IMPROVEMENTS IN THE MANUFACTURE OF FLUORIDE OF SILICIUM
Year: 1864

page_text: LETTERS PATENT to Richard Archibald Brooman, of 166, Fleet Street, in
the City of London, Patent Agent, for the Invention of "IMPROVEMENTS
IN THE MANUFACTURE OF FLUORIDE OF SILICIUM."-A communication from
abroad by Cyprien Marie Tessié du Motay, and Edouard Karcher, of
Saarbruck, Rhenish Prussia.
Sealed the 10th January 1865, and dated the 14th July 1864.
PROVISIONAL SPECIFICATION left by the said Richard Archibald Brooman
at the Office of the Commissioners of Patents, with his Petition, on the
14th July 1864.
I, RICHARD ARCHIBALD BROOMAN, of 166, Fleet Street, in the City of
London, Patent Agent, do hereby declare the nature of the said Invention
for "IMPROVEMENTS IN THE MANUFACTURE OF FLUORIDE OF SILICIUM," to be
as follows:-
When fluoride of calcium is added to silicious copper ores a certain quantity
of fluoride of silicium is disengaged. Gay Lussac has also shown that by
dissolving at a high temperature silicic acid with fluoride of calcium fluoride of
silicum is obtained, but the quantity of fluorine gained from the fluoride of
calcium to produce the fluoride of silicium is not more than 30 per cent. of
the total weight of the fluorine contained in the said fluoride of calcium.
The reaction hereafter described, and which is the base of the present
discovery enables me to obtain according to the proportions of the added

page_text: matters from 66 to 88 per cent. of the total weight of the fluorine contained
in the fluoride of calcium employed in the docimastic production of fluoride of
silicium.
By dissolving in a closed crucible, furnished with tubes, in presence of carbon
an intimate mixture of 11 equivalents of silica and 18 equivalents of fluoride
of calcium, I recover, 1st, four equivalents of fluoride of silicium, 66 per cent.
of the fluorine contained in the fluoride of calcium; 2nd, six equivalents of
oxide of carbon due to the reaction of the carbon on the oxygen of the silica
in presence of the fluorine in the fluoride of calcium. In this reaction,
heretofore unknown, the carbon acts as a reducing element of part of the
oxygen contained in the silica, and aids the direct union of the fluorine and
the silicium to produce fluoride of silicium. By proportionately increasing
the quantity of silica and of carbon without increasing the fluoride of calcium,
and by adding to the mixture to render it fusible, a corresponding proportion
of aluminous earth, I am enabled under the same circumstances to obtain 88
per cent. of the fluorine in the fluoride of calcium employed.
I obtain commercially on a large scale with similar products to those
obtained in the closed crucibles the reaction above described by one of the
two following methods:-
:
:
1st method.--I manufacture blocks containing 1-1 equivalents of silica and
18 equivalents of fluoride of calcium, 80 equivalents of carbon, and 4 or 5
parts of aluminous earth. I dry them, then dissolve them in a retort, or in a
cupola, fitted at its mouth with a condensing apparatus for transforming the
fluoride of silicium produced into hydro-fluo-silicic acid. In this method the
carbon employed for the reduction of the oxygen of the silica being contained
in the blocks, the coke or other fuel used to obtain the fusion of the gangue
does not exceed the quantity necessary to fuse the said gangue:
2nd method. In a blast furnace similar to those employed for the reduction
of iron ores, I reduce and dissolve blocks containing 11 equivalents of silica,..
18 of fluoride of calcium, and 4 to 5 parts of aluminous earth, by adding to
each charge of blocks a sufficient quantity of coke or other fuel to produce at;
the same time the reduction of the oxygen of the silica and the fusion of the
fluoric gangue. It is thought that in this method the oxide, of carbon
generated at the tuyere by the combustion of the fuel exercises as much as
the carbon a reducing action on the oxygen of the silica contained in the
fluoric gangue.

