Year: 1888

page_text: Date of Application, 1st Feb.. 1888
Complete Specification Left, 31st Oct., 1888
Complete Specification Accepted, 14th Dec., 1888
We ALEXANDER MACOMB CHANCE and JAMES FREDERICK CHANCE of Oldbury in
the county of Worcester Alkali Manufacturers, do hereby declare the nature of this
invention to be as follows:-
--
If sulphide of sodium or potassium obtained by known or other means is dissolved
in or mixed with water and treated by gases containing carbonic acid, decomposition
occurs with the formation of carbonate of the base and sulphuretted hydrogen, which
latter however, as obtained by the processes hitherto proposed is diluted with such
large and variable quantities of other gases that it cannot be easily turned to
account.
By the present invention the sulphuretted hydrogen is obtained accompanied by
a much smaller and more constant quantity of other gases so that it may be burned
directly in the air for the manufacture of sulphurous and sulphuric acids or be
profitably treated for the production of sulphur or for other purposes.
In carrying our invention into effect we introduce the sulphide dissolved in or mixed
with water into a series of vessels connected by pipes and furnished with inlet and
outlet ways as hereinafter setforth, and we pump or pass through some or all of such
vessels. gases containing carbonic acid. We prefer to use the gases evolved from a
closed lime kiln such gases consisting almost entirely of carbonic acid and nitrogen.
The first action of the carbonic acid is to decompose the sulphide with evolution of
sulphuretted hydrogen, and this sulphuretted hydrogen is driven forward and meets
with further quantities of sulphide, is absorbed with production of sulphydrate so that
at first the gases issuing from the last vessel contain little or no sulphuretted hydrogen
and may be delivered into the atmosphere either directly, or through puritiers to free
Before the issuing gases
them from any sulphuretted hydrogen they may contain.
begin to contain sulphuretted hydrogen in appreciable quantity, we close the outlet
from the last vessel and open that from some one of the intermediate vessels where we

page_text: find that the issuing gases contain a large proportion of sulphuretted hydrogen because
the carbonic acid is now acting on the sulphydrate formed as aforesaid, and for each
equivalent of carbonic acid absorbed, two equivalents of sulphuretted hydrogen are
being evolved.
We therefore conduct away these gases so long as they contain
sulphuretted hydrogen in sufficient quantity preferably into a gasholder and apply
them to any of the above mentioned purposes..
When the quantity of sulphuretted hydrogen becomes too small we close this outlet,
and having emptied the first vessel or vessels and filled another or others later in the
series with a fresh mixture of sulphide and water we resume our operations, as at first
and so proceed continuously.
The apparatus which we employ consists of a series of vessels furnished with pipes
and connections so that they may be worked in series each vessel being capable of
being made the first intermediate and last of the series substantially as setforth in our
complete specification No. 8666 of the year 1887.
The carbonates of soda or potash formed by the decomposition respectively of the
sulphides of sodium or potassium will be in solution in the carbonated liquors removed
from the process, or partly dissolved in and partly mixed with them, the latter
especially being the case when bicarbonate of soda which is not very soluble in water
has been formed. These liquors or mixtures may be treated for the production of
alkali or other wise utilized.
If the sulphides used are not pure, but mixed with other substances, the treatment
of the carbonated liquors and solid residues will be modified in accordance with their
composition. Thus if in the place of sulphide of sodium there be used the substances
produced in the Le Blanc process of making soda commonly known as Black Ash, the
carbonated residue will consist mainly of a mixture of carbonates of soda and lime, the
former partly in solution in the liquor.. And similarly with the analogous substance
produced in the manufacture of potash by the Le Blanc process.
If it is desired to prevent the formation of bicarbonate of soda, the liquors may be
heated by any convenient means, as by steam, or by previously heating the gases
containing carbonic acid or otherwise.
Dated this 31st day of January 1888.

