PROVEMENTS IN THE MANUFACTURE OF SULPHURIC ACID, AND IN APPARATUS FOR THE SAME
Year: 1863

page_text: PROVEMENTS IN THE MANUFACTURE OF SULPHURIC ACID, AND IN APPARATUS
FOR THE SAME."-A communication from abroad by Louis Désiré Verstraet,
Chemist, and Charles Schmid, Merchant, both of 29, Boulevart St.
Martin, Paris.
Sealed the 21st August 1863, and dated the 4th March 1863.
PROVISIONAL SPECIFICATION left by the said William Clark at the
Office of the Commissioners of Patents, with his Petition, on the
4th March 1863.
I, WILLIAM CLARK, of 53, Chancery Lane, in the County of Middlesex,
Engineer and Patent Agent, do hereby declare the nature of the said Inven-
tion for "IMPROVEMENTS IN THE MANUFACTURE OF SULPHURIC ACID, AND IN
APPARATUS FOR THE SAME," to be as follows:-
The manufacture of sulphuric acid has hitherto necessitated the employment
of leaden chambers, the construction of which is enormously expensive, and
can only be met by large capital; it is for this reason that the manufacture on
a small scale has hitherto failed. Besides the expense of the materials
themselves the construction of these chambers requires a large plant and
buildings of considerable area.
According to this Iuvention I dispense entirely with the use of leaden
vessels in the manufacture of sulphuric acid, which may thus be readily made
even by those who are not manufacturers, but still use large quantities of this
acid, and thus obtain it at less cost. Although I dispense with lead chambers
the improved apparatus of this Invention nevertheless presents a large surface

page_text: to the gas, and so permit of its action on one and the other with the same
facility as with lead chambers.
The improvements are based on the principle that a combination of gas or
vapours may be easily effected under the influence and through the inter-
mediation of porous bodies. The substance I employ for multiplying the
points of contact of the gas, and presenting a large surface by its porosity in
a small volume, consists of coke which is well washed and calcined, the
apparatus being formed of stoneware and of peculiar form. The production of
sulphuric acid is effected in the ordinary manner, that is to say, by the
combustion either of sulphur or of iron or copper pyrites. This combustion
is effected in the furnaces A, A¹, seen in plan in the annexed Drawing, and,
as well known in such manufacture, the azotate of soda is decomposed in
said furnaces by means of sulphuric acid in order to produce azotic acid,
necessary for the transformation of sulphurous acid into sulphuric acid. On
leaving furnaces A, A', the sulphurous acid vapour and the azotic acid pass
throug sheet-iron pipes B, B₁, into the central brick chimney D, and
thence throug the large cast-iron pipe E into a large leaden pipe F, dipping
into a bath filled with water for cooling the gas. On its exit from tube F
the gas passes through the long bent pipe G, G, having at its lower part H
a cock O for drawing off the condensed liquids. The part H which is much
larger than G dips in a bath N filled with water, and also intended to cool
the gas and retain any dust and arsenious and selenious acids ordinarily
contained in pyrites. In order to prevent the dust and acids produced by the
combustion of the pyrites from being drawn into the other parts of the
apparatus, I apply at bottom of G in part H a small leaden trap X, which
projects below the bottom of bath N, and by which all the impurities may be
easily removed as they are deposited thereon; on leaving part H the gases pass
into a stone pipe I in communication with a chamber J three-fourths filled
with coke. The lower series of chambers are each furnished with cocks P, P,
through which the condensed sulphuric acid passes into the leaden baths S, S.
In order to give greater density to the acid in bath S, I raise it by means of
air or steam pressure into baths T, T, through which, by means of cocks a, the
acid produced in the last series of apparatus passes into another series nearer
the furnaces, and so on until it arrives at the first series, where it requires a
high degree of concentration; and in order to facilitate the action of the gas
I also inject a jet of steam into the chamber by means of cocks R, R. On
leaving the last row of chambers the gases which are entirely deprived of
sulphurous and nitrous acids, and containing only inert gases, are passed out
at the chimney.

page_text: The Invention thus consists in the application for the manufacture of
sulphuric acid of the chemical principle of using porous bodies to facilitate
the combination of the gases and vapours, as also in the general arrangement
of apparatus represented in the accompanying Drawing, and the peculiar form
given to the tube G for concentrating the arsenious and selenious acids and
collecting dust which may be contained, together with the application of
stoneware chambers superposed as described, or other apparatus serving the
same purpose, whatever its form and arrangement; and lastly in the use of
coke or other porous bodies as and for the purpose described.
SPECIFICATION in pursuance of the conditions of the Letters Patent filed
by the said William Clark in the Great Seal Patent Office on the
2nd September 1863.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, WILLIAM
CLARK, of 53, Chancery Lane, in the County of Middlesex, Engineer and
Patent Agent, send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her Letters
Patent, bearing date the Fourth day of March, in the year of our Lord
One thousand eight hundred and sixty-three, in the twenty-third year of
Her reign, did, for Herself, Her heirs and successors, give and grant unto
me, the said William Clark, Her special licence that I, the said William
Clark, my executors, administrators, and assigns, or such others as I, the
said William Clark, 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 THE MANUFACTURE OF SULPHURIC ACID, AND IN APPARATUS FOR THE SAME,"
a com" to me from abroad by Louis Désiré Verstraet, Chemist, and
Charles Schmid, Merchant, both of 29, Boulevart St. Martin, Paris, upon
the condition (amongst others) that I, the said William Clark, my executors
or administrators, by an instrument in writing under my, or their, or one
of their hands and seals, 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.
"

