IMPROVE- MENTS IN THE MANUFACTURE OF CHLORINE, IN TREATING SULPHUROUS ORES AND OTHER MINERALS, AND IN OBTAINING VARIOUS PRODUCTS THEREFROM
Year: 1845

page_text: TO ALL TO WHOM THESE PRESENTS SHALL COME, I, WILLIAM
LONGMAID, of the Borough of Plymouth, in the County of Devon, Gentleman,
send greeting.
WHEREAS Her present most Excellent Majesty Queen Victoria, by Her
Royal Letters Patent under the Great Seal of Great Britain, bearing date
at Westminster, the Fourth day of August, in the ninth year of Her reign,
did, for Herself, Her heirs and successors, give and grant unto me, the said
William Longmaid, my exors, adñiors, and assigns, Her especial licence, full
power, sole privilege and authority, that I, the said William Longmaid, my
exors, adiñiors, and assigns, or such others as I, the said William Longmaid,
my exors, adiñors, or assigns, should at any time agree with, and no others,
from time to time and at all times during the term of years therein expressed,
should and lawfully might make, use, exercise, and vend, within England,
Wales, and the Town of Berwick-upon-Tweed, my Invention of "IMPROVE-
MENTS IN THE MANUFACTURE OF CHLORINE, IN TREATING SULPHUROUS ORES AND
OTHER MINERALS, AND IN OBTAINING VARIOUS PRODUCTS THEREFROM;" in which said
Letters Patent is contained a proviso, that I, the said William Longmaid,
shall cause a particular description of the nature of my said Invention, and
in what manner the same is to be performed, to be inrolled in Her said
Majesty's High Court of Chancery within six calendar months next and
immediately after the date of the said in part recited Letters Patent, as in
and by the same, reference being thereunto had, will more fully and at large
appear.

page_text: NOW KNOW YE, that in compliance with the said proviso, I, the said
William Longnaid, do hereby declare that the nature of my said Invention,
and the manner in which the same is to be performed, are fully described and
ascertained in and by the following statement thereof, that is to say:-
My Invention relates to the manufacture of chlorine from iron pyrites (or
ether sulphurous ores), common salt and oxygen, and from various metallic
chlorides and oxygen. In decomposing common salt by the joint action of
iron pyretes (or other sulphurous ores), oxygen, and heat, as described in
Letters Patent granted to me, bearing date respectively the Twentieth day of
October, One thousand eight hundred and forty-two, and the Fourth day of
January, One thousand eight hundred and forty-four; the chlorine of the
salt is disengaged and combines with the metals contained in the ores forming
the chlorides of such metals; I have found by continuing the process of
calcination, as hereafter explained, the metals of certain metallic chlorides
become oxidised with evolution of chlorine. In my processes for obtaining the
chlorine thus disengaged, and rendering the same available for manufacturing
purposes, I proceed, by preference, with the mixture of ore and salt, as described
in said first former Patent, and continue the calcination in an open furnace
my
until sulphurous acid ceases to be evolved, or nearly so; I then withdraw the
charge and put it into a close furnace, with suitable apparatus attached, as here-
after described, in which I continue the calcination until chlorine ceases to be
evolved, or nearly so. The proportion in which I prefer to apply the ore to
the salt is such as shall insure the perfect decomposition of the salt, as nearly
as may be, which I find to be best accomplished by adding such quantity of
ore as shall contain about from thirty-five to forty parts of sulphur to one
hundred parts of salt. I have also discovered that various metallic chlorides,
such as those of iron, manganese, and chlorides of other metals, when heated
in contact with dry atmospheric air, are decomposed with evolution of chlorine
by the oxygen of the air combining with the metals, and forming oxides of such
metals, and which decompositions I accomplish in the same manner and by
similar apparatus to that which I employ for obtaining chlorine from the
mixture of ore and salt, as herein described. When metallic oxides, and
particularly those of manganese, copper, zinc, and lead, are mixed with hydro-
chloric acid, the residual matters contain chlorides of such metals, and I have
found that such metallic chlorides may be dried down and used for manu-
facturing chlorine by oxidising the metal of such chlorides with dry atmospheric
air, as herein described. After great labour and research, I have found that
when the metallic chlorides are decomposed by the joint action of heat and

