IMPROVEMENTS IN TREATING PHOSPHATE OF LIME FOR THE MANUFACTURE OF MANURE, AND POR PURPOSES
Year: 1867

page_text: LETTERS PATENT to John Thomas Way, of Russell Road, Kensington, in
.1,
the County of Middle for the Invention of "IMPROVEMENTS IN TREATING
PHOSPHATE OF LIME FOR THE MANUFACTURE OF MANURE, AND POR
PURPOSES."
Sealed the 11th February 1868, and dated the 14th August 1867.
..
PROVISIONAL SPECIFICATION left by the said John Thomas Way at
the Office of the Commissioners of Patents, with his Petition, on the
14th August 1867.
...I, JOHN THOMAS WAY, of Russell Road, Kensington, in the County of
5 Middlesex, do hereby declare the nature of the said Invention for "IMPROVE-
✓MENTS, IN TREATING: PHOSPHATE, OF LIME FOR THE MANUFACTURE, OF MANURE, AND
FOR OTHER PURPOSES," to be as follows:
This Invention relates to the production from ordinary phosphate of lime
jand the use for manure of a compound of lime and phosphoric acid inter-
0 mediate in, composition, and, character between ordinary insoluble phosphate
11of, line and, acid or soluble phosphate of lime. By ordinary phosphate of
lime I, mean to express the phosphate of lime existing naturally in bones,
bone ash, animal charcoal, and in the usual mineral varieties of this sub-
stance, and, by acid, phosphate or soluble phosphate; of lime I mean that
15. form of readily, soluble phosphate of lime which is produced by the action of
sulphuric acid, on ordinary phosphate of lime, and which exists in the sub-

page_text: stances usually called "superphosphates." The ordinary phosphate of lime
first mentioned contains three equivalents or combining proportions of lime to
each equivalent or combining proportion of phosphoric acid, and has a per-
centage composition of lime 53-9, and phosphoric acid 46.1. I shall for the
sake of convenience call this triphosphate of lime in reference to the three
equivalents of lime it contains. The acid phosphate or soluble phosphate of lime
contains only one equvalent or combining proportion of lime to each equivalent
or combining proportion of phosphoric acid; I call this monophosphate of lime
as containing only one equivalent of lime. It has a per-centage composition
of 28 parts of lime and 72 parts of phosphoric acid. Now the compound of
lime-and-phosphoric acid which is the subject of this Invention contains two
equivalents or combining proportions of lime to one equivalent or combining
proportion of phosphoric acid, I therefore call this substance diphosphate of lime,
and it has a per-centage composition of lime 43-8 parts, and phosphoric acid
56.2 parts. This compound is known by chemists to exist, and is described in
some works on chemical science, but it has not been made for practical use,
been used or
nor by any of the methods about to be described, nor has
proposed for use as manure for which I have ascertained that it is well
suited. For whereas triphosphate of lime whether in its natural state or
artificially produced, is'. not sufficiently soluble in water for purposes of
vegetation, and the monophosphate or ordinary "superphosphate " is so readily
soluble in water that it is liable in some cases to be washed out of the soil by
heavy rain, and so cause a loss of a valuable and expensive product, the
diphosphate of lime is, soluble to the extent of from 15 to 25 grains only in a
gallon of pure water, and to a larger extent in water containing carbonic
acid; it is therefore free from both the causes of objection above referred to,
and its use for manure will be attended with great advantage, and be found
to be economical.
T
I have ascertained that diphosphate of lime can be produced with sufficient
economy to enable it to be practically used as a 'manure by the methods
which I proceed to describe:
1st. I take any form of triphosphate of lime, such as bone ash, animal
charcoal, coprolites, apatite, or phosphatic guano, and having ascertained by
analysis the proportion of carbonate and phosphate of lime in it I add to it
hydrochloric acid in such quantity as shall be sufficient to dissolve the carbo-
hate of lime, and also to unite with one-third part or one equivalent of the
--three equivalents of 'lime contained in the phosphate of lime, avoiding the use
of any considerable excess of acid beyond that mentioned above. I dilute the
acid before employing it with as much water as shall have been found by
.

