Improvements in the Manufacture of Peroxide of Barium and Peroxide of Hydrogen.
Year: 1891

page_text: Date of Application, 19th June, 1891
i
Complete Specification Left, 21st Mar., 1892-Accepted, 21st May, 1892
PROVISIONAL SPECIFICATION.
Improvements in the Manufacture of Peroxide of Barium and
Peroxide of Hydrogen.
1, COMTE THOMAS BROCHOCKI, of 15 Rue des Halles, Paris, in the Republic
of France, Civil Engineer, do hereby declare the nature of this invention to be as
follows:-
:-
This invention has for object to obtain anhydrous oxides of barium and peroxide
of hydrogen at less cost and in a purer state than heretofore.
To this end the process adopted according to this invention consists in the com-
bination, in a particular order and for special objects, of a series of successive
operations effected by means of a furnace and other apparatus in connection
therewith as hereinafter explained, the whole combined in such a manner as to
obtain the products in question. not only from the material in its natural state, but
also from material obtained free of cost and in the form of residue, from the
production of the peroxide of hydrogen itself and also all the residues resulting from
the successive stages or operations.
The process is effected in five successive stages by micans of the said furnace
and the apparatus in connection therewith. The furnace which is heated by gas
from a gas producing furnace has three floors and is connected with a stove. On
the middle floor are arranged three parallel vertical retorts of which the two
nearest the fireplace are of refractory material, and the other is of steel. Each
retort is closed at its ends by a bottom or register formed with numerous holes.
The lower bottom or register allows of the discharge of the calcined material into
a chamber provided with a manhole. The upper bottom or register separates the
retort from a chamber in which the material, before entering the retort, undergoes
a preliminary heating. The three upper chambers are heated by the gases of the
furnace after they have enveloped the three retorts and then the stove. Each of
the chambers is closed by means of a cover and a sand joint, and communicated by
a pipe and cocks with a corresponding gasometer.
The apparatus which serves to effect the operations comprises also a dissolving
reservoir in connection with a filter box, a precipitating tank through which the
gas taken from one of the gasometers is caused to bubble and a burner for
sulphuretted hydrogen mixed with air, the said burner being in connection with a
converting vat, provided with a discharge opening regulated by cocks, and into
which are brought the gas from the gasometer mixed with injected steam and the
sulphurous acid taken from the burner and injected by steam. Rotary pumps are
also employed to send into the lower chambers, either dried air through a purifier,
or the gas taken from a gasometer after it has passed through a purifier filled with
quicklime and caustic soda.
The first of the five stages or successive operations consists in converting sulphate
of baryta into sulphide of barium, there being obtained as a residual product,
carbonic acid or carbonic oxide which as heretofore obtained has usually been
impure. According to this invention, the calcination is effected in a closed retort,
and the gas given off is collected, and after being purified is employed as a reagent
in the other operations. For this purpose a mixture of sulphate of baryta and coal
previously united by means of petroleum tar, formed into balls and dried in the
stove, is introduced into the middle retort after being subjected to a preliminary
heating in the upper chamber. The gas given off, according as it is carbonic
acid or carbonic oxide, passes into one or other of two gasometers. When the
calcination is completed, the product is discharged into the corresponding lower
chamber where it is cooled out of contact with air, whilst a fresh operation is

page_text: commenced.
The cool sulphide is crushed, and dissolved to form a solution
having a density say of 1150. This solution is filtered, and conveyed into the
precipitating tank. The insoluble residues are added to a fresh charge to be
calcined.
The
The second operation consists in converting the sulphide of barium into
carbonate of baryta in the precipitating tank into which the carbonic acid, taken
from the gasometer, is injected by a steam jet so as to stir up the mass.
carbonic acid reacts on the sulphide, which, on becoming converted into carbonate,
thickens the liquor. The said liquor is then transferred to a filter press. whilst
the sulphuretted hydrogen, the aqueous vapour, and the surplus carbonic acid that
remain are discharged through a tube which conveys them to a burner and to a
converting vat. The carbonate of baryta obtained, as described mixed with lamp
Elack, petroleum tar or with essence of benzine, is formed into balls and dried.
From the sulphuretted hydrogen given off, the whole of the sulphur is recovered
by dividing the current of sulphuretted hydrogen into two portions one of which
passes to the burner and yields sulphurous acid which is injected by steam
into a converting vat, whilst the other portion which is similarly injected is
passed direct into the said vat where they combine with the production of sulphur
and water.
