IMPROVEMENTS IN THE PRODUCTION OF ALUMINIUM AND ITS ALLOYS, AND IN THE PRODUCTION OF OTHER METALS, THE OXIDES OF WHICH ARE NOT REDUCIBLE BY CHARCOAL
Year: 1858

page_text: LETTERS PATENT to John Henry Johnson, of 47, Lincoln's Inn Fields,
in the County of Middlesex, and of 166, Buchanan Street, in the City of
Glasgow, North Britain, Gentleman, for the Invention of "IMPROVEMENTS
IN THE PRODUCTION OF ALUMINIUM AND ITS ALLOYS, AND IN THE PRODUCTION
OF OTHER METALS, THE OXIDES OF WHICH ARE NOT REDUCIBLE BY CHARCOAL."
-A communication from Louis Philippe Bernard Edouard Cumenge, of
Paris, in the Empire of France, Mining Engineer.
Sealed the 20th August 1858, and dated the 6th March 1858.
PROVISIONAL SPECIFICATION left by the said John Henry Johnson at
the Office of the Commissioners of Patents, with bis Petition, on the
6th March 1858.
I, JOHN HENRY JOHNSON, of 47, Lincoln's Inn Fields, in the County of
Middlesex, and of 166, Buchanan Street, in the City of Glasgow, North
Britain, Gentleman, do hereby declare the nature of the said Invention for
"IMPROVEMENTS IN THE PRODUCTION OF ALUMINIUM AND ITS ALLOYS, AND IN THE
PRODUCTION OF OTHER METALS, THE OXIDES OF WHICH ARE NOT REDUCIBLE BY
CHARCOAL," a communication from Louis Philippe Bernard Edouard Cumenge,
of Paris, in the Empire of France, Mining Engineer, to be as follows:-
This Invention relates to a system or mode of treating or reducing the ores
of metals which have not hitherto been in common use, as for example
aluminium, by inexpensive reagents, thereby dispensing with those costly
reagents hitherto used, such as chlorine and sodium, and consequently render-
ing the production of these metals a simple and economical process.

page_text: The principle or main feature of this Invention consists in the use as
auxiliary agents for the production of aluminium and other similar metals, of
sulphur, charcoal, or coke and atmospheric air, the apparatus employed
differing but slightly from those ordinarily used in metallurgical processes.
The principles upon which the process is based are,-
First, the sulphuret of aluminium is brought to a metallic state with a
liberation of sulphuretted hydrogen by heating it in a dry current of hydrogen.
Second, the sulphuret of aluminium produced from metallic aluminium by
reaction on the dry sulphate of alumina or on alumina with liberation of
sulphurous acids by heating them to a red heat in an inoxidising atmosphere.
The sulphuret of aluminium is reduced by a dry process by means of known
metals such as iron, copper, and zinc.
In practically carrying out this Invention, I prefer to employ a clay retort
similar to those used in gasworks, and I fill one-half of its length with
charcoal or coke, and the other half with alumina, a small orifice being left at
each end of the retort. The retort is now heated to redness and a quantity
of sulphur necessary to carry on the reaction is introduced therein through the
orifice at the charcoal end of the retort, the gases which are generated therein
passing off by the orifice at the opposite end of the retort. The sulphur
becomes volatilized, and in its passage over the incandescent charcoal is
transformed into sulphuret of carbon which passes over the heated aluminium.
The carbon takes up the oxygen and forms carbonic oxide gas, whilst the
sulphur settles upon the metallic aluminium. The sulphuret of aluminium thus
produced may be treated either by reaction or reduction.
First, by reaction in a reverberatory furnace in an inoxidising atmosphere
by mixing it with a sufficient quantity of dry sulphate of alumina or alumina
itself to cause the oxygen of the sulphate or of the oxide added to be equal to
that necessary for oxidising the sulphur of the sulphuret to the state of
sulphurous acid. The aluminium remains in a metallic state, and the metal
with which it is to be alloyed may now be added.
Second, by reduction with the aid of hydrogen, which expels all the sulphur
from the sulphuret in the form of sulphuretted hydrogen. The hydrogen may
be produced in any well-known manner, but I have found the most economical
mode to be the action of steam on incandescent charcoal.
Lastly, the reduction by any of the known metals may be effected in the
furnaces and after the manner already practised for other metals.
Good metallic alloys may be obtained by the action of aluminium or of
sulphate of alumina on the natural or artificial sulphurets of other metals, with
or without the mixture of charcoal, for producing double sulphurets, to which