page_text: oxygen of atmospheric air the moisture usually contained in the atmosphere
is decomposed, and the hydrogen of the water combining with a portion of the
chlorine, hydrochloric acid is formed; I therefore employ air deprived of moisture
as nearly as is practicable in the manner herein-after described, by which means
I oxidise the metals, and avoid the formation of hydrochloric acid, and chlorine
is evolved. The furnace I prefer to use is of a rectangular form, about twenty
feet long and seven feet wide in the clear, the chamber of the furnace being as
nearly as possible air-tight, having doors in the side for the purpose of charging
and stirring the charge from time to time; I conduct the flues from the fire-
place over and under the chamber of the furnace into a flue connected with a
chimney, to which flue a damper is adapted to obtain regulation of the draft.
To the furnace, the chamber of which I call the chlorine generator, I adapt a
fan, blower, or other machine for the purpose of forcing air into the chlorine
generator, which air I deprive of moisture by passing it through a chamber or
apparatus connected with the blowing machine and with the chlorine generator,
such chamber or apparatus being nearly filled with pieces of coke or other suitable
material, in which I place a layer of chloride of calcium; I force the air in at
the bottom of the chamber, having the eduction tube or flue at the top, by this
means I deprive the air of moisture, or nearly so; I then conduct the dry air
into the generator by means of tubes or flues, in order to present oxygen for
decomposing the ore and salt or metallic chlorides. When metallic chlorides
are used, I prefer to place the main tubes or flues over the top of the generator,
in order that the air passing to the generator may be heated, as I find hot air
act better than cold air; I distribute the air uniformly over the surface of the
charge in the generator by means of branch tubes, connected with the main
tubes or flues before described, such branch pipes passing through the roof into
the generator; exit tubes or flues pass from the generator, through which the
gases evolved pass into what I call a chlorine purifier, which I construct of a
flue forty feet long and one foot square, made of deal board of one inch thick,
immersed in water, which will be found to allow a portion of the water to
penetrate through so as to moisten the inner surface of the flue, and I
insert a waste pipe at the further end in order to draw off the water that has
passed into the flues, taking care that the eduction pipe be so placed as to
allow of a thin stratum of water to remain at the bottom of the wooden flues.
If immediately after putting a charge into the generator sulphurous acid gas is
found to come over, which is readily ascertained by the smell, I shut off the
communication with the purifier, and allow the vapours to pass into the chimney
till sulphurous acid gas is no longer detected, when the vapours are allowed to

page_text: pass to the purifier from the generator. For the purpose of condensing any
moisture, hydrochloric acid, metallic chlorides, or other matters that may be
accidentally evolved from the generator during the operation, I apply a lead flue
(of about nine inches diameter), at the end of the wooden flue above described,
rising to the height of ten feet, and then descending ten feet; at the lower end
it enters water in an open cistern to form a lute; the cistern also receives the
liquid or other matters that may be deposited therein; a branch flue proceeds
from the lower part of the descending lead flue into the chamber or vessel in
-which the chlorine is to be condensed or used for the ordinary purposes
of manufacture. The chlorine thus obtained is mixed with an excess of
atmospheric air, nitrogen, and other matter which do not interfere with the
combination of chlorine, with lime, or other substance used for combining with
the chlorine. I provide for the exit of such extraneous matters by applying
an eduction pipe of lead, of about two inches diameter, on the top of the chlorine
chamber, such eduction pipe rising to a height of about ten feet above the top
of the chamber. Whether I employ the mixture of partially calcined ore and
salt, or whether I use such metallic chlorides as are suitable for the purpose of
producing chlorine by the oxidation of the metals, I adopt the same means
of separating the chlorine, videlicit, by exposing such mixture of partially
calcined ore and salt, or such metallic chlorides, to the joint action of heat and
oxygen of atmospheric air deprived of moisture.
Having thus described the nature of my Invention, and the best means I am
acquainted with for performing the same, I would have it understood that I do
not confine myself to the details here given, so long as the peculiar character
of either part of the Invention be retained; but what I claim is,-
First, the manufacture of chlorine by what I call my first process, by the
calcination of a mixture of iron pyrites or other sulphurous ore and common
salt with access of atmospheric air deprived of moisture.
Second, I claim the manufacture of chlorine by what I call my second
process, by oxidising metallic chlorides, such as manganese, copper, iron, zinc,
and lead, by access of atmospheric air deprived of moisture, thereby producing
chlorine and the oxides of such metals.
In witness whereof, I, the said William Longmaid, have hereunto set my
hand and seal, this Fourth day of February, in the year of our Lord
One thousand eight hundred and forty-six.
WILLIAM (L.S.) LONGMAID.

page_text: AND BE IT REMEMBERED, that on the Fourth day of February, in the
year of our Lord 1846, the aforesaid William Longmaid came before our said
Lady the Queen in Her Chancery, and acknowledged the Specification afore-
said, and all and every thing therein contained and specified, in form above
written. And also the Specification aforesaid was stamped according to the
tenor of the Statute made for that purpose.
Enrolled the Fourth day of February, in the year of our Lord One
thousand eight hundred and forty-six.