IMPROVEMENTS AND MODIFICATIONS IN THE TREATMENT OF PHOSPHATE IN GENERAL, AND IN THE PRODUCTION AND PURIFICATION OF PHOSPHORIC ACID AND ITS COMBINATIONS
Year: 1872

page_text: ETTERS PATENT to Alexander Browne, of the Firm of Browne and
Company, Patent Agents, of 85, Gracechurch Street, in the City of
London for the Invention of " IMPROVEMENTS AND MODIFICATIONS IN
THE TREATMENT OF PHOSPHATE IN GENERAL, AND IN THE PRODUCTION AND
PURIFICATION OF PHOSPHORIC ACID AND ITS COMBINATIONS." -A communi-
tion from abroad by Henri Storck, Edouard Hentsch, Auguste
Hentsch, André Lutscher, and Frédéric Grininger, all of Paris, in
the French Republic, constituting the Firm of Storck and
Company.
PROVISIONAL SPECIFICATION left by the said Alexander Browne
at the Office of the Commissioners of Patents, with his Petition,
on the 30th July 1872.
I, ALEXANDER BROWNE, of the Firm of Browne and Company, Patent
Agents, of 85, Gracechurch Street, in the City of London, do hereby
declare the nature of the said Invention for "IMPROVEMENTS AND MODI-
FICATIONS IN THE TREATMENT OF PHOSPHATE IN GENERAL, AND IN THE PRODUCTION
AND PURIFICATION OF PHOSPHORIC ACID AND ITS COMBINATIONS," a communica-

page_text: tion from abroad by Henri Storck, Edouard Hentsch, Auguste Hentsch,
André Lutscher, and Frédéric Grininger, all of Paris, in the French
Republic, constituting the Firm of Storck and Company, to be as
follows
Republic, constituting the Firm of Storck and Company, to be as
follows:
This Invention consists,―
First. In employing sulphate of ammonia to produce alkaline
phosphates of the same base by double decomposition by treating the
acid phosphates of lime, barytes, strontium, or lead with sulphuric acid or
one or other of the oxides above mentioned.
'
Secondly. In the formation of the aforesaid acid phosphates, also
alkaline, earthy and metallic acids, especially the acid phosphate of lime
in order to adapt them to the double decomposition in question by
adding lime or carbonate of lime, or one or other of the carbonates of the
oxides thereof to the acid liquor obtained from phosphates or bones
when acted upon by sulphuric acid in order to produce a liquor of a
degree of saturation suitable for the double decomposition in question.
Thirdly. The extraction of the sulphuric acid contained in alkaline
phosphates, solutions, superphosphates and phosphoric acid by so
treating phosphates of lead, phosphates of barytes, or phosphate of
strontium, whether the said phosphates be products before hand or be
formed at the same time as the liquor by an addition of caustic barytes,
carbonate of barytes, or by the oxide or carbonate of lead or other
combination of lead or barytes, or by corresponding salts or oxides of
strontium.
Fourthly. The extraction of iron and alumine from the soluble silex
and insoluble phosphates by methodic precipitation occasioned by
neutralizing the desulphorized and still acid liquor obtained by this
improved method.
Fifthly. The extraction and precipitation of the phosphoric acid of
the liquor properly concentrated into the state of basic phosphate of
ammonia 3 AzНдОPhОs by the addition of ammonia to the liquor,
according to the treatment before described under paragraphs 1, 2, 3, 4.
Sixthly. In the application of gaseous ammonia for the production of
the precipitate 3AZH,ОPhOs above-mentioned.
11
Seventhly. In the subsequent treatment of the insoluble residuary
precipitates according to the treatment described at paragraph 4, and

