IMPROVEMENTS IN OBTAINING SULPHUROUS ACID
Year: 1865

page_text: LETTERS PATENT to Astley Paston Price, of 47, Lincoln's Inn Fields,
in the County of Middlesex, Consulting Chemist, for the Invention of
"IMPROVEMENTS IN OBTAINING SULPHUROUS ACID."
PROVISIONAL SPECIFICATION left by the said Astley Paston Price
at the Office of the Commissioners of Patents. with his Petition, on the
15th March 1865..
I, ASTLEY PASTON PRICE. of 47. Lincoln's Inn Fields, in the County of
Middlesex Consulting Chemist, do hereby declare the nature of my said
Invention for "IMPROVEMENTS IN OBTAINING SULPHUROUS ACID," to be as
follows:-
My Invention relates to the obtaining the sulphurous acid contained in the
mixed gases which are evolved during and result from the combustion or
oxidation at a high temperature of sulphur or of ores or compounds con-
taining sulphur. or from the combustion of sulphureted compounds, and consists
[Price 8d.1

page_text: in effecting the solution, or absorption, and separation of the sulphurous
acid gas by means of water, which may be brought into contact with the mixed
gases either by the employment of what is known as a scrubber, or by the
employment of any suitable gas-impregnating apparatus. or instead of em-
ploying water only to effect the solution or absorption of the sulphurous acid
gas, I employ either a solution in water of a suitable sulphite, such as sulphite
of soda, or I employ water containing in suspension an insoluble or sparingly
soluble sulphite, which is rendered soluble by the absorption of an additional
quantity of sulphurous acid forming a bisulphite or higher sulphite.
Having obtained a solution of the sulphurous acid I effect the entire or
partial expulsion of the same from the solution by elevating the temperature
of the solution contained in a closed vessel, and provided with inlet and outlet
pipes, either by the application of heat internally or externally, or by the
injection of steam inio or through the solution of sulphurous acid or of the
higher sulphites, or by subjecting such solutions to the action of a vacuum
either with or without the application of heat.
The sulphurous acid gas resulting may either be employed direct for the
production of sulphuric acid, or for other useful purposes in the arts, or it
may be collected in suitable reservoirs or gasometers, and may then be
employed for the production of sulphuric acid in the leaden chambers, as
is well understood; or it may be employed for other useful purposes in
the arts.
SPECIFICATION in pursuance of the conditions of the Letters Patent, filed
by the said Astley Paston Price in the Great Seal Patent Office on
the 15th September 1865.
TO ALL TO WHOM THESE PRESENTS SHALL COME, 1. ASTLEY
PASTON PRICE, of 47, Lincoln's Inn Fields. in the County of Middlesex.
Consulting Chemist; send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria. by Her Letters
Patent, bearing date the Fifteenth day of March, in the year of our Lord
One thousand eight hundred and sixty-five, in the twenty-eighth year of
Her reign, did, for Herself, Her heirs and successors, given and grant unto
me. the said Astley Paston Price. Her special license that I, the said
Astley Paston Price. my executors, administrators, and assigns, or such
others as I, the said Astley Paston Price. my executors, administrators,

page_text: 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 "IMPROVEMENTS IN OBTAINING SULPHUROUS ACID," upon the
condition (amonst others) that I. the said Astley Paston Price, 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 YB, that I. the said Astley Paston Price, do hereby
declare the nature of my 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:-
My said Invention relates to the obtaining the sulphurous acid contained in
the mixed gases which are evolved during and result from the combustion or
oxidation at a high temperature of sulphur, or of ores or compounds containing
sulphur, or from the combustion of sulphuretted compounds. In the pro-
duction of sulphurous acid, either by the burning or oxidation of sulphur or of
metallic sulphurets, or from the combustion of sulphuretted compounds, either
by the admission of or in the presence of atmospheric air. the resulting
sulphurous acid gas is always diluted and mixed with impurities, such, for
example. as nitrogen and atmospheric air: and when evolved from calcining
or smelting furnaces, in addition to other and the before-mentioned diluents,
the mixed gases will contain carbonic acid. In some cases such dilution may
not prevent its employment, but it often happens that the sulphurous acid gas
produced from certain reactions in the arts is rendered so dilute or may
contain such impurities as to be of little or no value either for the production
of sulphuric acid therefrom or for other purposes. Now my Invention has
for its object the separation of sulphurous acid from such or similar diluents,
and to obtain the same in a purer and more concentrated state.
-
The Invention is based on the solubility of sulphurous acid in water or in
water containing in solution or in suspension certain sulphites, and upon the
entire or partial expulsion or separation of the sulphurous acid so absorbed
either by the elevation of the temperature of such solutions, or by the
employment of a vacuum, the solution being at an elevated or at the ordinary
temperature.

page_text: In carrying on my invention contince the mxGH GRAD
means of a fan, or by means of suction and forcing pumps.. or other apparatus.
and bring the same in contact with water. or with water containing in solution
soluble sulphites, or insoluble or difficultly soluble sulphites in suspension.
either in what is known as a scrubber. or in a modification of the same, or by
means of a gas-impregnating apparatus: and I effect the absorption or solution
of the sulphurous acid, whilst the gases which are not absorbed or retained in
solution are allowed to escape.
Having obtained a solution of the sulphurous acid gas. and in order to.
effect the entire or partial expulsion or separation of the gas therefrom.
I either submit the same. contained in a closed vessel provided with exit and
inlet pipes, to the action of heat, either by the injection of steam into the
solution, or by the application of heat to the solution, or I submit the solution
contained in a vessel, such, for example, as a vacuum tube or boiler. or in
any suitable vessel or apparatus arranged so that a vacuum or partial vacuum
may be obtained therein, as is well understood, to diminished pressure or to
what is known as the action of a vacuum either at the ordinary or at an
elevated temperature, and the sulphurous acid gas thus liberated is conducted
by means of pipes either directly to the leaden chambers for the production of
sulphuric acid, or to a gasometer or reservoir: or it may be employed for
other useful purposes.
Various modifications in the apparatus and arrangements for effecting the
absorption of the sulphurous acid gas, and also for effecting the expulsion of
the same, may be used, but I wish it to be understood that I make no claim
to the apparatus employed. It will be found that the liberation of the
sulphurous acid gas from its solution in water will be more easily effected in
vacuo than from the solutions of the sulphites.. and for that reason I more
particularly prefer when employing these to apply heat in conjunction with
the employment of a vacuum.
Having now described and particularly ascertained the nature of my 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 obtaining sulphurous acid from
mixed gases, and the separation and utilization of the same by effecting the
absorption or solution of sulphurous acid in water or in a solution of sulphites,
or in water holding in suspension sulphites capable of absorbing the sulphurous
acid gas, and of disengaging the same when the temperature of the solution

page_text: is elevated, or when subjected to the action of a vacuum, either at the ordinary
or at elevated temperatures.
In witness whereof. 1. the said Astley Paston Price, have hereunto set
my hand and seal. the Twelfth day of September, One thousand eight
hundred and sixty-five.
ASTLEY PASTON PRICE. (L.B.)