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent, filed
_ by the said Richard Archibald Brooman in the Great Seal Patent
Office on the 14th January 1865.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, RICHARD
ARCHIBALD BROOMAN, of 166, Fleet Street, in the City of London, Patent
Agent, send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her Letters
Patent, bearing date the Fourteenth day of July, in the year of our Lord
One thousand eight hundred and sixty-four, in the twenty-eighth year
of Her reign, did, for Herself, Her heirs and successors, give and grant
unto me, the said Richard Archibald Brooman, Her special licence that
I, the said Richard Archibald Brooman, my executors, administrators,
and assigns, or such others as I, the said Richard Archibald Brooman,
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
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 "IMPROVEMENTS IN THE MANU-
FACTURE OF FLUORIDE OF SILICIUM," (communicated to me from abroad by
Cyprien Marie Tessié du Motay and Edouard Karcher, of Saarbruck, Rhenish
Prussia,) upon the condition (amongst others) that I, the said Richard
Archibald Brooman, my executors or administrators, by an instrument in
writing under my, or their, or one of their hands and seals, should par
ticularly 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 imme-
diately after the date of the said Letters Patent.
_ NOW KNOW YE, that I, the said Richard Archibald Brooman, 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 thereof, that is to say:-
When fluoride of calcium is added to silicious copper ores a certain quantity
of fluoride, of silicium. is disengaged. Gay Lussac has also shewn that by
dissolving at a high temperature silicic acid with fluoride of calcium fluoride
of silicium is obtained, but the quantity of fluorine gained from the
fluoride of calcium to produce the fluoride of silicium is not more than thirty
per cent. of the total weight of the fluorine contained in the said fluoride
of calcium.

page_text: The reaction hereafter described, and which is the base of the present
discovery, enables me to obtain according to the proportions of the added
matters from 66 to 88 per cent. of the total weight of the fluorine contained
in the fluoride of calcium employed in the docimastic production of fluoride of
silicium..
By dissolving in a closed crucible, furnished with tubes, in presence of
carbon, an intimate mixture of eleven equivalents of silica and eighteen
equivalents of fluoride of calcium, I recover, 1st, four equivalents of fluoride
of silicium, 66 per cent. of the fluorine contained in the fluoride of calcium;
2nd, six equivalents of oxide of carbon, due to the reaction of the carbon on
the oxygen of silica in presence of the fluorine in the fluoride of calcium. In
this reaction heretofore unknown, the carbon acts as a reducing element of
part of the oxygen contained in the silica, and aids the direct union of the
fluorine and the silicium to produce fluoride of silicium. By proportionately
increasing the quantity of silica and of carbon without increasing the fluoride
of calcium, and by adding to the mixture to render it fusible a corresponding
proportion of aluminous earth, I am enabled under the same circumstances to
obtain 88 per cent. of the fluorine in the fluoride of calcium employed.
I obtain commercially on a large scale with similar products to those
obtained in the closed crucibles the reaction above described by one of the
two following methods:-
1st method. I manufacture blocks containing eleven equivalents of silica
and eighteen equivalents of fluoride of calcium, thirty equivalents of carbon,
and four or five parts of aluminous earth, I dry them, then dissolve them in a
retort or in a cupola, fitted at its mouth with a condensing apparatus for
transforming the fluoride of silicium produced into hydro-fluo-silicic acid. In
this method the carbon employed for the reduction of the oxygen of the silica
being contained in the blocks, the coke or other fuel used to obtain the
fusion of the gangue does not exceed the quantity necessary to fuse the
said gangue.
2nd method. In a blast furnace similar to those employed for the reduction
of iron ores, I reduce and dissolve block containing eleven equivalents of silica,
18 of fluoride of calcium, and four to five parts of aluminous earth, by adding
to each charge of blocks a sufficient quantity of coke or other fuel to produce
at the same time the reduction of the oxygen of the silica and the fusion of
the fluoric gangue. It is thought that in this method the oxide of carbon
generated at the tuyere by the combustion of the fuel exercises as much as
the carbon a reducing action on the oxygen of the silica contained in the
fluoric gangue.

page_text: From the foregoing facts it will be seen that carbon employed as an agent
for reducing the oxygen contained in silica dissolved and combined with
fluoride of calcium is an indispensable agent for dosimastically producing
fluoride of silicium on a commercial scale.
And having now described the nature of the said Invention, and in what
manner the same is to be performed, I declare that I claim, the manufacture
of fluoride of silicium by reducing the oxygen of silica by means of carbon, or
of carbonated compounds in presence of fluoride of calcium, substantially in
manner herein-before described.
In witness whereof, I, the said Richard Archibald Brooman, have here-
unto set my hand and seal, this Thirteenth day of January One
thousand eight hundred and sixty-five.