The carbonic acid required may also be obtained by the same apparatus, from
natural lime stone calcined alone in the same intermediate retort in which the
sulphate of baryta and carbon was calcined as described a partial vacuum being
produced therein by means of a fan, and a jet of superheated steam being injected
from below. The lime thus obtained serves to purify the carbonic oxide and the
air employed in the succeeding operations.
The same operation also enables sulphide of sodium to be obtained by means of
the carbonate of baryta obtained by treating the solution of sulphide of barium
with the solution of carbonate of soda. In this case however the consumption of
fuel would be increased.
The third stage or operation has for object to convert the carbonate of baryta
into anhydrous baryta. For this purpose the carbonate formed into balls with
carbonaceous matter as hereinbefore described, is charged into the first of the three
retorts wherein it is calcined after being previously heated in the upper chamber.
During this calcination the product is swept by and subjected to a current of
neutral gas previously purified, dried and heated. By this means the traces of
air, or carbonic acid are expelled. This neutral gas, for instance carbonic oxide
obtained as a secondary product of the conversion of the sulphate of baryta into
sulphide, is taken from the gasometer in which it was collected, and is passed
through a purifier containing quicklime and caustic soda. It is then conveyed
behind the gas producing furnace so as to discharge, after being heated up, under
the first retort which it traverses by passing through the holes of the registers.
This gas after heating the product contained in the upper chamber and designed
to be charged into the retort in the succeeding operation, is conducted either to a
gasometer, or to the furnace where it supports or enhances the combustion. When
the calcination is finished, the baryta is discharged into the lower chamber, whence,
after cooling, it is removed through the corresponding manhole.
The conversion of the baryta into di-oxide of barium constitutes the fourth
stage or operation and is effected in the usual manner, but in the third retort which
allows of effecting this operation under the best conditions and with the best
results. The product brought to the temperature of about 650° C. is traversed by
a current of air purified by passing it through a purifier. The oxygen of the air
combines with the baryta, and the nitrogen escapes from the upper chamber after
having there, as in the case of the preceding retorts, heated up the product which
is to be next charged into the corresponding retort. The di-oxide thus obtained is
discharged into the lower chamber where it is cooled; then it is removed and placed
in a position where it is free from the action of moisture.
The fifth and last operation relates to the production from the di-oxide of barium

page_text: of peroxide of hydrogen by utilizing the carbonic acid obtained as a bye-product in
the first operation. This operation is so much the more profitable inasmuch as the
residue obtained is pure carbonate of baryta. It is effected in a converting vat
similar to that already mentioned but with this difference that a coil arranged in
this vat, instead of being traversed by steam is traversed by cooling fluid; also
that the carbonic acid is forced by a pump and not by a steam injector; and finally
that the carbonic acid gas as it escapes from the vat is returned to the gasometer
from which it was taken.
Dated this 19th day of June 1891
COMTE THOMAS BROCHOCKI,
By L. W., per F. B.
COMPLETE SPECIFICATION.
Improvements in the Manufacture of Peroxide of Barium and
Peroxide of Hydrogen.
I, COMTE THOMAS BROCHOCK1 of 15. Rue des Halles, Paris, in the Republic
of France, Civil Engineer, do hereby declare the nature of this invention and in
what manner the same is to be performed to be particularly described and ascer-
tained in and by the following statement:-
This invention has for objects to obtain peroxide of barium and peroxide of
hydrogen or oxygenated water (hereinafter referred to as peroxide of hydrogen)
more cheaply and in greater purity than heretofore.
To this end the process
employed according to this invention consists in the combination in a definite order
and with specific objects, of a series of successive operations depending one on the
other, and carried out by means of a furnace and other suitable auxiliary apparatus
as hereinafter explained. The whole is arranged in such a manner as to allow, by
the use of the various meaus employed, and the reactions effected, of obtaining the
products in question, not only from naturally formed compounds of baryta but
also from artificially formed compounds of baryta such as sulphate or carbonate of
baryta obtained as a residue of the manufacture of peroxide of hydrogen (as
hereinafter explained) and other residual products obtained by the successive
conversions of the said material.
The process is carried out in five successive operations or stages, which are
effected in a cycle by means of apparatus the general arrangement of which is
shewn in vertical section in the accompanying drawing.