page_text: COMPLETE SPECIFICATION.
Improvements in Treating Sulphides of Sodium and Potassium to
Obtain Sulphuretted Hydrogen and in Apparatus Employed
therein.
We ALEXANDER MACOMB CHANCE and JAMES FREDERICK CHANCE of Oldbury in
the County of Worcester, Alkali Manufacturers, do hereby declare the nature of this
invention and in what manner the same is to be performed, to be particularly described
and ascertained in and by the following statement :-
If sulphide of sodium or of potassium obtained by known or other means is dissolved
in or mixed with water and treated by gases containing carbonic acid, decomposition
occurs with the formation of carbonate or carbonates of the base and sulphuretted
hydrogen, which latter however as obtained by the processes hitherto proposed is
diluted with such large and variable quantities of other gases that it cannot be easily
turned to account.
By the present invention the sulphuretted hydrogen is obtained accompanied by
a much smaller and more constant quantity of other gases so that it may be burned
directly in air for the manufacture of sulphurous and sulphuric acids, or be profitably
treated for the production of sulphur, or for other purposes.
In carrying our invention into effect we introduce the sulphide dissolved in or mixed
with water into a series of vessels connected by pipes and furnished with inlet and
outlet ways as hereinafter setforth and we pump or pass through some or all of such
vessels gases containing carbonic acid. We prefer to use the gases evolved from a
The first
closed limekiln consisting almost entirely of carbonic acid and nitrogen.
action of the carbonic acid is to decompose the sulphide with evolution of sulphuretted
bydrogen, and this sulphuretied hydrogen is driven forward and meeting with further
quantities of sulphide is absorbed with production of sulphydrate so that at first the
gases issuing from the last vessel contain little or no sulphuretted hydrogen and may
be delivered into the atmosphere either directly or through purifiers to free them from
any sulphuretted hydrogen they may contain. Before the issuing gases begin to con-
tain sulphuretted hydrogen in appreciable quantity we close the outlet from the last
vessel and open that from some one of the intermediate vessels where we find that the
issuing gases contain a large proportion of sulphuretted hydrogen because the carbonic
acid is now acting on the sulphydrate formed as aforesaid and for each equivalent of
carbonic acid absorbed two equivalents of sulphuretted hydrogen are being evolved. We
therefore conduct away separately these gases so long as they contain sulphuretted
hydrogen in sufficient quantity preferably into a gasholder, and apply them to any
of the above mentioned purposes. When the quantity of sulphuretted hydrogen
becomes too small we close this outlet and having emptied the first vessel or vessels
and filled another or others later in the series with a fresh solution or mixture
of sulphide and water we resume our operations as at first and so proceed
continuously.

page_text: ·
During the process, if the liquors be kept cold, there will be formed some bicar-
bonate or other carbonate of the base containing more than one equivalent of carbonic
acid, and in the second part of the process this will be prejudicial in some measure
to obtaining gases sufficiently rich in sulphuretted hydrogen, on account of the
increased quantity of carbonic acid absorbed. To prevent such formation in great
measure and to decompose any such compound that may have already been formed,
the liquors may during the second part of the process be heated by any convenient
means.
The apparatus which we employ consists of a series of vessels furnished with pipes
and connections substantially as shewn in the accompanying drawings.
Figure 1 is a longitudinal elevation part being in section and Figure 2 a plan of
one modification of apparatus under our invention. a are seven tall cylindrical vessels
such as we prefer to use and are marked 1. to 7. are false bottoms perforated with
small holes, c manholes and lids for allowing access to the interior of the vessels, d taps
or valves above and e taps or valves below the perforated bottoms b, for the purpose of
running off the contents of the vessels a, the taps or valves e being used only when it
is necessary to empty the space below the perforated bottoms, carbonic acid gas
supply main descending pipes leading from the supply main f to the vessels a
beneath the perforated bottoms b, the pipes g being fitted at the bends with pieces g¹
having covers, or with hooded bends, to allow of the use of rods to clear away any
stoppage in the said pipes g. These rods may be and preferably are fixed to work
through stuffing boxes, h connecting main, i return main, pipes leading from the
connecting and return mains , i, to the descending pipes, pipes leading from the
tops of the vessels a to the said connecting and return mains, taps or valves on branch
pipes from the gas supply main for opening and closing communication between the
said main and the descending pipes g, m n taps or valves in the pipes & between the
vessels a and the connecting main h, and between the connecting main and return
main respectively, o. p. taps or valves in the pipes between the descending pipes g
and connecting main and between the connecting main and return main i respec-
tively, 4 taps or valves between the pipes and in the mains and i respectively.
s exit main connected to the tops of the vessels a through pipes t, taps or valves on
the pipes t, for opening and closing communication between the exit main and the
vessels a. tap or valve for opening and closing communication between the exit
main's and the gasholder or store for, sulphuretted hydrogen.or place where the same
is to be used. w tap or valve between the exit main s and the atmosphere. By another
arrangement the exit mains may be closed at one end, and be at the other end divided
into two branches, one leading to the atmosphere and the other to the gas holder or
place where the sulphuretted hydrogen is to be stored or used, each branch being
Furnished with a tap or valve. All the taps enumerated except d. e should always be
either fully opened or fully closed, since if only partly opened they are liable to become
worn by the action or friction of the gases. We do not therefore use any of these taps
to govern the flow of gases, but we put for this purpose one or more other taps which
we call check taps, and which are not shewn in the appended drawings on the main s.
Although these check taps become worn the other taps will always close tightly and
prevent leakage. c is a conduit for the sulphide solution or mixture. y are pipes con-
necting the conduit a with the tops of the vessels a. taps or valves in the pipes y.
In place of the false bottoms 7 distributing roses or other arrangements may be
employed.
=
Each vessel is further furnished with a pipe not shewn in the accompanying drawings,
for the admittance of steam preferably near the bottom of the vessel for warming the
liquor. Such steam must be delivered at such a pressure as to secure its entrance into
the vessel.
In treating sulphide of sodium or of potassium under our invention in the apparatus
herein described the number of vessels used for one cycle of operations-will depend-in
a great measure on their size and construction, and on the power of the pump aspirator
or other agent by which the gases are to be forced or drawn through the series of
vessels. But it will not be convenient to employ fewer than three vessels for one cycle