page_text: previous experiments necessary to enable it to be mixed intimately with the
owdered phosphate, so that every portion may be well moistened, and in
bis-mixing I employ some suitable mechanical arrangement, such as an ordi-
nary png mill used for mixing clay. I allow the mixture to rest until I find by
treating a small portion with cold water, and testing the filtered solution by
ammonia or lime water, that very little phosphate of lime remains in solution ;
I then add cold water, and wash out the chloride of calcium which is produced
from the carbonate of lime and the 3rd part of the lime of the triphosphate.
The washed residue is the diphosphate of lime in a state more or less pure,
which I dry for use at a temperature which should not exceed 240° or 250°
Fahrenheit. Before allowing the wash water to run to waste I render.it
alkaline by lime and by subsidence or filtration. I separate and preserve the
As a source of tri-
insoluble matter which will contain phosphate of lime.
phosphate in the foregoing process I prefer to employ bone ash or .animal
charcoal, or triphosphate artificially prepared.
2nd. I treat any mineral or other phosphate with sufficient hydrochloric
acid to dissolve the triphosphate, and to the clear solution diluted with water
if necessary I add bone ash, animal charcoal, precipitated triphosphate, or
finely ground mineral phosphate (preferring the bone ash, animal charcoal, or
precipitated triphosphate) in such quantity that the triphosphate added is
equal to that in the solution; then I proceed to mix and wash as in the
previous case.
3rd. I treat substances containing triphosphate of lime with sulphuric acid
in the same manner as in making ordinary "superphosphate" of lime, and
I dissolve out in the least possible quantity of water the soluble acid mono-
phosphate produced; to this solution I add bone ash, animal charcoal, preci-
pitated triphosphate, or any mineral phosphate in fine powder (preferring the
bone asb, animal charcoal, or precipitated triphosphate) in such quantity that
I mix these materials
the triphosphate added is equal to that in the solution.
O as in the previous case, but as the mixture does not contain any chloride of
calcium it does not require washing, but after standing in the inoist state for
a sufficient time to allow of the production of the diphosphate it is dried if
necessary at a temperature of 240° or 250° Fahrenheit for use. In. some
cases I prefer to treat the phosphate of lime in the first part of this process
5 with sufficient sulphuric acid to combine with the whole of the lime and to
liberate phosphoric acid. In this case I add to the solution of this acid as much
bone ash or other substance as contains twice the phosphoric acid contained iu
the solution. In all these three methods I find that a gentle temperature given
to the mixture greatly promotes the production of diphosphate, and 1 some

page_text: times dry the mixed materials on hot plates or other convenient arrangement,
taking care that the heat does not exceed a temperature of 250° Fahrenheit.
In this case I afterwards wash the products of processes No. 1 and No. 2, but
not of No. 3 as before stated.
4th. 1 evaporate a solution of triphosphate of lime in hydrochloric acid, and
heat the residue to such temperature as shall be sufficient to enable the mono-
phosphate of lime to react upon one equivalent of the chloride of calcium
present, condensing the hydrochloric acid vapours given off. I digest the
residue with chalk or other form of carbonate of lime to decompose any mono-
phosphate of lime which may remain, and I wash the diphosphate produced to
free it from chloride of calcium, taking care to precipitate from the wash water
by lime any phosphoric acid it may contain.
5th. I find that when a solution of phosphate of lime in hydrochloric acid is
precipitated by milk of lime, or lime water, as is well known, a small part of
this precipitate may be produced in the state of diphosphate, and special pre-
cautions will be necessary, as herein-after described, to prevent the greater part
being produced in the state of ordinary triphosphate of lime.
When wishing
'to prepare the diphosphate of lime in this manner I add the lime very gradually,
and stop short in the addition of lime some time, before the liquid becomes
alkaline; or when I have added sufficient lime to render the liquid alkaline,
and to precipitate all the phosphate of lime, I run off the liquid and digest
the precipitate in a fresh and strong solution of phosphate of line in hydro-
chloric acid, or in a solution of acid phosphate or monophosphate of linie, by
which the whole or the greater part is converted into diphosphate of lime.
6th. In order to precipitate the diphosphate of lime free from triphosphate
of lime from a solution of phosphate of lime in hydrochloric acid I use car-
bonate of lime in the forin of chalk limestone, magnesian limestone, or marble,
which I digest with the solution; I find that in this case no triphosphate of
lime is produced. If an excess of chalk or other carbonate of lime has been
employed I get rid of this by digesting the diphosphate in a further quantity
of the phosphate solution. In using either of the methods described under 5
and 6 I am careful to add to the water with which I wash away the chloride of
calcium from the diphosphate sufficient lime to precipitate any phosphate it may
contain before discharging it to waste. I use the diphosphate of lime pro-
duced by either of the foregoing methods without further treatment, or after
the addition of a small quantity of sulphuric or other mineral acid as a manure,
and also employ it in the manufacture of phosphorus. I find that the
diphosphate of lime is only soluble to a limited extent in cold water. When
the water is heated the diphosphate is converted into monophosphate or acid

