IMPROVEMENTS IN THE MANUFACTURE OF MURIATIC AND SULPHURIC ACIDS
Year: 1854

page_text: LETTERS PATENT to William Hähner, of Leghorn, for the Invention of
"IMPROVEMENTS IN THE MANUFACTURE OF MURIATIC AND SULPHURIC ACIDS."
A communication.
Sealed the 29th August 1854, and dated the 28th March 1854.
PROVISIONAL SPECIFICATION. left by the said William Hähner at
the Office of the Commissioners of Patents, with his Petition, on the
28th March 1854.
I, WILLIAM HÄHNER, of Leghorn, do hereby declare the nature of the said
Invention for "IMPROVEMENTS IN THE MANUFACTURE OF MURIATIC AND SULPHURIC
ACIDS" to be as follows:-
This method is based on the property which chlorine' possesses of acting as a
powerful oxydizing agent; thus sulphurous acid in contact with moist chlorine
becomes transformed immediately into sulphuric acid, while the chlorine passes
into hydro-chloric acid. The vapours of hydro-chloric acid which proceed
from the furnace are caused to pass over peroxide of manganese to convert
them into chlorine, which is more promptly and completely effected if the
vapours are mixed with the vapour of water. The vapours are then caused
to pass into chambers suitably constructed of proper materials, into which
also are introduced vapours of sulphurous acid which are developed in a

page_text: separate furnace, either by the combustion of sulphur or by the roasting of.
pyrites or other metallic sulphurets. These vapours immediately combine
together, and produce hydro-chloric and sulphuric acids. When the chlorine
is not sufficiently moist it is necessary to introduce into the chamber the
vapour of water. To avoid all loss of acid the vapours which issue from
the chamber are caused to pass up one or several cylinders or chimneys, full
of coke or pumice stone or other material moistened with water.
draft of the furnaces for the development of sulphurous acid it is easy to
regulate the proportion of the two gases (chlorine and sulphurous acid) which
is necessary to the complete transformation into sulphuric and hydro-chloric
acids.
By the
In the manufacture of sulphuric acid according to the known methods a
mixed system of nitric acid and chlorine may be employed with advantage, the
formation is then very rapid, and there is a great economy of nitric acid.
The sulphuric acid obtained by this method is always mixed with hydro-
chloric acid, from which, however, it is very easily separated by distillation.
When it is wished to employ sulphuric acid for the manufacture of soda it
is not necessary to separate the hydro-chloric acid.
SPECIFICATION in pursuance of the conditions of the Letters Patent, filed
by the said William Hähner in the Great Seal Patent Office on the
18th September 1854.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, WILLIAM
HÄHNER, of Leghorn, send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her Letters
Patent, bearing date the Twenty-eighth day of March, in the year of our Lord
One thousand eight hundred and fifty-four, in the seventeenth year of Her
reign, did, for Herself, Her heirs and successors, give and grant unto me, the
said William Hähner, Her special licence that I, the said William. Hähner,
my executors, administrators, and assigns, or such others as I,. the said.
William Hähner, my executors, administrators, and assigns, should at any
time agree with, and no others, from time to time and at all times there-
after during the term therein expressed, should and lawfully might make, use,
exercise, and vend, within the United Kingdom of Great Britain and Ire-
land, the Channel Islands, and Isle of Man, an Invention for "IMPROVEMENTS
IN THE MANUFACTURE OF MURIATIC AND SULPHURIC ACIDS," a communication, upon
the condition (amongst others) that I, the said William Hähner; by an instru-

page_text: ment 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 William Hähner, do hereby declare
the nature of the 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 thereof (that is to say):-
This method is based on the property which chlorine possesses of acting as
a powerful oxydizing agent; thus sulphurous acid in contact with moist chlorine
becomes transformed immediately into sulphuric acid while the chlorine passes
into hydro-chloric acid. The vapours of hydro-chloric acid which proceed from
the furnace are caused to pass over peroxide of manganese to convert them
into chlorine, which is more promptly and completely effected if the vapours
are mixed with the vapour of water. The vapours are then caused to pass
into chambers suitably constructed of proper materials, into which also are
introduced vapours of sulphurous acid which are developed in a separate
furnace, either by the combustion of sulphur or by the roasting of pyrites or
other metallic sulphurets. These vapours immediately combine together and
produce hydro-chloric and sulphuric acids. When the chlorine is not suffi-
ciently moist it is necessary to introduce into the chamber the vapour of
water. To avoid all loss of acid the vapours which issue from the chamber
are caused to pass up one or several cylinders or chimneys, full of coke or
pumice stone or other material moistened with water. By the draft of the
furnaces for the developement of sulphurous acid it is easy to regulate the
proportion of the two gases (chlorine and sulphurous acid) which is necessary
to the complete transformation into sulphuric and hydro-chloric acids.
In the manufacture of sulphuric acid according to the known methods
a mixed system of nitric acid and chlorine may be employed with advan-
tage, the formation is then very rapid, and there is a great economy of nitric
acid. The sulphuric acid obtained by this method is always mixed with
hydro-chloric acid, from which, however, it is very easily separated by
distillation.
When it is wished to employ sulphuric acid for the manufacture of soda it
is not necessary to separate the hydro-chloric acid.
And in order that my said Invention may be most fully understood, and
readily carried into effect, I will proceed to describe the Drawing hereunto
annexed.

