel.
obtain metallic aluminium I employ a double fluoride of aluminium and sodium and
this may be either the natural substance known as cryolite or the mauufactured article
as commercially supplied, but in either case the double fluoride treated should be free
from iron, sulphur and other well known deleterious substances. The material when
in a dried or calcined state is ground until about as fine as sand and is then packed in
the vessel around the electrodes. This being done the electric current is switched on
and the mass gradually heats and finally melts about the arc between the electrodes,
the double fluorides being decomposed and metallic aluminium deposited at the
negative pole, and a double fluoride of sodium with, in some cases certain undecom-
posed cryolite, left in the mass. The current is then shut off, and the material allowed
to cool, after which the mass is broken up and the metallic aluminium separated there-
from while the residual slag or bye product may be sold as a commercial article or
reconverted into a double fluoride of aluminium and sodium by fusing it with
Bauxite or pure alumina. When using Bauxite or aluminous clay as a lining for the
vessel a certain quantity of the necessary alumina to form a double fluoride of
aluminium and sodium will be taken up by the free fluorine present thus re-forming
the necessary compound which in its turn is decomposed and gives up metallic
aluminium.
In order that my invention may be clearly understood I refer to the accompanying
drawings which form part of this Specification and in which

page_text: Figure 1 represents a side elevation Figure 2 an end elevation and Figure 3 a plan
on the line x x of the arrangement of apparatus which I consider suitable for carrying
my invention into effect. The framework or trolley A carries the box or vessel B
lined with Bauxite or other suitable material C.
The negative carbons a a are carried in suitable holders & resting on the platform D
which may be made adjustable if desired and raised or lowered by worm and screw
gear. The positive carbons g g are preferably carried in holders d adapted to receive
a number of carbons as shown, in order that the current may act on the contained
material at a number of points around the negative carbons a a The carbon
holders are carried by rods e, f, suitably counterweighted or otherwise made
adjustable and connected to the positive conductor from the dynamo.
As
The box B having been filled with powdered cryolite or double fluoride of aluminium
and sodium the current is switched on, and the electric arc having been established
between carbons g and a the cryolite or double fluoride is rapidly melted and decom-
posed the current being regulated so as to keep the mass in a fluid condition.
this treatment continues it will be found that the separated metallic aluminium will
collect around the negative carbon at the bottom of the bath in the form of globules or
balls of varying size.
The separation being completed at any one set of electrodes, the current is there
cut off and the mass allowed to cool after which it is broken up and the metallic
aluminium separated therefrom.
The above is a simple and effective arrangement of the apparatus but in order to
lessen the waste of the carbons I prefer to use in connection with the said apparatus
the improvements in respect of which application for Letters Patent was made on the
24th day of November 1886 under No. 15,322.
Other light metals, such as sodium and magnesium may be obtained in a similar
manner from their respective double fluorides and chlorides, but these metals having
a lower specific gravity, rise to the surface of the molten bath and must be prevented
from burning there. For this purpose the top of the cathode may be covered with a
bell or other shaped vessel so as to exclude access of air. The metal separated will
rise into said vessel. The small amount of oxygen in the air originally contained in
said vessel is quickly consumed, and the access of air being excluded, further,
combustion of the metal is impossible.
I am aware that prior to my invention it has been proposed to melt steel and other
substances by aid of the electric arc, and also to melt cryolite by means of an external
fire and while in a molten condition to decompose it by the action of an electric current,
and I do not claim either of these processes as part of my invention, but having now
particularly described and ascertained the nature of my said invention and in what
manner the same is to be performed as communicated to me by my foreign
correspondent I declare that what I claim is :-
:-
The improvements in the manufacture of metallic aluminium and other light metals
from their more easily fusible compounds as herein before described which consist in
fusing and decomposing such compounds in an aluminous lined of other vessel by the
direct action of the electric current and without the aid of external heat substantially
as set forth.
PHILIP M. JUSTICE,
55 & 56, Chancery Lane London,
Agent for the Applicant.