IMPROVEMENTS IN THE MANUFACTURE OF WHITE LEAD, AND IN THE PURIFICATION OF CARBONIC ACID GAS USED IN THE SAID MANUFACTURE, AND IN APPARATUS THEREFOR
Year: 1873

page_text: LETTERS PATENT to George Haseltine, of the "International Patent
Office," Southampton Buildings, London, Doctor of Laws, for the
Invention of "IMPROVEMENTS IN THE MANUFACTURE OF WHITE LEAD, AND
IN THE PURIFICATION OF CARBONIC ACID GAS USED IN THE SAID MANUFACTURE,
AND IN APPARATUS THEREFOR."-A communication from abroad by
Asa P. Meylert, of New Britain, Connecticut, United States of
America.
COMPLETE SPECIFICATION filed by the said George Haseltine at
the Office of the Commissioners of Patents, with his Petition and
Declaration, on the 18th January 1873, pursuant to the 9th
Section of the Patent Law Amendment Act, 1852.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, GEORGE
HASELTINE, of the "International Patent Office," Southampton Buildings,
London, Doctor of Laws, send greeting.
WHEREAS I am in possession of an Invention for "IMPROVEMENTS

page_text: ACID GAS USED IN THE SAID MANUFACTURE, AND IN APPARATUS THEREFOK,
ΑΠΩ
have petitioned Her Majesty to grant unto me, my executors, admini-
strators, and assigns, Her Royal Letters Patent for the same, and have
made solemn Declaration that it has been communicated to me from
abroad by Asa P. Meylert, of New Britain, Connecticut, United States
of America.
NOW KNOW YE, that I, the said George Haseltine, do hereby
declare that the following Complete Specification, under my hand and
eal, fully describes and ascertains the nature of the said Invention, and
in what manner the same is to be performed, in and by the following
statement, reference being had to the accompanying Drawing forming
a part of this Specification :-
My Invention relates to the manufacture of white lead by means of
improved apparatus, and also to improved methods of purifying the
carbonic acid gas used in the said manufacture.
I will first proceed to describe the improved apparatus used for the
manufacture of white lead. The nature of this portion of the said
Invention consists in an apparatus whereby the carbonic acid gas
required for corroding the lead is used to assist in conveying the vapor
of acetic acid into contact with the metallic lead, and is also used
to assist in vaporizing the acetic acid required for corrosion.
The method of manufacturing white lead by the said apparatus is as
follows-Thin strips or pieces of lead of any convenient size are placed
in a suitable chamber or house. At any convenient distance from this
chamber, and connected thereto by a pipe or pipes, or within the
chamber itself, is placed a vessel, reservoir, or receptacle of any suitable
form or shape containing acetic acid of any suitable strength. Carbonic
acid gas either pure or mixed with oxygen or with common air is forced
through a suitable pipe or pipes into the said receptacle containing acetic
acid, the gas being passed through or over the acid, and then passed from
the said receptacle freely into the room containing metallic lead for
corrosion. Steam is likewise introduced at any convenient point, and
mingled with the gas and vapor.
The Drawing represents a sectional view of the said apparatus.

page_text: acid gas; C is a purifying reservoir containing materials for purifying
carbonic acid gas; D is an exhaust force pump or blower; E is a tank
containing water for gas purification; F is a steam boiler; G is a
chimney; h is a sand bath; i is a sand pedestal; v, w, x, y, and z are
pipes for conveying gases and vapors; a, b, and n are valves or gates in
the pipes; c is a gate or slide in the chimney; d'is an opening for the
gas pipe in chimney; e is a flue from the boiler; f is a water pipe to
supply the tank E; g is a steam pipe opening to pipe z and room A.
Any other suitable apparatus may also be used for this purpose; other
suitable acid, as for example, nitric acid may be substituted for acetic
acid.
The carbonic acid gas may be obtained from the combustion of fuel
from the decomposition of any of the carbonates or from any other
source.
I will now proceed to describe the aforesaid improved methods of
purifying carbonic acid gas. Carbonic acid gas when obtained from the
combustion of coal, coke, or other fuel, is usually purified by washing
the gases with water. This, however, must be used in large quantities
in order to remove ordinary impurities, thus conveying away much of the
carbonic acid gas in solution, and at best leaving impurities sufficient to
render the gas unfit for use in the manufacture of fine carbonates, as
for example, in the manufacture of white lead.
A jet of steam admitted into contact with the gaseous products of
combustion purifies these gases more perfectly and more economically
than washing the same with water and the alkaline and earthy car-
bonates, and particularly the bicarbonate of soda will effect the puri-
fication of the carbonic acid gas which is present in the gaseous products
of combustion by removing impurities usually present, and which are
also injurious in the application of these gaseous products to the manu-
facture of white lead and of other carbonates. The nature of this part
of the said Invention consists in diffusing steam with the gaseous
products of combustion and also in bringing them into contact with
an alkaline or earthy carbonate in order to effect a purification of the
carbonic acid gas contained in such products of combustion.
My mode of operation is as follows:-The gaseous products of com-
bustion are exhausted or forced by a pump or blower through a pipe
" exhaust is
or reservoir. into which a jet of steam either "live" or
"

