IMPROVEMENTS IN THE PRODUCTION OF CAUSTIC ALKALIES AND OF CARBONIC ACID
Year: 1874

page_text: LETTERS PATENT to John Henry Johnson, of 47, Lincoln's Inu
Fields, in the County of Middlesex, Gentleman, for the Invention
of "IMPROVEMENTS IN THE PRODUCTION OF CAUSTIC ALKALIES AND OF
CARBONIC ACID."-A communication from abroad by Charles Juron,
. Antoine Imbert, Joannes Juron, and Louis Imbert, all'of Paris, in
the Republic of France.
Scaled the 30th October 1874, and dated the 11th May 1874.
PROVISIONAL SPECIFICATION left by the said John Henry Johnson
at the Office of the Commissioners of Patents, with his Petition, on
the 11th May 1874.
I, JOHN HENRY JOHNSON, of 47, Lincoln's Inn Fields, in the County.
of Middlesex, Gentleman, do hereby declare the nature of the said
Invention for "IMPROVEMENTS IN THE PRODUCTION OF CAUSTIC ALKALIES AND OF.
CARBONIC ACID," a communication to me from abroad by Charles Juron,
Antoine Imbert, Joannes Juron, and Louis Imbert, all of Paris, in the
Republic of France, to be as follows:-
This Invention relates to the conversion on a commercial scale of:
alkaline carbonates into caustic alkalies by a dry method; and to the
}

page_text: production of carbonic acid, and consists in introducing steam at a
suitable pressure into a furnace or tube in which it is superheated, and
then causing such superheated steam to pass through or to come in
contact with the mass of carbonate to be converted, such carbonate
being placed in its ordinary condition in a receptacle composed of copper
or aluminous clay. The superheated steam will gradually elevate the
temperature of the carbonate to the degree at which it decomposes;
carbonic acid is evolved, and the alkaline oxide is obtained at a degree of
purity varying with the nature of the substance treated and the conduct
of the operation.
The apparatus which it is proposed to employ in carrying out this
Invention consist of a steam generator, of a gas generator, also a
Siemens' gas regenerative furnace, and of a receptacle of similar form to
those used in metallurgy, into which receptacle the substance in its
natural condition is successively charged for conversion into a caustic
alkali.
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 9th November 1874.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, John
HENRY JOHNSON, of 47, Lincoln's Inn Fields, in the County of Middlesex,
Gentleman, send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her
Letters Patent, bearing date the Eleventh day of May, in the year
of our Lord One thousand eight hundred and seventy-four, in the
37th 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, admini-
strators, 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 "IM-

page_text: PROVEMENTS IN THE PRODUCTION OF CAUSTIC ALKALIES AND OF CARBONIC ACID," a
communication to me from abroad by Charles Juron, Antoine. Imbert,
Joannes Juron, and Louis Imbert, all of Paris, in the Republic 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 seal, 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 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 Iuvention relates to the conversion on a commercial scale of
alkaline carbonates into caustic alkalies by the employment of a dry
method, and to the production therefrom of carbonic acid, and consists
in introducing steam at a suitable pressure into a furnace or tube in
which the steam is superheated, and then causing such superheated
steam to pass through or to come in contact with the mass of carbonate
to be converted, such carbonate being placed in its ordinary condition in
a closed or open receptacle composed of copper, aluminous clay, or other
suitable material. The superheated steam will gradually elevate the
temperature of the carbonate to the degree at which decomposition can
be effected; carbonic acid is then evolved, and the alkaline oxide is
obtained in the receptacle at a degree of purity varying with the nature
of the substance treated, and the manner in which the operation has
been conducted.

page_text: It is obvious however that the form and construction of the apparatus
employed in carrying out this Invention may be varied as found.
requisite.
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 herein-before in part recited Letters Patent is, the simul-
taneous production of a caustic alkali and of carbonic acid from alkaline
carbonates, in the manner herein-before described.
In witness whereof, I, the said John Henry Johnson, have to this
my Specification set my hand and seal, the Ninth day of
November One thousand eight hundred and seventy-four.
J HENRY JOHNSON 11.01
J HENRY JOHNSON (L.S.)