page_text: then utilization of the manufacture of soluble alkaline phosphates by
boiling them with caustic alkalies or alkaline salts, for example
carbonate of potash or soda.
I now proceed by way of example to describe the mode of manu-
facturing the tribasic phosphate of ammonia 3AzH"OPHO. Accord-
ing to this Invention I take a certain quantity of sulphuric acid, I
empty into this acid gradually phosphorites, coprolytes, calcined bones,
animal charcoal, and such like matters, stirring the decomposing
phosphates into a pulverulent state, and after they have been sufficiently
stirred and mixed together I decant the liquor. I concentrate this
liquor, and having brought it to the required degree of concentration
introduce a quantity of lime or carbonate of lime so as to convert
completely all or nearly all of the free phosphoric acid into acid
phosphate of lime, I then treat this liquor either cold or hot with
sulphate of ammonia, and thus effect the double decomposition above-
mentioned, that is to say, I produce in the liquor a certain quantity of
acid phosphate of ammonia and a precipitate of sulphate of lime which
I separate by any known means.
I obtain a liquor containing acid phosphate of ammonia mixed with
impurities in the reaction, sulphuric acid, and sulphates, and the natural
impurities, namely, iron, soluble silex, alumine, et cetera, which it serves
to eliminate, but the greater part of the lime is got rid of. To effect
this and above all to get rid of the sulphuric acid, I treat the liquor with
phosphate of barytes, lead, or strontium which forms a corresponding
insoluble sulphate, or I form the said phosphates at the same time as
the liquor by adding thereto barium, lead, or strontium or their carbonates,
or other salts of barium, lead, or strontium capable of producing
phosphates of the above metals decomposable by sulphate of ammonia.
I separate the precipitate; then in order to eliminate the other
impurities I neutralize by ammonia; I thus separate them in a state of
precipitate. The liquor is thus formed solely of neutral phosphate of
ammonia. We either pass a current of ammoniacal gas or add
ammoniacal liquid to produce the tribasic phosphate 3AzH"OPho⁹.
The residue from the neutralization of the acid liquor above described
serves to produce phosphate of soda or potash. For this purpose I
operate as follows:-I boil the residue with an excess of soda, potash, or
carbonates of these bases or corresponding sulphurs (or else with other
salts of the above bases capable of producing decomposition at will, such

page_text: as silicates, borates, et cetera. I thus produce phosphate of soda or
potash at the expense of the phosphoric acid contained in the precipitate..
The soluble phosphates formed may be separated by filtration or other
means, and be purified by crystallization.
SPECIFICATION in pursuance of the conditions of the Letters Patent,
filed by the said Alexander Browne in the Great Seal Patent Office
on the 28th January 1873.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, ALEXANDER
BROWNE, of the Firm of Browne and Company, Patent Agents, of 85,
Gracechurch Street, in the City of London, send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her
Letters Patent, bearing date the Thirtieth day of July, in the year of
our Lord One thousand eight hundred and seventy-two, in the thirty-
sixth year of Her reign, did, for Herself, Her heirs and successors, give
and grant unto me, the said Alexander Browne, Her special licence
that I, the said Alexander Browne, my executors, administrators, and
assigns, or such others as I, the said Alexander Browne, 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 AND MODI-
FICATIONS IN THE TREATMENT OF PHOSPHATE IN GENERAL, AND IN THE PRODUCTION
AND PURIFICATION OF PHOSPHORIC ACID AND ITS COMBINATIONS," a communica-
tion from abroad by Henri Storck, Edouard Hentsch, Auguste Hentsch,
André Lutscher, and Frédéric Grininger, all of Paris, in the French
Republic, constituting the Firm of Storck and Company, upon the
condition (amongst others) that I, the said Alexander Browne, 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 Alexander Browne, do hereby
declare the nature of the said Invention, and in what manner the same

page_text: by the following statement, that is to say :-
This Invention consists,―
First. In employing sulphate of ammonia to produce alkaline
phosphates of the same base by double decomposition in treating the
acid phosphates of lime, baryta, strontiane or lead with sulphuric acid.
Secondly. In the formation of the said acid phosphates, also alkaline,
earthy and metallic oxides, especially the acid phosphate of lime in
order to apply them to the double decomposition in question by adding
lime or any of the oxides above-mentioned, or carbonate of lime, or one
or other of the carbonates of the oxides thereof to the acid liquor
obtained from phosphorites or bones when acted upon by sulphuric acid
in order to produce a liquor of a degree of saturation suitable for the
double decomposition in question.
Thirdly. In the extraction of the sulphuric acid contained in solutions
of alkaline phosphates, superphosphates, and phosphoric acid by a
treatment with phosphates of lead, phosphates of baryta, or phosphate of
strontiane, whether the said phosphates are produced in the body of the
liquor before hand or are formed by an addition thereto of caustic
baryta, carbonate of baryta, or by the oxide or carbonate of lead or other
combination of lead or baryta, or by the corresponding salts or oxides of
strontiane.
Fourthly. In the extraction of iron and alumina from the soluble
phosphates by a methodic precipitation in neutralizing exactly the
desulphated but still acid liquor obtained by this improved method.
Fifthly. In the extraction and precipitation of the phosphoric acid
from the liquor properly concentrated in the state of basic phosphate
of ammonia (3AzH*OPhO) by the addition of ammonia to the liquor
resulting from the mode of treatment described under paragraphs 1, 2, 3, 4.
Sixthly. In the application of gaseous ammonia for producing the
above precipitate (3AzH*OPho³).
Seventhly. In a subsequent treatment of the insoluble residual
precipitates resulting from the mode of treatment described in paragraph
4, and their utilization in the manufacture of soluble alkaline phosphates
by boiling them with caustic alkalies or alkaline salts, for example
carbonate of potash or soda.

