IMPROVE- MENTS IN THE MANUFACTURE OF PHOSPHORET OF IRON, PHOSPHATE OF LINE, AND ALKALINE PHOSPHATES
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 "IMPROVE-
MENTS IN THE MANUFACTURE OF PHOSPHORET OF IRON, PHOSPHATE OF LINE,
AND ALKALINE PHOSPHATES."-A communication from abroad by Edouard
Aubertin, of Paris, France.
Sealed the 14th March 1865, and dated the 19th September 1864.
PROVISIONAL SPECIFICATION left by the said Richard Archibald Brooman
at the Office of the Commissioners of Patents, with his Petition, on the
19th September 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 PHOSPHURET OF IRON, PHOSPHATE OF
LINE, AND ALKALINE PHOSPHATES," to be as follows:-
This Invention mainly consists in a process for transforming fossil phosphates
into phosphates of soda or of lime commercially pure. If silica, iron, and coal
be added to the phosphate of lime, the proportions of these several substances
being combined in such manner that the silica can form with the lime a
fusible silicate, and that the coal be in sufficient quantity to reduce the
phosphoric acid of the phosphate, and if the mixture be submitted to fusion

page_text: for 4 or 5 hours there will be obtained phosphuret of iron and scoria or
dross.
In the nodules or lumps of fossil phosphate of lime there are, in addition to
the phosphate, silica and oxide of iron; generally the latter is not in sufficient
quantity, and it is necessary to add more. The quantity of phosphorus
which the nodules contain is ascertained by previous chemical analysis, and
a quantity of iron representing 3 times the weight of the phosphorus is
employed; account must be taken of the amount of iron which the nodules
already contain, and then there should be added only what is required to make
up the quantity above named.
The operation may be easily performed in a blast furnace such as is used for
making cast iron. The only difference between the two operations is, that in
the present case it is necessary to put into the furnace alternate layers of fuel
nodules, either whole or roughly crushed, and iron, the quantity of which is
determined as above mentioned. The iron may be replaced by cast iron or
by an oxide of iron, account being taken of the oxygen of the latter. Tho
phosphuret of iron thus obtained may be run into ingots, but generally it will
be found advantageous to terminate all the operation at once. The phosphuret
of iron in fusion on its exit from the blast furnace is brought directly upon sul-
phate of soda previously heated; the reaction is very quick, and may be explained
thus: The phosphuret of iron decomposes the sulphuric acid of the sulphate
of soda, combines with its oxygen to form phosphoric acid, while the reduced
sulphur combines with the iron, the phosphoric acid unites with the soda, and
a portion of the iron passes also into the state of peroxide at the expense of a
certain quantity of sulphuric acid. The solid mass resulting from this
operation is therefore composed of phosphate of soda, sulphuret and oxide of
iron; there are also small quantities of free soda, sulphuret of sodium,
sulphate of soda in excess, but in very minute proportions. The mixture is
submitted to washings to remove all the alkaline phosphate, which may be
afterwards crystallized. The residue is composed of sulphuret and oxide of
iron; the sulphuret of iron may be utilized by leaving it in heaps exposed to
the air, and sprinkling them occasionally with water; it is thus transformed
into sulphate of iron, which may be lixiviated and crystallizod. The oxide of
iron which remains after this last operation may be used in a fresh production
of phosphuret of iron.
Instead of obtaining phosphate of soda by crystallization, it is sometimes
more economical to precipitate the aqueous solution of this salt by a milk of
lime, phosphate of lime is thus produced, which is washed and then dried, the
liquid and the wash waters contain all the soda which was in the phosphate of

page_text: soda. This alkali may be obtained by evaporating to dryness, or if it is found
more advantageous, this alkali may be saturated with carbonic acid, and then
be concentrated to produce crystals of soda or salts of soda.
The sulphate of soda may be replaced by the following salts:-Sulphate of
potassa, bisulphato of soda or of potassa, azotate of soda or of potassa.
All natural and artificial phosphates with a base of lime or iron may be
treated in manner before described,
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 18th March 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 IIer most Excellent Majesty Queen Victoria, by Her Letters
Patent, bearing date the Nineteenth day of September, 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 PHOSPHURET OF IRON, PHOSPHATE OF LIME, AND ALKALINE PHOSPHATES,"
(communicated to me from abroad by Edouard Aubertin, of Paris, France,)
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 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 Archibald Brooman, do hereby
declare the nature of the said Invention, and in what mauuer the same

