IMPROVEMENTS IN THE PREPARATION OF SOLUBLE PHOSPHATES OF LIME
Year: 1870

page_text: LETTERS PATENT to John Henry Johnson, of 47, Lincoln's Inn
Fields, in the County of Middlesex, Gentleman, for the Invention
of "IMPROVEMENTS IN THE PREPARATION OF SOLUBLE PHOSPHATES OF LIME."
Sealed the 6th September 1870, and dated the 31st March 1870.
PROVISIONAL SPECIFICATION left by the said John Henry Johnson at
the Office of the Commissioners of Patents, with his Petition, on the
31st March 1870.
I, JOHN HENRY JOHNSON, of 17, Lincoln's Inn Fields, in the County
of Middlesex, Gentleman, do hereby declare the nature of the said
Invention for "IMPROVEMENTS IN THE PREPARATION OF SOLUBLE PHOSPHATES Or
LIME," a communication to me from abroad by Ernest Deligny, of Paris,
in the Empire of France, to be as follows:-
This Invention relates to the production of what may be termed a
sesqui-basic phosphate of lime, which product is obtained from bones,
mineral phosphates, or other phosphatic sources, and which is soluble in
water, or in water containing carbonic acid, and it consists, firstly, in

page_text: submitting trebasic phosphate of lime, either natural or artificially
prepared, to the action of acid phosphate of lime, whereby a sesqui-basic
phosphate of lime is obtained; second, in submitting to the action of
heat either that product, which is obtained in effecting the decomposition
of bones, coprolites, or other phosphate of lime by means of hydrochloric
acid, or a mixture of a solution of chloride of calcium and of acid
phosphate of lime, whereby the chloride of calcium is in part decomposed
and a sesqui-basic phosphate of lime formed. The solid sesqui-basic
phosphate of lime thus obtained is to be separated from the salts of lime
contained in the supernatant solution, and after having been washed and
dried may be employed for such purposes as the acid phosphate of lime
is now used, or for other applications.
SPECIFICATION in pursuance of the conditions of the Letters Patent,
filed by the said John Henry Johnson in the Great Seal Patent
Office on the 30th September 1870.
"
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, JOHN
HENRY JOHNSON, of 47, Lincoln's Inn Fields, in the County of Mid-
dlesex, Gentleman, send grecting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her
Letters Patent, bearing date the Thirty-first day of March, in the
year of our Lord One thousand eight hundred and seventy, in the
thirty-third year of Her reign, did, for Herself, Her heirs and successors,
give and grant unto me, the said John Henry Johnson, Her special
license that I, the said John Henry Johnson, my executors, adminis-
trators, and assigns, or such others as I, the said John Henry Johnson,
my executors, administrators, or 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 PREPARATION OF SOLUBLE PHOSPHATES OF LIME," a communication to
me from abroad by Ernest Deligny, of Paris, in the Empire of France,
upon the condition (amongst others) that I, the said John Henry
Johnson, my executors or administrators, by an instrument in writing
under my hand and scal, should particularly describe and ascertain the

