IMPROVE- MENTS IN THE SEPARATION OF SULPHURETTED HYDROGEN FROM NITROGEN
Year: 1885

page_text: from Nitrogen.
We EDWARD WILLIAM PARNELL of 4 Clayton Square Liverpool in the County
of Lancaster Analytical Chemist and JAMES SIMPSON of the same place, Alkali
Manufacturer, do hereby declare the nature of our said invention for "IMPROVE-
MENTS IN THE SEPARATION OF SULPHURETTED HYDROGEN FROM NITROGEN
to be
as follows:
It is well known that most of the schemes for the utilization of sulphuretted
hydrogen on a large scale have failed of success in consequence of the fact that
when the said gas is obtainable in quantity at a low cost it has generally been
liberated from its compounds by means of carbonic acid from a lime kiln or from
the combustion of carbonaceous matter, and is consequently so largely diluted with
nitrogen that its employment for industrial purposes is difficult and expensive.
The object of our invention is to deal with such dilute sulphuretted hydrogen
in a cheap and efficient manner so as to obtain the said gas in a pure or concentrated
form available for the convenient and economical manufacture of sulphur or its
compounds.
In carrying our invention into practice we avail ourselves of facts which have
never before had industrial application, namely that monosulphide of ammonium
at or below the ordinary temperature, say 60° Fahr or thereabouts will absorb a
considerable quantity of sulphuretted hydrogen forming sulphydrate of ammonia,
and that on heating the said sulphydrate to boiling point, or subjecting it to the
action of a partial vacuum, preferably after being slightly warmed, the sulphuretted
hydrogen will be given off in the free state, monosulphide of ammonium being
again formed in the residual solution available for repeated use.
As a convenient method of conducting the operation we bring the dilute
sulphuretted hydrogen into contact with monosulphide of ammonium by causing it
to pass through a tower filled with loose stones down which a solution of the
monosulphide is caused to flow. This treatment should be conducted at a moderate
temperature, say not above 70° Fahr. The nitrogen with which the sulphuretted
hydrogen was mixed is allowed to pass out of the tower and after washing with
an acid solution to arrest any traces of ammonia is permitted to escape into the
atmosphere, while the solution of sulphydrate of ammonia which has been formed

page_text: by the absorbtion of the sulphuretted hydrogen by the sulphide of ammonium is
drawn off and heated to boiling point in any convenient apparatus such as a steam
boiler when the sulphuretted hydrogen will pass off with the steam, from which it
can easily be separated by any simple method of condensation; or the sulphydrate
is run into a closed vessel connected with a vacuum pump by means of which the
sulphuretted hydrogen is drawn from the solution. The sulphuretted bydrogen
which is obtained from the sulphydrate of ammonium is passed through a wash
tower containing an acid solution to arrest any trace of ammonia, and conducted to
a gasometer or other convenient receptacle for use as may be required. The
monosulphide of ammonium which remains behind can be used repeatedly for
absorbing further quantities of sulphuretted hydrogen, but in the course of time it
may bave absorbed carbonic.acid to such an extent as to render it advisable to
treat it with an acid such as vitriol for the production of an ammonia salt, or other
use in the arts.
When the dilute sulphuretted hydrogen which is being treated is produced from
the employment of sulphide of ammonium instead of free ammonia for the manu-
facture of alkali as described in British Patent 3815, the sulphide of ammonium
which remains after boiling off or removing by a vacuum the strong sulphuretted
hydrogen as before described, can be passed into the absorbing plant of the said
ammonia alkali process, if it be found to have absorbed any considerable quantity
of the carbonic acid with which the dilute sulphuretted hydrogen may have been
contaminated.

page_text: Improvements in the Separation of Sulphuretted Hydrogen.
from Nitrogen.
We EDWARD WILLIAM PARNELL of 4 Clayton Square Liverpool in the County
of Lancaster Analytical Chemist and JAMES SIMPSON of the same place Alkali
Manufacturer do hereby declare the nature of the said invention for "IMPROVE-
MENTS IN THE SEPARATION OF SULPHURETTED HYDROGEN FROM NITROGEN and
in what manner the same is to be performed to be particularly described and
ascertained in and by the following statement:-
"
It is well known that most of the schemes for the utilization of sulphuretted
hydrogen on a large scale have failed of success in consequence of the fact that
when the said gas is obtained in quantity at a low cost it has generally been
liberated from its compounds by means of carbonic acid from a lime kiln or from
the combustion of carbonaceous matter and is consequently so largely diluted with
nitrogen that its employment for industrial purposes is difficult and expensive.
The object of our invention is to deal with such dilute sulphuretted hydrogen
in a cheap and efficient manner so as to obtain the said gas in a pure or concentrated
form available for the convenient and economical manufacture of sulphur or its
compounds.
In carrying our invention into practice we avail ourselves of the facts which
have never before had industrial application namely that monosulphide of
ammonium at or below the ordinary temperature say 60° Fahr or thereabouts will
absorb a considerable quantity of sulphuretted hydrogen forming sulphydrate of
ammonium and that on treating the said sulphydrate to boiling point or subjecting
it to the action of a partial vacuum preferably after being slightly warmed the
sulphuretted hydrogen will be given off in the free state, mono sulphide of
ammonium being again formed in the residual solution available for repeated use.
As a convenient method of conducting the operation we bring the dilute
sulphuretted hydrogen into contact with monosulphide of ammonium by causing it
to pass through a tower filled with loose stones down which a solution of the
monosulphide is caused to flow We find in practice that a solution containing
about 5 per cent of sulphide of ammonium gives satisfactory results, but concen-
trated solutions are liable to entail a loss of ammonia This treatment should be
conducted at a moderate temperature say not above 70° Fahr The nitrogen with
which the sulphuretted hydrogen was mixed is allowed to pass out of the tower
and after washing with an acid solution to arrest any traces of ammonia is
permitted to escape into the atmosphere, while the solution of sulphydrate of
ammonium which has been formed by the absorption of the sulphuretted hydrogen
by the sulphide of ammonium is drawn off and heated to boiling point in any
convenient apparatus such as a steam boiler when the sulphuretted hydrogen will
pass off with the steam from which it can easily be separated by any simple
method of condensation or the sulphydrate is run into a closed vessel connected.
with a vacuum pump by mears of which the sulphuretted hydrogen is drawn from