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent, filed
by the said John Thomas Way in the Great Seal Patent Office on the
14th February 1868.
:
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, JOHN
THOMAS WAY, of Russell Road, Kensington, in the County of Middlesex,
send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her Letters
Patent, bearing date the Fourteenth day of August, in the year of our Lord
One thousand eight hundred and sixty-seven, in the thirty-first year of Her
me,
reign, did, for Herself, Her heirs and successors, give and grant un 1 m
the said John. Thomas Way, Her special licence that 1, the said Johnomas
Way, my executors, administrators, and assigns, or such others as I, the said
John Thomas Way, 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
TREATING PHOSPHATE OF LIME FOR THE MANUFACTURE OF MANURE, AND FOR OTHER
PURPOSES," upon the condition (amongst others) that 1, the said John Thomas
Way, my executors or administrators, by an instrument in writing under my,
or their, or one of their hands and seals, should particularly describe and ascer-
tain 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 tlie said
Letters Patent.
NOW KNOW YE, that I, the said John Thomas Way, 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:-
This Invention relates to the production from ordinary phosphate of lime
and the use for manure of a compound of lime and phosphoric acil inter-
niediate in composition and character between ordinary insoluble phosphate of
lime and acid or soluble phosphate of lime. By ordinary phosphate of lime. I
mean to express the phosphate of lime existing naturally in bones, bone ash,

page_text: animal charcoal, and in the usual mineral varieties of this substance, and by acid
phosphate or soluble phosphate of lime I mean that form of readily soluble
pliosphate of lime which is produced by the action of sulphuric acid on ordinary
phosphate of lime, and which exists in the substances usually called "super-
phosphates." The ordinary phosphate of lime first mentioned contains three
equivalents or combining proportions of Jime to each equivalent or combining
proportion of phosphoric acid, and contains lime and phosphoric acid in the
proportion of lime 53-9, and phosphoric acid 46-1. I shall for sake of con-
venience call this triphosphate of lime in reference to the three equivalents
of lime it contains. The acid phosphate or soluble phosphate of lime contains
only one equivalent or combining proportion of lime to each equivalent or
combining proportion of phosphoric acid; I call this monophosphate of lime,
as containing only one equivalent of lime. It contains lime and phosphorie
acid in the proportion of 28 parts of lime and 72 parts of phosphoric acid.
Now the compound of lime and phosphoric acid, which is the subject of this
Invention, contains two equivalents or combining proportions. of lime to one
equivalent or combining proportion of phosphoric acid, I therefore call this
substance diphosphate of lime; and it contains lime and phosphoric acid in the
proportion of lime 43-8 parts, and phosphoric acid 56-2 parts. This compound
is known by chemists to exist, and is described in some works on chemical
science, but it lias not been made for practical use, nor by any of the methods
about to be described, nor has it been used or proposed for use as manure-for
which I have ascertained that it is well suited. For whereas -triphosphate of
line, whether in its natural state or artificially produced, is not sufficiently
soluble in water for purposes of vegetation, aud the monophosphate or ordinary
"superphosphate" is so readily soluble in water that it is liable in some cases
to be washed out of the soil by heavy rain, and so cause a loss of a valuable
and expensive product, the- diphosphate of lime is soluble to the extent of
from 15 to 25 grains only in a gallon of pure water, and to a larger extent in
water containing carbonic acid; it is therefore free from both the causes of
objection above referred to, and its use for manure will be attended with
- great ailvantage and be found to be economical.
I have ascertained that diphosphate of lime can be produced with sufficient
economy to enable it to be practically used as a manure by the methods which
I proceed to describe.
1st. I take any form of triphosphate of lime such as.. bone ash, animal
'charcoal, coprolites, apatite, or phosphatic guano, and having ascertained by
analysis the proportion of carbonate and phosphate of line in it I add to i
bydrochloric acid-in such quantity as-shall be sufficient to dissolve the car-