page_text: are applicable the same principles of treatment as those for the sulpburet of
aluminium. This process is equally applicable to the treatment of other metals
the oxides of which are not reducible by charcoal, and for which it is requisite
to use sulphur if the costly employment of sodium is to be dispensed with.
SPECIFICATION in pursuance of the conditions of the Letters Patent, filed
by the said John Henry Johnson in the Great Seal Patent Office on
the 6th September 1858.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, JOHN
HENRY JOHNSON, of 47, Lincoln's Inn Fields, in the County of Middlesex, and
of 166, Buchanan Street, in the City of Glasgow, North Britain, Gentleman,
send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her Letters
Patent, bearing date the Sixth day of March, in the year of our Lord One
thousand eight hundred and fifty-eight, in the twenty-first year of Her reign,
did, for Herself, Her heirs and successors, give and grant unto me, the said
John Henry Johnson, Her special license that I, the said John Henry
Johnson, my executors, administrators, and assigns, or such others as I, the
said John Henry Johnson, my executors, administrators, or 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 "IMPROVE-
MENTS IN THE PRODUCTION OF ALUMINIUM AND ITS ALLOYS, AND IN THE PRODUCTION
OP OTHER METALS, THE OXIDES OF WHICH ARE NOT REDUCIBLE BY CHARCOAL," a
communication from Louis Philippe Bernard Edouard Cumenge, of Paris, in
the Empire of France, Mining Engineer, upon the condition (amongst others)
that I, the said John Henry Johnson, 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 I, the said John Henry Johnson; do hereby
declare the nature of the said Invention, and in what manner the same is to
be performed, to be particularly described and ascertained in and by the
following statement:
The said Invention relates to the treatment of the sulphurets of metals

page_text: which have not hitherto been in common use, as, for example, aluminium, by
inexpensive methods, whereby costly reagents hitherto employed, such as
chlorine and sodium, are dispensed with, and the production of these metals
is consequently rendered much simpler and cheaper.
The Invention consists of two heads; the first head relates to the obtainment
of aluminium from the sulphuret of that metal, by heating such sulphuret along
with anhydrous sulphate of alumina or with anhydrous alumina in a non-
oxydising atmosphere; and the second head relates to the obtainment of
aluminium from the sulphuret of that metal by passing a dry current of
hydrogen through or into it when heated to a red heat, whilst the air is
excluded. With regard to the first head, I employ the sulphuret of aluminium
produced by any known method, for example, by passing the vapour of
sulphuret of carbon over alumina heated to a red heat in a suitable apparatus.
This sulphuret must be placed in a furnace of suitable form and size along
with such a proportion of sulphate of alumina as that the oxygen given out
when heat is applied may by union with the sulphur of the ingredients form
sulphurous acid. The proper proportion can be easily calculated by chemists
and metallurgists. The mixture must be raised to a high temperature in a
non-oxydising atmosphere; whereupon the whole of the sulphur and the oxygen
contained in the ingredients will disappear in the form of sulphurous acid, and
the aluminium of the ingredients will remain behind in the state of metal.
In place of sulpe of alumina, anhydrous alumina may be employed if care
be taken to proportion the alumina to the sulphuret, so that the oxygen of the
former may comoine with and carry off the sulphur of the latter in the state
of sulphurous acid. It is desirable that the operator should assist the process
by keeping the ingredients well stirred. When the aluminium has been
obtained it may be treated in a similar way to that practised in puddling iron,
and it may then be either rolled or subjected to the hammer.
At the termination of this operation the metal with which it is desired to
make an alloy of a more fusible nature than the pure metal may be introduced,
and, if thought desirable, small quantities of potassium or sodium may be added
in order to obtain aluminium having certain qualities distinguishing it from
the aluminium of commerce. In case an alloy is contemplated, I recommend
a metallic oxide to be introduced into the furnace at the conclusion of the
operation, in order to consume the carbon that might be held in combination
by the aluminium; the oxygen of the oxide forming oxide of carbon with
the carbon of the carburet, and the two metals combining into an alloy. The
fluxes to be used will necessarily vary according to the materials to be operated
on, a
and these are well known to persons engaged in operations of this nature.

page_text: With regard to the second head of Invention, I employ, as before, sulphuret
of aluminium produced by any known method, and placing it in a crucible or
other receptacle of suitable size and form, I subject it to a red heat whilst the
atmosphere is excluded, and then pass dry hydrogen through or into it; the
sulphur of the sulphuret will thereupon be carried off in the form of sulphuretted
hydrogen. In case the sulphuret of any other metal should be present, an
alloy of the two metals will thus be obtained. If the combined sulphuret
should simply be reduced to a minimum of sulphurization by the hydrogen, the
aluminium may be separated from the proto-sulphuret by a separate process
of melting. The hydrogen employed in this process may be economically
obtained by passing the steam over red-hot coke or charcoal.
The sulphurets of other little known metals having properties similar to
those of aluminium may be treated by either of the methods above described.
I wish it to be understood that I do not claim the production of sulphuret
of aluminium, since my processes commence with the treatment of the
sulphuret produced by any method whatever; neither do I claim any form of
apparatus, inasmuch as there are several suitable forms of apparatus at present
in use for similar purposes, for example, certain furnaces employed in the
treatment of copper will serve very well. I may, however, observe that the
size of grate and heating surface of the furnace (speaking with reference to the
process described under the first head of Invention) ought to be so proportioned
as to throw out a good white heat, and the fuel should be laid on the bars in
a sufficient quantity to convert the bulk of the air passing through it into
oxide of carbon. The flame ought to be a good reducing flame and non-
oxydising.
In witness whereof, I, the said John Henry Johnson, have hereunto
set my hand and seal, this Third day of September, One thousand
eight hundred and fifty-eight.
J. HENRY JOHNSON. (L.S.)