page_text: is to be performed, to be particularly described and ascertained in and by
the following statement thereof, that is to say :-
This Invention mainly consists in a process for transforming fossil phosphates
into phosphates of soda or of lime commercially pure. If silica, iron, and coal
be added to phosphate of lime, the proportions of these several substances
being combined in such manner that the silica can form with the lime a
fusible silicate, and that the coal be in sufficient quantity to reduce the phos-
phoric acid of the phosphate, and if the mixture bo submitted to fusion for four
or five hours, there will be obtained phosphuret of iron and scoria or dross.
In the nodules or lumps of fossil phosphate of lime there are, in addition to
the phosphate, silica and oxide of iron; generally the latter is not in sufficient
quantity, and it is necessary to add more. The quantity of phosphorus which
the nodules contain is ascertained by previous chemical analysis, and a quantity
of iron representing three and a half times the weight of the phosphorus is
employed; account must be taken of the amount of iron which the nodules
already contain, and then there should be added only what is required to mako
up the quantity above named.
The operation may be easily performed in a blast furnace such as is used
for making cast iron. The only difference between the two operations is, that
in the present case it is necessary to put into the fuanaco alternate layers of
fuel nodules, either whole or roughly crushed, and iron, the quantity of which
is determined as above mentioned. The iron may be replaced by cast iron or
by an oxide of iron, account being taken of the oxygen of the latter. The
phosphuret of iron thus obtained may be run into ingots, but generally it will
be found advantageous to terminate all the operation at onco. The phosphuret
of iron in fusion on its exit from the blast furnaco is brought directly upon
sulphate of soda previously heated; sulphate of soda may also be heated to
redness in a reverberatory furnace similar to an ordinary soda oven, and the
phospurct of iron in fusion poured upon it, or the phosphuret of iron may bo
reduced to a granular state, and pulverized soda mixed with it, and the mixturo
heated in a reverberatory furnace; the reaction is very quick, and may bo
explained thus: The phosphuret of iron decomposes the sulphuric acid of the
sulphate of soda, combines with its oxygen to form phosphoric acid, while the
reduced sulphur combines with the iron, the phosphoric acid unites with the
soda and a portion of tho iron passes also into the state of peroxide at the
expense of a certain quantity of sulphuric acid of the sulphate of soda. The
solid mass resulting from this operation is therefore composed of phosphate of
soda, sulphate and oxide of iron; there are also small quantities of free soda,
sulphuret of sodium, sulphate of soda in excess, but in very minute propor-

page_text: tions. The mixture is submitted to washings to remove all the alkaline
phosphate, which may be afterwards crystallized. The residue is composed of
sulphuret and oxide of iron. The sulphuret of iron may be utilized by leaving
it in heaps exposed to the air, and sprinkling them occasionally with water.
It is thus transformed into sulphate of iron, which may be lixiviated and
crystallized. The oxide of iron which remains after this last operation may
be used in a fresh production of phosphuret of iron.
Instead of obtaining phosphate of soda by crystallization, it is sometimes
more economical to precipitate the aqueous solution of this salt by a milk of
lime, phosphate of lime is thus produced, which is washed and then dried, the
liquid and the wash waters contain all the soda which was in the phosphate of
soda; this alkali may be obtained by evaporating to dryness, or if it is found
more advantageous, this alkali may be saturated with carbonic acid, and then
concentrated to produce crystals of soda or salts of soda.
The sulphate of soda may be replaced by the following salts :-Sulphase of
potassa, bisulphate of soda or of potassa, azotate of soda or of potassa.
All natural and artificial phosphates with a base of lime or iron may be
treated in manner before described.
Among other applications, the phosphuret of iron may be used for the
production of phosphorus; for this purpose it is sufficient to submit it to quick
redness under the action of sulphur, sulphuretted hydrogen, sulphuret of
carbon, or sulphurets capable of yielding a part of their sulphur, such as
metallic bisulphurets and alkaline polysulphurets.
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 phosphuret of iron, phosphate of lime, and alkaline phosphates substantially
in manner herein-before described.
In witness whereof, I, the said Richard Archibald Brooman, have here-
unto set my hand and seal, this Seventeenth day of March, One
thousand eight hundred and sixty-five.