page_text: bonate of lime and also to unite with one-third part or one equivalent of the
three equivalents of lime contained in the phosphate.of lime, avoiding the use
of any considerable excess of acid beyond that mentioned above.. I dilute the
acid before employing it with as much water as shall have been found by
previous experiments necessary to enable it to be mixed intimately with the
powdered phosphate, so that every portion may be well moistened, and in this
mixing I employ some suitable mechanical arrangement, such as an ordinary
pug mill used for mixing clay. I allow the mixture to rest until. I find by
treating a small portion with cold water and. testing the filtered solution by
ammonia or lime water that very little phosphate of lime remains in solution:
I find that a gentle temperature given to the mixture greatly promotes the
production of diphosphate, and I sometimes dry the mixed materials on hot
plates or by other convenient arrangement, taking care that the heat does not
exceed 250° Fahrenheit; I then add cold water and wash out the chloride of
calcium, which is produced from the carbonate of lime and the part of the
lime of the triphosphate. The washed residue is the diphosphate of lime,in-a
state more or less pure, which I dry for use at a temperature which should not
exceed 240° or 250° Fahrenheit. Before allowing the wash water to run to
waste I render it alkaline by lime, and by subsidence or filtration I separate
and preserve the insoluble matter which will contain phosphate of lime. As
a source of triphosphate in the foregoing process I prefer to employ bone ash,
or animal charcoal or triphosphate artificially prepared. In carrying,,this
process into effect the proportion of bydrochloric acid to be used will depend
upon the proportions of phosphate of lime and carbonate of lime with bone
ash, animal charcoal, or other phosphoric substance or mixture of substances
employed and the strength of the bydrochloric acid itself. If liquid hydro-
chloric acid of 'sp. gr. 1.145, and containing about 30 per cent. of real acid
is used, it will require 240 parts by weight of such acid for each 100 parts of
carbonate, of lime, and 76 parts for each, 100 parts of phosphate of lime
present in the substance or mixture of substances to be acted upon, for
instance, supposing that the crude phosphate contains 70 per cent. of phosphate
of lime and 10 per cent. of carbonate of lime, the quantity of acid of 30 per
cent. to be added to each 1,000 lbs. of such crude phosphate will be 240 lbs.
for the carbonate, and 532 for the phosphate of lime, or together 772 lbs.,
and so on in relation to the varying proportions of the phosphate and carbonate
of lime in different substances treated.. As before mentioned I find that the
production of diphosphate of lime is very much assisted by the application of
a gentle heat to the mixture, but I am careful to regulate the temperature, as
otherwise the result of the action will be. to produce the ordinary triphosphate

page_text: of lime instead of the diphosphate. I have named 250° Fahrenheit as a
temperature which is both safe and sufficient for the purpose; this amount of
heat may be obtained by hot plates or ovens or other ordinary means. When
beat is to be employed an excess of hydrochloric acid may be used with
advantage, but arrangements must be made to collect and condense the fumes.
'of the excess of acid which will be driven off.
2nd. I treat any mineral or other phosphate with suflicient bydrochloric
acid to dissolve the triphosphate, and to the clear solution diluted with water
if necessary I add bone ash, animal charcoal, precipitated triphosphate or
finely ground mineral phosphate (preferring the bone asb, animal charcoal, or
'precipitated triphosphate) in such quantity that the triphosphate added is equal
-to-that in the solution, and then I proceed to mix and wash as in the previous
case. This second process is, as will be seen, a simple modification of the
process. first described, and the instructions given in respect thereto will for
the-most part-be applicable to the-second process, and are sufficient for the
carrying the said process into practical effect.
3rd. I treat substances containing triphosphate of lime with sulphuric acid
in the same manner as in making ordinary superphosphate of lime, and I
dissolve out in a small quantity of water the soluble acid monophosphate pro-
duced; to this solution I add bone ash, animal charcoal, precipitated
triphosphate, or any mineral phosphate in fine powder (preferring the bone
ash, animal charcoal, or precipitated triphosphate) in such quantity that the
ítriphosphate added is equal to that in the solution. I mix these materials
as in the previous case, but as the mixture does not contain any chloride of
calcium it does not require washing, but after standing in the moist state for
a sufficient. time. to allow of the production of the diphosphate (and as is
ascertained by testing as already explained in respect to the first process) it
is dried if necessary at a temperature of 240° or 250° Fahrenheit for use.
In some cases I prefer to treat the phosphate of lime in the first part of this
process with sufficient sulphuric acid to combine with the whole of the lime,
and to liberate phosphoric acid. In this case I add to, the solution of this acid
as much bone ash, or other substance as contains twice the phosphoric acid
contained in the solution. In making use of the method 3 the solution of
acid phosphate or of phosphoric acid produced by the action of sulphuric acid-
on phosphate of lime may if necessary be concentrated by evaporation before
mixture with the bone ash or other material. The quantity of this solution
used should be sufficient to act upon the carbonate as well as the phosphate of
lime of the bone asb, animal charcoal, or other phosphate; the heat employed
in this case may be as high as 350° without injury.