This apparatus comprises a furnace heated by the combustion of gas from a gas
generator (not shown) and in which are arranged three cylindrical retorts A B C
that communicate at their lower ends by means of movable bottoms a, with the
chambers D D'D" respectively, and at the top, by means of bottoms with the
upper retorts or chambers E E E respectively which are of iron.
The retorts A and B are of refractory material, and the retort C is of iron.
The retort A is furthermore lined with material that will not be attacked by
baryta, such for examples as magnesia, quicklime, chromate of baryta or other
analogous substance.
The upper retorts EEE" are closed by means of covers c and sand joints.
Gas escape pipes ttt" furnished with cocks S S S lead from the retorts EEE"
respectively. The bottoms a and b are each perforated with small holes so as to
allow the gases given off to pass through the chambers, and lower and upper
retorts, which, as shewn, are arranged one above another in three tiers. The
movable bottoms a and b are each operated from the outside by means of a spindle
that passes through an asbestos-packed stuffing box and is actuated by a crank
handle or the like. The lower chambers D & D receive through the pipes rr,
pure gases as hereinafter explained previously reheated in the flues of the
furnace. " are man holes adapted to be herinetically closed by suitable

page_text: The conversion of the sulphate of baryta into sulphide of barium, may also ne
effected without addition of coal, by the direct action upon sulphate of baryta BaSO.
at a white red heat in the retort B of sulphuretted hydrogen (H,S), obtained as a.
residue of the second operation hereinafter described.
By this process, which produces a sulphide of great richness, the whole of the
sulphur contained in the sulphuretted hydrogen can be obtained as free sulphur as.
shown by the following forinula :-BaSO +2 HS = BaS + SO2 + 2 H₂O + S,.
which with 2 H,S, gives BaS + 4 H₂O + 4 S.
The second operation consists in the conversion of the sulphide of barium into.
carbonate of baryta.
This is effected by the action of carbonic acid upon the solution of sulphide of
barium at a temperature of 75 to 90° C., whereby pure carbonate of baryta is.
precipitated and sulphuretted hydrogen gas is evolved as a secondary product.
according to the following formula.
1
BaSCO, H₂O = BaCO, + H₂S.
The sulphuretted hydrogen thus obtained can be advantageously used as before-
stated and as will be hereinafter further explained.
This second operation is effected in the closed vat M which is, about half filled
with the solution of barium and is heated by a steam coil.
The carbonic acid is drawn from the gas holder G' by a steam injector O and
is forced into the solution of sulphide of barium in the vat M by a pipe R which is.
perforated with small holes and is located a few centimetres above the bottom of the-
said vat. By this means the contents of the vat are constantly agitated and at the.
same time gradually heated thereby facilitating the reaction of the carbonic acid on
the sulphide, the resulting carbonate thickening the mass.
1.
The vat M is furnished with a safety valve to prevent an excessive pressure being
produced therein, and with an escape pipe designed to lead away the sulphuretted
hydrogen resulting from the reaction as well as the water vapor and the excess of,
carbonic acid.
When the reaction in the vat M is completed, which can be readily determined'
by ascertaining the nature of the escaping gases, the cock on the pipe q is closed,
and whilst continuing the injection of carbonic acid, the cock on the conduit con-
necting the vat M with a filter press, is opened. In consequence of the pressure
exerted by the gas the liquid contents of the vat together with the precipitate which
is kept in suspension by the passage of the gas through the liquid passes quickly to.
the filter wherein the carbonate of baryta is retained.
After washing with water, the pure carbonate of baryta thus obtained, is intimately
mixed with its equivalent only of carbon (lamp black, for instance) and the requisite.
quantity of tar as a binding agent. The mass thus obtained is formed into balls or
briquettes by mechanical means and suitably dried.
The sulphuretted hydrogen given off from the vat M during the above reaction
is treated for the recovery of the sulphur therein thereby preventing its escape into
the atmosphere and becoming injurious to public health. For this purpose it can be
utilized for converting the sulphate of baryta into sulphide of barium, as hereinbefore
mentioned; or it can be burnt in a closed retort within a furnace N with its equivalent.
of atmospheric air, wherely it is converted into sulphur and water according to the
following reaction:-
The sulphur vapors on passing out of the retort N are passed through a
settling box or chamber which is provided with baffle plates wherein the sulphur
is deposited.