page_text: admitted. They are then passed through or in contact with a solution
or mixture of carbonate of soda in water.
The apparatus used for this purpose is an ordinary tank or cask closed
and made air-tight, and having an entrance and an exit pipe for the
gases. The former pipe is made to dip beneath the surface of the water
which contains the purifying materials in the bottom of the tank, the
latter pipe being inserted near the top of the tank to convey away the
gases which have been forced through the purifying mixture. This
apparatus is shewn in the accompanying Drawing at C in connection
with the aforesaid apparatus for manufacturing white lead. Other
suitable apparatus may however be used for this purpose. While any.
alkaline or earthy carbonate may be used in solution or suspended
in a suitable liquid or in a wet mass for this purpose a soluble car-
bonate obviously possesses advantages over those which are insoluble
in water, and of the latter the carbonates of soda are preferable to
any others, and the bicarbonate of soda is preferable to all others.
Moreover the ordinary oxides, such as soda for example, may be advan-
tageously used instead of the carbonates. It has been found by ex-
perience that when the oxide or the ordinary carbonate of soda, or any
mixture of them is used, the result is the union of a portion of the
carbonic acid gas with this base, and the formation of the bicarbonate
of soda or of other highly carbonated compounds of soda which are
gradually decomposed by the sulphur compounds contained in the
gaseous products of combustion, thus setting free the carbonic acid gas
which was at first absorbed, and which entered into combination with
the soda, the final result being the same as regards the purification of
the gas as when bicarbonate. of soda is introduced at first.
Where steam cannot be readily obtained the carbonic acid gas may
be purified in the ordinary way by washing the products of combustion
with water, and then exposing them to the influence of an alkaline or
earthy carbonate in the manner herein-before mentioned.
I also make use of another method of purifying carbonic acid gas, of
which the following is a description :—
This process
is based chiefly upon the affinity which the deutoxide
of lead has for the sulphur compounds which constitute the principal
impurities in carbonic acid gas obtained as above described, that is to

page_text: say, from the combustion of coal, coke, or other fuel; it consists in
passing the gas as it comes from the furnace or generator through or
over a mixture consisting of deutoxide of lead held in suspension in
water or other liquid, whereby these impurities are removed. The
apparatus used for this process is similar to that herein-before described
for the purification of carbonic acid gas, or the purifying materials can
be placed in the purifying reservoir C as shown in the accompanying
Drawing in the apparatus for manufacturing white lead.
Having thus fully described the said Invention as communicated to
me by my foreign correspondent, and the manner of performing the
same, I wish it understood that I claim,-
First. The combination of the pipe y conveying carbonic acid gas and -
terminating in the receptacle B, the acid receptacle B, the corroding
chamber A and their connections, substantially as and for the purpose
set forth.
Second. The combination of the purifier C, the acetic acid receptacle B,
the corroding chamber A and their connections, substantially as and for
the purpose set forth.
Third. The combination of the pump exhauster or blower D, the acid
receptacle B, the corroding chamber A and their connections, substan-
tially as and for the purpose set forth.
Fourth. The combination of the pump or blower D, the purifier C,
the acid receptacle B, the corroding chamber A and their connections,
substantially as and for the purpose set forth.
Fifth. The combination of the furnace for generating the carbonic acid
gas, the washer E, the acid receptacle B, the corroding chamber A and
their connections, substantially as and for the purpose set forth.
Sixth. The combination of the furnace for generating the carbonic
acid gas, the washer E, the pump or blower D, the acid receptacle B,
the corroding chamber A and their connections, substantially as and for
the purpose set forth.
Seventh. The combination of the furnace for generating the carbonic
acid gas, the washer E, the pump or blower D, the purifier C, the acid
receptacle B, the corroding chamber A and their connections, arranged
substantially as and for the purpose set forth.

page_text: Eighth. The method of purifying carbonic acid gas by diffusing steam_
therewith, as above described.
Ninth. The method of purifying carbonic acid gas by bringing the
same into contact with an alkaline or earthy carbonate as above
described.
Tenth. The method of purifying carbonic acid gas by diffusing steam
therewith, and then bringing the same into contact with an alkaline or
earthy carbonate, as above described.
Eleventh. The method of purifying carbonic acid gas by the use of
deutoxide of lead, as above described.
In witness whereof, I, the said George Haseltine, have hereunto
set my band and seal, this Seventeenth day of January, in the
year of our Lord One thousand eight hundred and seventy-three.
Witness,
W. ROB. LAKE,
8, Southampton Buildings,
London.
GEORGE HASELTINE. (L.S.)