page_text: the solution The sulphuretted hydrogen which is obtained from the sulphydrato
of ammonium is passed through a condensing apparatus so constructed that the
condensed steam which will contain some sulphide of ammonium will flow back
again into the boiler and is then passed through a wash tower containing an acid
solution to arrest any traces of ammonia and conducted to a gasometer or other
convenient receptacle for use as may be required-Water taps should be placed in
suitable position for washing back any crystals of sulphide of ammonium that may
accumulate in the pipes-The monosulphide of ammonium which remains behind
can after cooling be used repeatedly for absorbing further quantities of sulphuretted
hydrogen, but in the course of time it may have absorbed carbonic acid or oxygen
to such an extent as to render it advisable to treat it with an acid such as vitriol,
for the production of an ammonia salt, or other use in the arts, or if the impurity
consists chiefly of carbonate it may again be converted into sulphide by the
addition of sulphide of calcium preferably in solution.
When the dilute sulpheretted hydrogen which is being treated is produced from
the employment of sulphide of ammonium instead of free ammonia for the
manufacture of alkali as described in B. P. 38185 the sulphide of ammonium which
remains after boiling off or removing by a vacuum the strong sulphuretted hydrogen
as before described, can be passed into the absorbing plant of the said ammonia
alkali process; if it be found to have absorbed any considerable quantity of
the carbonic acid with which the dilute sulphuretted hydrogen may have been
contaminated.
In order that the method of carrying our improvements into effect may be
clearly understood we have appended hereto a sheet of drawings a is a chamber
with a perforated bottom 6 which forms the cover of a tower c The said tower c
is made at the bottom with a tank d and is divided into two parts vertically by
the partition e. The tower above the tank is filled with coke or other suitable
material a grid being preferably provided for the said coke to rest on finlet way.
g outlet leading to the washing tower h, having on top an acid tank i with
perforated bottom bj outlet, e partition-From the tank d at the bottom of the
tower ca pipe k leads to the pump 1, from which a pipe m leads to the bottom of
the decomposing tower n-Within the tower n is a steam coil 0, p pipe from the
tower n to the cooler p¹ and from the cooler p¹ to the chamber a-q way from the
tower n into the pipe r which opens at one end into the chamber a, and at
the other into the condenser a similar to p'; from the condenser & a pipe t leads to
the tower and acid tank u similar to h, v outlet, w pump connected to the tanks
of the towers hu; x discharge pipe of the pump-y refrigerating coil in a.
Mixed nitrogen and sulphuretted hydrogen enter the tower a by the way ƒ and
passes down through the coke at one side of the partition e and up through the
coke at the other side of the partition to the outlet pipe g; during this course the
mixed gases come in contract with solution of monosulphide of ammonia which
is flowing through the perforated bottom of the chamber a, the monosulphide
absorbs the sulphuretted hydrogen, and carries it into the tank d. The nitrogen
passes away through the tower h where it comes in contact with diluto acid
Howing through the perforated bottom of the tank i the acid absorbs any ammonia
carried over by the nitrogen and carries it into the tank d-The nitrogen passes
away by the pipe j. The sulphydrate of ammonia in the tank d of the tower a is
pumped into the tower n where it is heated by the steam coil o until it parts with
the sulphuretted hydrogen which passes through the condensers to the wash
tower u where any ammonia is separated by the acid and carried into the tank a².
The purified sulphuretted hydrogen passing away by the pipe v to a gasometer.or
other receptacle. The water condensed in s flows down the pipe r mainly into a
where it meets with the monosulphide of ammonia solution which has flowed from
the tower n through the cooler p' into the chamber a. The refrigerating coil y
completing the cooling of the liquid which flows down the tower c as above set
forth. The acid in the tanks di d² is pumped by the pump w back into the
tank i i

page_text: Having now particularly described and ascertained the nature of our said
invention and in what manner the same is to be performed we declare that what
we claim is
First. The above described process for separating sulphuretted bydrogen from
nitrogen consisting in the absorption of the said sulphuretted hydrogen by a
solution of monosulphide of ammonium forming sulphydrate of ainmonium and
the subsequent treatment of the said sulphydrate of ammonium with heat or with
a partial vacuum whereby strong sulphuretted hydrogen is given off, and mono-
sulphide of ammonium is again produced available for repeated use.
Second. Treating the nitrogen which has been separated from the sulphuretted
hydrogen in the manner described with an acid solution before allowing it to
escape for the purpose set forth.
Third. Treating the strong sulphuretted hydrogen obtained as above described.
with an acid solution in the manner and for the purpose set forth.
J. T. KING,
Per W. J. Johnson,
Agent.