page_text: of operations, as we require a last vessel from which the first gases are delivered into
the atmosphere, an intermediate vessel from which the strong gases are taken for
storage or use, and a first vessel the contents of which shall during the time that the
two kinds of gases are passing away have become carbonated.
In describing as follows our method of procedure we assume the employment of
five vessels in one cycle of operations. These vessels, say numbers 1. to 5. as on the
appended drawings are filled to the required height, say about two thirds full, with
sulphide solution or mixture through the conduit, pipes y and taps. Communication
is then shut off between the vessels a and the conduit, and the tap 2 between the gas
main fand the descending pipe leading to the first vessel, in this case No. 1 is opened
so as to allow the gases to enter the said vessel. Such taps my. and o are opened as will
allow the gases passing off from the first vessel to flow by the pipes k, main h and
pipes and g to the second vessel of the series and so on to the last vessel, in this case
No. 5. From this last vessel the gases pass by a pipe and tap u to the exit main s,
and thence by the tap wc to the atmosphere.
After a time it is found that gases may be obtained from one of the vessels probably
in this case No. 3 containing sufficient sulphuretted hydrogen to render them of use.
The tap m therefore between the third and fourth vessels, and the tap u between the
fifth vessel and the exit main, and the tap w in the exit main are closed, whilst the
tap in the pipe t leading from the third vessel to the exit main, and the tap v on
that end or branch of the exit main which leads to the gas holder or place where the
sulphuretted hydrogen is to be used are opened. During this part of the operation
steam may be admitted to warm the liquors in the vessels now in use, and in order to
condense any steam that may be carried over with the gases apparatus for that purpose
is provided between the tap and the gas holder.
Whilst the strong gas is passing away through the tap to be utilized other empty
vessels of the series in this case say Nos. 6 and 7 are filled with the sulphide solution
or mixture. When the gas issuing past the tape becomes too dilute for use, the
steam having been shut off, the said tap and the tap u between the third vessel and
the exit main are closed, and the tap between the first vessel of the series and the
gas main and the tapo between the second and third vessels are also closed. The
tap between the gas main and the third vessel, and also the several taps m
governing communication between the third and remaining vessels are opened. The
tap between the last vessel, in this case now number 7, and the exit main, and the
tap in the exit main are also opened.
The contents of vessels Nos. 1 and 2 which should now have been carbonated are
blown or drawn out through the taps d. If it is found that the contents of only one of
these vessels have been sufficiently carbonated only that one of them is emptied, the
other being connected to the gas main so as to become the first of the series, instead
of the third vessel being so connected as above setforth.
If it is desired that a vessel or vessels in the direct order of the series should be
omitted say No. 3 in the series 2. 3. 4. 5. 6. 7. the tap o between the second and third
vessels and the tap m between the third and fourth vessels are closed, and the taps
between vessels Nos. 2 and 4 opened. When the series is so used that gases have to
travel from one vessel to another in the opposite direction to the series, that is to say
from a vessel later to a vessel carlier in the series, such taps mnr po are opened as
will allow the gases to flow from such later vessel through the return main to the
descending pipe g leading into the earlier vessel.
It will be obvious that by the proper opening and closing of taps or valves any
number of vessels may be used in series, and that any of the said vessels may be made
in turn the first, intermediate or last of the series, and that any vessel or vessels may
be passed over. It will further be obvious that the vessels may be worked as two
series.
The carbonated solutions or mixtures resulting from the process may be treated for
the production of alkali or otherwise utilized.
If the sulphides used are not pure, but mixed with other substances the treatment
of the carbonated liquors and solid residues will be modified in accordance with their

page_text: composition. Thus if in the place of sulphide of sodium there be used the substance
produced in the Le Blanc process of making soda commonly known as Black Ash the
carbonated residue will consist mainly of a mixture of carbonates of Soda and Lime,
the former partly in solution in the liquor and similarly with the analagous substance
produced in the manufacture of potash by the Le Blanc process.
Having now particularly described and ascertained the nature of our said inven-
tion and in what manner the same is to be performed we would point out that
we do not confine ourselves to every detail of apparatus, for example a vessel or vessels
could be divided into compartments and used in the place of a series of vessels, but
what we claim is :-
First. Treating sulphides of sodium and potassium to obtain sulphuretted hydrogen
substantially in the manner herein described.
Second. In obtaining sulphuretted hydrogen from sulphides of sodium and potassium
separating from the sulphuretted hydrogen a large portion of the other gases sub-
stantially in the manner described.
Third. Apparatus to obtain from sulphides of sodium and potassium sulphuretted
hydrogen separated from a large portion of the other gases, such apparatus consisting
of vessels and mains in combination with pipes taps valves and connections and also
pumps, or aspirators all substantially as setforth.