The sulphurous vapors that escape from the box or chamber O are passed into a
receiver containing a solution of chloride of calcium by which they are converted
into a calcium compound or compounds and thus neutralized.
The reaction is complete and no trace of sulphuretted hydrogen will be found to

page_text: escape if the proportions of the sulphuretted hydrogen and air entering simultaneously
into the retort be suitably regulated by distributing cocks.
The carbonic acid necessary for precipitating the carbonate of baryta and for
the manufacture of peroxide of hydrogen may also be obtained if desired from
limestone which is calcined without addition of coal, in the retort B, in the same
manner as hereinbefore explained with reference to the calcination of the sulphate
. of baryta, excepting that a partial vacuum is first produced in the retort, by means
of an exhauster, whilst a jet of superheated steam is injected into the retort at the
.bottom.
The whole of the carbonic acid present in the limestone is thus obtained almost
instantaneously, and its separation from the water vapor is easily effected by the
condensation of this vapor.
The lime resulting from the calcination is in great part utilized in the purification
of the carbonic oxide and of the air employed in the subsequent operations. The
surplus, if any, may be sold.
If it be desired to obtain sulphide of sodium as a secondary produce, the car-
bonate of baryta can be obtained by treating the solution of sulphide of barium with
a solution of carbonate of soda, and washing in several waters the precipitated
'carbonate in order that all the soluble salts of soda shall be removed from the
precipitated carbonate. In this case however, as it is necessary to evaporate a
large quantity of water resulting from the washing operations, the consumption of
fuel and consequently the cost of the process will be increased.
The third operation consists in the conversion of the carbonate of baryta into
anhydrous baryta. I have herein before explained how the carbonate of baryta
after having been precipitated, carefully washed and admixed with its equivalent of
carbon, is formed into balls or briquettes which are suitably dried in order to expel
the last trace of water therefrom.
These balls or briquettes are charged into the retort A first passing through the
chamber or retort B which is afterward recharged with more balls or briquettes for
a subsequent operation.
The charge within the retort A is, during the entire duration of the calcination,
traversed and swept by a current of neutral gas previously purified, dried and heated.
This sweeping is effected in such a manner that the pressure in the interior of the
retort shall not increase.
By this means the traces of air which might still be present in the retort and
the carbonic acid given off as a result of the reaction, or which might have
penetrated the retort from the exterior by endosmose are expelled by the current
of neutral gas.
It
The neutral gas which may for instance be carbonic oxide a secondary product
obtained by the conversion of the sulphate of baryta into sulphide of barium, is
taken, as shewn in the drawing, by a rotary pump, from the gas holder G through
a purifier charged with pieces of quicklime and caustic soda, which remove the
carbonic acid and moisture therefrom. The purified gas is then passed through a
pipe arranged in a flue located behind the fireplace so that it becomes heated.
then enters the chamber D through the pipe and is rapidly drawn by the suction
or draught resulting from the high temperature existing in the retort A and by the
suction produced under the bell of the gasholder G, through the openings formed
in the bottom a and through the retorts A and E, expelling impure gases from the
retort A, and heating by its acquired heat, the charge within retort E, thus
preparing such charge for the subsequent operation. The said gas finally escapes
by the pipe and is conveyed either into the gasholder G, or into the fireplace to
support combustion.
The gas used for sweeping or clearing the retort instead of being blown in, may
be drawn in by suction. Or injurious gases present can be converted into neutral
gas by the addition of coal to the balls or briquettes of carbonate in the retort.
This coal should be added in picces of sufficient size to admit of its being easily
extracted from the baryta after calcination; or as an agglomerate arranged fo

page_text: entirely cover the interior of the retort in such a manner as to protect the latter
from the injurious action of the baryta.
The function of the coal, thus added and not incorporated with the balls or
briquettes, is only to unite with the carbonic acid and the oxygen present in the
retort and to convert them into an inert gas namely carbonic oxide.
The operation of charging and removing the charge from the retort A is identical
with that which has been described with reference to the retort B, care being taken
that the removal of the charge from the said retort A shall be effected whilst the
cover and the cocks are shut so as to prevent the return of the gases by suction,
and that the charging shall be effected whilst the piper is open so that the air shall
not be able to enter the retort. The baryta obtained in commercial purity by this
operation, which is almost continuous, is after it has been suitably cooled, removed
from the chamber D through the manhole g which is then at once closed.