page_text: NOW KNOW YE, that I, the said William Clark, do hereby declare the
nature of my said Invention, and in what manner the same is to be per-
formed, to be particularly described and ascertained in and by the following
statement, reference being had to the Sheet of Drawings hereunto annexed,
and to the letters and figures marked thereon (that is to say):-
The manufacture of sulphuric acid has hitherto necissitated the employment
of leaden chambers, the construction of which is enormously expensive, and
can only be met by large capital; it is for this reason that the manufacture
on a small scale has hitherto failed. Besides the expense of the materials
themselves the construction of these chambers requires a large plant and
buildings of considerable area.
According to this Invention I dispense entirely with the use of leaden vessels
in the manufacture of sulphuric acid, which may thus be readily made even
by those who are not manufacturers, but still use large quantities of this acid,
and thus obtain it at less cost. Although I dispense with lead chambers, the
improved apparatus of this Invention nevertheless presents a large surface
to the gas, and so permit of its action on one and the other with the same
facility as with lead chambers.
These improvements are based on the principle that the combination of
gases or vapors may be easily effected under the influence and through the
intermediation of porous bodies. The substance I employ for multiplying
the points of contact of the gas, and presenting a large surface by its porosity
in a small volume, consists of coke which is well washed and calcined, the
apparatus being formed of earthenware and of peculiar form. The production
of the sulphuric acid is effected in the ordinary manner, that is to say, by the
combustion either of sulphur or of iron or copper pyrites. This combustion is
effected in the furnaces A, A', seen in plan in the annexed Drawing, and as
well known in such manufacture the azotate of soda is decomposed in said
furnaces by means of sulphuric acid in order to produce azotic acid, necessary
for the transformation of sulphurous acid into sulphuric acid. On leaving
furnaces A, A', the sulphurous acid vapour and the azotic acid pass through
sheet-iron pipes B, B³, into the central brick chimney D, and thence through
the large cast-iron pipe E into a large leaden pipe F dipping into a bath filled
with water for cooling the gas. On its exit from tube F, the gases pass
through the long bent pipe G, G, having at its lower part H a cock O for
drawing off the condensed liquids. The part H, which is much larger than G,
dips in a bath N filled with water, and also intended to cool the gas and retain
any dust and arsenious and selenious acids ordinarily contained in pyrites.
In order to prevent the dust and acids produced by the combustion of the

page_text: pyrites from being drawn into the other parts of the apparatus, I apply at
bottom of tube G in part H a small leaden trap X, which projects below the
bottom of bath N, and by which all the impurities may be easily removed as
they are deposited thereon; on leaving part H the gases pass into a stone
pipe I in communication with a chamber J three-fourths filled with coke.
The vapors thence pass in the direction of the arrows through four or five
series of chambers all filled with coke. The lower series of chambers are
each furnished with cocks P, P, through which the condensed sulphuric acid
passes into the leaden baths S, S. In order to give greater density to the
acid in baths S, I raise it by means of air or steam pressure into baths T, T,
through which, by means of cocks a, the acid produced in the last series of
apparatus passes into another series, nearer the furnaces, and so on until it
arrives at the first series, where it acquires a high degree of concentration, and
in order to facilitate the action of the gas I also inject a jet of steam into the
chambers by means of cocks R, R. On leaving the last row of chambers the
gases, which are entirely deprived of sulphurous and nitrous acids, and con-
taining none but inert gases, are passed out at the chimney.
Having described the nature of this Invention, and the manner of performing
the same, I declare that what I claim as the Invention to be protected by the
herein-before in part recited Letters Patent is, the application in the manu-
facture of sulphuric acid of the chemical principle of using porous bodies to
facilitate the combination of the gases and vapors, as also in the general
arrangement of apparatus represented in the accompanying Drawing, and the
peculiar form given to tube G, for condensing the arsenious and selenious
acids and collecting dust which may be contained, together with the application
of stoneware chambers superposed as described, or other apparatus serving the
same purpose, whatever its form and arrangement; and, lastly, in the use of
coke or other porous bodies as and for the purpose described.
In witness whereof, I, the said William Clark, have hereunto set my
hand and seal, this First day of September, in the year of our Lord
One thousand eight hundred and sixty-three.
Witness,
W. G. E. SWINNOCK,
53, Chancery Lane,
London.
W. CLARK. (L.S.)