page_text: 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 John Henry Johnson, 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, that is to say :-
The said Invention relates to the production of what may be termed
sesqui-basic phosphate of lime, which product is obtained from bones,
mineral phosphates, or other phosphatic sources, and which is soluble in
water, or in water containing carbonic acid, and it consists, first, in
submitting trebasic phosphate of lime, either natural or artificially
prepared, to the action of acid phosphate of lime, whereby a sesqui-basic
phosphate of lime is obtained; second, in submitting to the action of
heat either that product, which is obtained in effecting the decomposition
of bones, coprolites, or other phosphate of lime by means of hydrochloric
acid, or a mixture of a solution of chloride of calcium and of acid
phosphate of lime, whereby the chloride of calcium is in part decomposed.
and a sesqui-basic phosphate of lime formed. The solid sesqui-basio
phosphate of lime thus obtained is to be separated from the salts of lime
contained in the supernatant solution, and after having been washed and
dried may be employed for such purposes as the acid phosphate of lime
is now used, or for other applications.
The reactions and operations indicated in the Specification of Letters
Patent granted to Michael Henry as a communication from Ernest
Deligny, and bearing date the Twenty-first of April One thousand eight
hundred and sixty-nine, No. 1224, are obtained in metallic vessels heated
by an open fire, and the temperature may be raised considerably above
212 degrees Fahrenheit by reason of the quantity of chloride of calcium
contained in the liquids.
In practically carrying out these operations, however, difficulties are
encountered when a liquid is heated in which a precipitate is formed.
This latter adheres to the sides of the boilers and exposes them to the
risk of being burnt. This evil is so much the more serious that it
becomes necessary to employ leaden boilers, iron being too easily attacked.
I therefore propose to apply the heat by injecting steam into the liquid
itself, which also allows of the employment of wooden vessels. It was,

page_text: however, discovered that at the boiling temperature thus produced the
reactions were modified, and that whatever was the duration of the time
of heating the crystallized precipitate obtained remained in the state
of sesqui-phosphate of lime, which may be represented by the formula
Ph O' 2 Ca O, HO+ Ph 033 Ca O, or a combination of an equivalent of
bibasic phosphate with an equivalent of tribasic phosphate, which retains
up to 260 degrees Fahrenheit an equivalent of water of combination.
This novel product is obtained in the form of a fine white brilliant
crystalline powder of great density, which is rapidly precipitated from
the liquid in which it is produced. It is washed with the greatest
facility, and is by that means completely freed from the chloride of
calcium, and it may be easily drained and dried. The resulting product
is soluble in water or in water charged with carbonic acid. The prepa-
ration of this product is effected by attacking mineral phosphates of lime
or bones with hydrochloric acid, and thus producing a concentrated
solution of soluble acid, phosphate of lime, and chloride of calcium, and
effecting the reaction by means of heat of the acid phosphate of lime
upon chloride of calcium and the precipitation of the bibasic phosphate
of lime or of the tribasic phosphate of lime, setting thereby free one half
or the whole of the hydrochloric acid employed for dissolving the phos-
phates originally operated upon. The tribasic phosphate upon being
heated by means of a jet of steam with the acid phosphate is converted
into a sesqui-basic phosphate, and a crystalline deposit is formed. The
reaction is more casily produced if the acid phosphate be in excess; or
the sesqui-basic phosphate of lime may be produced by adding lime to a
solution of the acid phosphate of lime, and thus producing tribasic phos-
phate of lime, which by reason of the presence of the acid phosphate
upon the application of heat converted into sesqui-basic phosphate of
lime. Nearly the whole of the phosphoric acid contained in the liquid
may be thus precipitated in the form of crystalline sesqui-basic phosphate.
It is advisable, however, not to precipitate the whole of the phosphoric
acid, as should iron be contained in the phosphates it would be precipi-
tated and would injure the purity of the product. As soon as the
reaction is terminated the supernatant liquid may be poured into a
separate vessel and allowed to settle, and the liquid containing the chloride
of calcium be separated (which may be applied to any of its known
uses). The precipitated phosphate is drained and washed, and finally dried
either in the open air or in a stove which is heated by utilizing waste
hent

page_text: Having now described and particularly ascertained the nature of the
said Invention, and the manner in which the same is or may be used or
carried into effect, I would observe in conclusion that what I consider to
be novel and original, and therefore claim as the Invention secured to me
by the hercin-before in part recited Letters Patent is, the converting
of tribasic phosphate of lime into acid phosphate of lime, and thus
effecting the production therefrom of sesqui-basic phosphate of lime in the
manner herein-before described.
In witness whereof, I, the said John Henry Johnson, have to this
my specification set my hand and scal, this Thirticth day of
September One thousand eight hundred and seventy.
J. HENRY JOHNSON. (L.S.)