I may
state that a current of carbonic oxide passed through the sulphide of barium, admixed
with its equivalent of sulphur, would also give at white heat anhydrous baryta
and carbon disulphide which would escape thus BaS + S + CO = BaO+ CS,:
but this method would be more expensive that the preceding one and the baryta
obtained would not be so pure, because the secondary action of CS, upon the BaO
formed, would partly reconvert the latter into sulphide of barium.
The fourth operation consists in the conversion of baryta into peroxide of
barium.
This operation is effected by the generally known method, and is mentioned here
merely to clearly shew the interconnection of all the operations of my process and
the perfect manner in which this operation in particular is effected in the same.
furnace, particularly in the retort C which is identical in arrangement and
operation to the retorts A and B.
The charge of baryta in the retort C is raised to a temperature of about 600° C.
and into it is forced by a pump through a piper and the lower chamber D" a current
of air which is purified by passing through a purifier P. The oxygen of the air
combined with the baryta, and the nitrogen escapes by the pipe ". The peroxide
of baryta thus formed is discharged into the chamber D₁ from which after cooling
it is removed, pulverized and sheltered from the air and moisture.
The fifth operation consists in the conversion of the peroxide of barium into
peroxide of hydrogen or oxygenated water.
It is known that peroxide of barium can be easily converted into oxygenated
water by various known methods. It should, however be remarked, that in my
process the carbonic acid obtained from the first operation is utilized, with great
advantage, to manufacture peroxide of hydrogen, as the residue of this manufacture
is pure carbonate of baryta, which material is thus supplied ready made for the
production of baryta according to the third operation herein before described. The
fifth operation is carried out in an apparatus similar to the vat M employed for
the conversion of the sulphide of barium into carbonate of baryta but that in the
coil, instead of causing water vapor, cold air or other cooling fluid is however
caused to circulate through the coil in the vat instead of steam, the carbonic acid
gas is introduced into the val by a pump instead of by a steam injector; and the
excess of carbonic acid gas escaping from the vat is returned to the gas holder.
Having now particularly described and ascertained the nature of the said inven-
uon and in what manner the same is to be performed I declare that what I
claim is
1. The hereinabove described process for the manufacture of peroxide of barium
or peroxide of hydrogen and comprising a series of successive operations for
converting sulphate of baryta into sulphide of barium then converting the sulphide
of barium thus obtained into carbonate of barium, then converting the carbonate
of barium into oxide of barium and the resulting oxide into peroxide of barium
and if desired utilizing the peroxide of barium thus obtained to produce peroxide
of hydrogen and sulphate or carbonate of baryta from which peroxide of barium

page_text: can be again obtained, the successive operations being effected substantially in the
manner and by the means herein before described with reference to and shewn in the
drawing annexed.
2. For carrying out the process above referred to a furnace constructed with
three sets of chambers each having an inlet and outlet adapted to be hermetically
closed, and comprising heating, calcining and cooling chambers arranged one above
another and capable of being placed in communication by means of valves or
bottoms such as a and b adapted to be operated from the outside of the furnace, the
arrangement being such as to admit on the one hand of the descent of material
from the upper chamber wherein it is heated to the intermediate chamber below
wherein it is calcined, and thence into the lower chamber wherein it is allowed to
cool and on the other hand to allow the ascent and escape of gases received during
or generated by the reaction the whole taking place out of contact with the
external atmosphere, the heating of the several chambers being effected simul-
taneously but at different temperatures to suit the various requirements by means
of a single combustion chamber substantially as hereinbefore described, whether or
not the said combustion chamber be constructed to burn carbonic oxide resulting
from the conversion of carbonate or sulphate of barium into oxide or sulphide of
barium respectively.
3. In the process above referred to effecting the calcination of the carbonate of
baryta after being formed into balls or briquettes with its equivalent only of coal,
in the presence of a current of neutral gas caused to flow through the retort by
pressure or by suction or in presence of coal either in the form of separate pieces
mixed with the balls or briquettes and capable of being readily removed from the
baryta formed by the calcination, or in the form of a carbonaceous lining to the
retort or vessel in which the calcination of the carbonate is effected substantially
.as described for the purpose specificd.
Dated this "1st day of March 1899
COMTE THOMAS BROCHOCKI,
By L. W., per F. B.