page_text: 4th. I evaporate a solution of triphosphate of lime in bydrochloric acid, and
heat the residue to such temperature as shall be sufficient to enable the
monophosphate of lime to react upon one equivalent of the chloride of calcium?
present and condensing the hydrochloric acid vapours given off: I
may digest
the residue with chalk or other form of carbonate of lime to decompose. any
monophosphate of lime which may remain, and I wash the diphosphate pro-
duced to free it from chloride of calcium, taking care to precipitate from the
wash water by lime any phosphoric acid it may contain. In carrying out this
process I dissolve the crude phosphate of lime. in hydrochloric acid diluted
with the smallest possible quantity of water so as to avoid unnecessary-
evaporation. I dry down the solution in pans or ordinary evaporating furnaces,"
taking care to arrange for the collection and condensation of the acid fumes'
which will be driven off'; the heat should not exceed 350° Fahrenheit otherwise
triphosphate of lime may be produced. The materials should be frequently
stirred, and in order to complete the decomposition the dry products after
removal from the furnaces may be powdered, mixed, and again heated. I
wash the diphosphate with or without addition of chalk according to the'
amount of acid phosphate undecomposed, and dry the diphosphate as in the
previous processes; I precipitate any phosphate in the wash water with caustic
lime.
1
5th. I find that when a solution of phosphate of lime in hydrochloric acid
is precipitated by milk of lime or lime water, as is well known, a small part of
this precipitatė may be produced in the state of diphosphate, and special pre-
cautions will be necessary, as herein-after described, to prevent the greater
part being produced in the state of ordinary triphosphate of lime. When
preparing the diphosphate of lime in this manner I add the lime very gradually
and stop short in the addition of lime some time, before the liquid becomes
alkaline, that is to say, whilst the mixture is still strongly acid with the acid
monophosphate of lime and remains.so... After continued stirring I run off
the liquor, and having washed away the chloride of calcium I dry the: residue
which is the diphosphate. I am careful to add to the liquor which is run off
and to the water with which I wash away the chloride of calcium from the
diphosphate sufficient lime to precipitate any phosphate it may contain before
discharging it to waste; or I add in the first instance sufficient lime to render
the liquid alkaline. And to precipitate all the phosphate of lime I run off the
liquid, and digest the precipitate in a fresh and strong solution of phosphate
of lime in hydrochloric acid, or in a solution of acid phosphate or mono-
phosphate of lime, by which the whole or greater part is converted into
diphosphate of lime, which I wash and dry as before.

page_text: 6th. In order to precipitate the diphosphate of lime free from triphosphate
of lime from a solution of. phosphate of lime in hydrochloric acid I use
carbonate of lime in the form of chalk limestone, magnesian limestone, or
marble which I digest with the solution, I find that in this case no tri-
phosphate of lime is produced. If an excess of chalk or other carbonate of
lime has been employed I get rid of this by digesting the diphosphate in a
further quantity of the phosphate solution.
In carrying out the method I use any ordinary vessel or tank, and I
prefer to employ chalk in very fine powder as a precipitant. I agitate the
solution of phosphate in hydrochloric acid with the chalk in vats furnished
with revolving arms or beaters, as is well known, till such time as I find by
examination of the liquid that the greater part of the phosphate is precipitated
as diphosphate, which I then wash and dry; or I mix the solution of phosphate
with chalk in a pug mill and leave the mixture at rest till the decomposition
is complete, when I wash out the chloride of calcium by cold water. If the
hydrochloric aid has been fully neutralized by phosphate of lime the quantity
of chalk to be used will be about 3rd that of the real phosphate of lime in the
solution.
It will be understood that in all cases when diphosphate is washed to
separate chloride of calcium the wash water should be precipitated with lime
to avoid loss, of phosphate. I use the diphosphate of lime produced by either
of the foregoing methods without further treatment, or after the addition of a
small quantity of sulphuric or other mineral acid as manure, and I also
employ it in the manufacture of phosphorus. I find that the diphosphate of
lime is only soluble to a limited extent in cold water; when the water is
heated the diphosphate is converted into monophosphate or acid phosphate, and
triphosphate, or insoluble phosphate, and I sometimes treat the diphosphate in
this manner for the purposes of manure or for other practical uses.
.
.In witness whereof, I, the said John Thomas Way, having hereunto set
my hand and seal, this Thirtieth day of February, in the year of our
Lord. One thousand. eight hundred and sixty-eight.
J. THOMAS WAY. (L.S.)