An IMPROVED PROCESS FOR THE PRODUCTION OF Aluminium
Year: 1873

page_text: LETTERS PATENT to Richard Werdermann, of Princes Street, in the
County of Surrey, Civil Engineer, for the Invention of "An
IMPROVED PROCESS FOR THE PRODUCTION OF Aluminium.”
PROVISIONAL SPECIFICATION left by the said Richard Werdermann
at the Office of the Commissioners of Patents, with his Petition,
on the 29th May 1873.
I, RICHARD WERDERMANN, of Princes Street, in the County of Surrey,
Civil Engineer, do hereby declare the nature of the said Invention for
" AN IMPROVED PROCESS FOR THE PRODUCTION OF ALUMINIUM," to be as
follows:-
The said Invention consists in a novel process for producing the metal
aluminium without employing metallic potassium or sodium.
I first convert by electrolysis chloride of sodium Na Cl (common
salt) into sub-chloride of sodium, Na, Cl, or (Na, Cl₂). This sub-chloride
of sodium is afterwards reduced to powder, and mixed with cryolite or

page_text: chloride of aluminium, or with the double chloride of aluminium and
sodium in a sufficient quantity for the reduction of the aluminium. This
mixture, to which I may add any suitable flux, is placed in a reverbera-
tory furnace heated to redness. The reaction is quickly effected.
soon as the mixture has melted I puddle it, and after leaving it at rest for
some time it is tapped or run out.
As
I may substitute for the sub-chloride of sodium the sub-fluoride of
sodium, Na, Fl (or Na, Fl), or the sub-chloride or the sub-fluoride of
potassium, obtained also by the electrolysis of the chloride or fluoride
of these radicals.
The reaction which takes place in treating for example the cryolite
may be represented by the following equation :-6 Na Fl Al, F16 + 6
Na, Cl
= 12 Na Fl + 6 Na Cl + 2 Al.
Slag.
Metal.
Cryolite.
The slag may
Sub-chloride of sodium.
serve for the manufacture of soda, whose value will nearly equal that of
the first materials. The equivalent of chlorine freed by the electrolysis
of the chlorides may be employed for the manufacture of chloride of
aluminium.
SPECIFICATION in pursuance of the conditions of the Letters Patent,
filed by the said Richard Werdermann in the Great Seal Patent
Office on the 28th November 1873.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, RICHARD
WERDERMANN, of Princes Street, in the County of Surrey, Civil Engineer,
send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her
Letters Patent, bearing date the Twenty-ninth day of May, in the
year of our Lord One thousand eight hundred and seventy-three, in
the thirty-sixth year of Her reign, did, for Herself, Her heirs and
successors, give and grant unto me, the said Richard Werdermann, Her
special licence that I, the said Richard Werdermann, my executors, admin-
istrators, and assigns, or such others as I, the said Richard Werdermann,
my executors, administrators, and assigns, should at any time agree with,
and no others, from time to time and at all times thereafter during the

page_text: 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 PROCESS
FOR THE PRODUCTION OF ALUMINIUM," upon the condition (amongst others)
that I, the said Richard Werdermann, my executors or administrators,
by an instrument in writing under my, or their, or one of their hands
and seals, 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 Richard Werdermann, do hereby
declare the nature of my 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 consists in a novel process for producing the metal
aluminium without employing metallic potassium or sodium.
I first convert by electrolysis the chloride of sodium Na Cl (common
salt) into sub-chloride of sodium, Na, Cl, or (Na, Cl₂). This sub-chloride
of sodium is then reduced to powder, and mixed with cryolite or chloride
of aluminium, or with the double chloride of aluminium and sodium in
a sufficient quantity for the reduction of the aluminium. This mixture,
to which I may add any suitable flux, is placed in a reverberatory
furnace heated to redness, wherein the reaction is quickly effected. As
soon as the mixture has melted I puddle it, and after leaving it at rest
for some time it is drawn out.
I
may substitute for the sub-chloride of sodium the sub-fluoride of
sodium Na, Fl (or Na, FL), or the sub-chloride or the sub-fluoride of
potassium obtained also by the electrolysis of chloride or fluoride of
these radicals.
The reaction which takes place in treating for example the cryolite
may be represented by the following equation:-6 Na Fl Al, Fl 6 + 6
Cryolite.
The slag may
Na, Cl
= 12 Na Fl + 6 Na Cl + 2 Al.
Slag.
Metal.
Sub-chloride of sodium.
serve for the manufacture of soda, whose value will nearly pay the
expense of the first materials. The equivalent of chlorine freed by the

page_text: electrolysis of the chlorides may be employed for the manufacture of
chloride of aluminium.
Having thus described my said Invention, and the manner of
performing the same, I wish it understood that I claim, the process for
the production of aluminium without the employment of metallic potas- t
sium or sodium, as herein described.
In witness whereof, I, the said Richard Werdermann, have hereunto
set my hand and seal, this Twenty-fifth day of November, in the
year of our Lord One thousand eight hundred and seventy-
three.
Witness,
WM. ROBT. LAKE,
8, Southampton Buildings,
London.
R. WERDERMANN. (L.S.)