page_text: •
Figure 1 shows a longitudinal section of the apparatus, which I prefer to
employ when manufacturing sulphuric and muriatic acids by means of the
vapours generated in the manufacture of soda. A is a passage proceeding
from a soda furnace; B is a steam jet which supplies moisture to the vapours,
which then pass into the passage C, of which a plan in section is shown at
Figure 2; D, D, are screens in this chamber which cause the vapours to pass
in a circuitous course; E, E, are openings by which peroxide of manganese is
introduced into and spread over the bottom of this passage. The vapours
after passing over the oxide of manganese, by which they are wholly or in
part converted into chlorine, enter the chamber F, into which are also
introduced by the pipe G-fumes from burning sulphur, and it is the com-
bustion of this sulphur to supply these fumes which evaporates the water
in the boiler H, from which the steam is derived for the jet B. The
gases introduced by the passages C and G act on each other in the chamber
F, so as to produce sulphuric and muriatic acids, which partly run to the
bottom of the chamber F, from whence they are conveyed by the tube I to
the chamber K, and which partly pass in the form of vapour by the passage
L into the chamber K, where a further portion is condensed, and may be
drawn off by the cock M. The vapour still uncondensed passes by the passage
N into the vessel O, which contains pieces of coke supported on bars. This
coke is kept constantly moistened by water proceeding from the cistern P,
and the water is distributed over the coke by the apparatus Q, consisting of a
double trough turning on, a centre, and which inclines from side to side by the
weight of the water. . The acid vapours in passing up amongst this coke are
almost completely absorbed by the moisture which runs to the bottom of the
chamber O, and from thence to the chamber K. Such portions of the vapour
as are not condensed escape by the chimney R, and to this point the workman
should direct particular attention, as, if chlorine escapes, it shows that the
quantity of sulphurous acid supplied to the chamber F is deficient; and if, on
the contrary, sulphurous acid. escape, it indicates that that gas is supplied in
excess. to the chamber F. The mixed acids which are drawn off at M may
be separated by distillation, and afterwards the sulphuric acid may be con-
centrated in the ordinary manner. Figure 3 shows a longitudinal section of
part of a similar apparatus, arranged for the manufacture of acid from the
sulphurous acid obtained by calcining ores. S is a passage by which the
sulphurous acid is conveyed from the calcining furnace to the chamber T
which corresponds with the chamber F (Figure 1); U is an apparatus of the

page_text: ordinary description for the manufacture of chloride. The gases mix as before
in the chamber T, they then pass together by the passage V, in which is the
steam jet W, to supply moisture to the gases, into the chamber X, which
corresponds with the chamber K (Figure 1), and the rest of the apparatus
is precisely similar to that shown in Figure 1. I would here remark that
in manufacturing sulphuric acid by the ordinary process chlorine may be
introduced with advantage into the chamber, by which a great saving of nitre
is effected, and the action takes place with great rapidity, but when chlorine
is thus introduced into the chamber the acids, if required separate, must be
distilled.
Having thus described the nature of my Invention, and the manner of
performing the same, I would have it understood that I do not confine myself
to the exact details described; but what I claim is, the manufacture of sulphuric
and muriatic acids by the action of chlorine (obtained when manufacturing
sulphate of soda or otherwise) on sulphurous acid in suitable chambers,
(whether such sulphurous acid be obtained by the combustion of sulphur, or by
the roasting of ores,) as described.
In witness whereof, I, the said William Hähner, have hereunto set my
hand and seal, this Nineteenth day of August, in the year of our Lord
One thousand eight hundred and fifty-four.
WILLIAM HAHNEK. (L.S.)