page_text: I will now proceed to describe by way of example the mode of manu-
facturing the tribasic phosphate of ammonia (3AzH*OPhO³) conform-
ably to this improved method as follows:-I take a certain quantity
of sulphuric acid properly diluted, into which I throw little by little, and
with stirring the phosphates to be decomposed in the pulverulent state
(phosphorites, coprolytes, bone, earth, animal charcoal, and such like
ingredients), and after sufficiently stirring and mixing, I decant the
liquor. This liquor I concentrate, and after bringing it to a required
degree of concentration, I throw in a certain quantity of lime or
carbonate of lime so as to completely convert all or nearly all the free
phosphoric acid contained in it into acid phosphate of lime; I then
treat this liquor either hot or cold with sulphate of ammonia, whereby I
effect the double decomposition herein-before alluded to, that is to say,
I produce in the liquor a certain amount of acid phosphate of ammonia
and a precipitate of sulphate of lime which I afterwards separate by any
of the well known means.
I obtain a liquor containing acid phosphate of ammonia mixed with
impurities resulting from the reaction of the sulphuric acid and
sulphates, and also natural impurities such as iron, soluble silicia, and
alumine, which have to be.climinated, but the greater part of the lime is
got rid of. To effect this and above all to get rid of the sulphuric acid,
I treat the above-mentioned liquor with phosphate of baryta, lead, or
strontiane which forms a corresponding insoluble sulphate, or I form the
said phosphates in the liquor by adding thereto oxides of barium, lead,
or strontium, or their carbonates, or other salts of barium, lead, or
strontium capable of producing phosphates of the same which are
decomposable by sulphate of ammonia. I separate this precipitate, and
then in order to remove the other impurities I neutralize by ammonia,
and thus separate them in the state of precipitate. The liquor is then.
formed solely of neutral phosphate of ammonia. I now either pass a
current of ammoniacal gas or add liquid ammonia to produce the tribasic
phosphate (3AzH¹ОPhО³).
The residue from neutralization of the above acid liquor serves to
produce phosphate of soda or potash by operating thereon as follows:-
I boil the residue with an excess of soda, potash, or carbonates of these
bases or corresponding sulphurets, or again with other salts of the above
bases capable of producing the desired decomposition such as silicates
and borates. I thus produce insoluble residues of iron, alumina, and

page_text: phosphate of soda or potash which may be rendered soluble at the
expense of the phosphoric acid contained in the precipitate.
The soluble phosphates formed by the above means may be separated
by filtration or otherwise and be purified by crystallization.
Having now described the nature of this Invention for "Improve-
ments and Modifications in the Treatment of Phosphate in General, and
in the Production and Purification of Phosphoric Acid and its Combi-
nations," and the means by which it may be carried into practical effect,
I would remark in conclusion that I hereby declare this Invention to
consist in, and I claim, the production of soluble acid phosphates by
attacking earthy phosphates especially phosphate of lime with properly
diluted sulphuric acid, also the subsequent precipitation of the earthy
matter by means of alkaline sulphates, as for instance by sulphate of
ammonia and the extraction of the sulphuric acid contained in the
residual liquor by treatment thereof with the phosphate of baryta, lead,
or strontia, or the carbonates or other suitable salts of these bases as
above described.
I also claim the manner above described of treating the residues
obtained by neutralization of the acid liquor by means of carbonates,
sulphurets, silicates, borates, or other salts capable of forming insoluble
residues with the iron and alumina of these precipitates, and of pro-
ducing at the same time soluble phosphates by double decomposition as
above stated.
In witness whereof T the soid Alexander Runwne hare
above stated.
In witness whereof, I, the said Alexander Browne, have hereunto
set my hand and seal, this Tenth day of January, in the year of
our Lord One thousand eight hundred and seventy-three.