IMPROVEMENTS IN THE MANUFACTURE OF BARYTA AND ITS DERIVATIVES IN OBTAINING BY-PRODUCTS AND IN REVIVIFYING OR RECOVERING CERTAIN AGENTS EMPLOYED IN SUCH MANUFACTURE
Year: 1863

page_text: LETTERS PATENT to Richard Archibald Brooman, of No. 166, Fleet
Street, in the City of London, Patent Agent, for the Invention of
"IMPROVEMENTS IN THE MANUFACTURE OF BARYTA AND ITS DERIVATIVES IN
OBTAINING BY-PRODUCTS AND IN REVIVIFYING OR RECOVERING CERTAIN AGENTS
EMPLOYED IN SUCH MANUFACTURE."-A communication from abroad by
Julien Gabriel Lelong Burnet, of Paris, France.
Sealed the 2nd October 1863, and dated the 7th April 1863.
PROVISIONAL SPECIFICATION left by the said Richard Archibald
Brooman at the Office of the Commissioners of Patents, with his
Petition, on the 7th April 1863.
I, RICHARD ARCHIBALD BROOMAN, of 166, Fleet Street, in the City of
London, Patent Agent, do hereby declare the nature of the said Invention
for "IMPROVEMENTS IN THE MANUFACTURE OF BARYTA AND ITS DERIVATIVES IN
OBTAINING BY-PRODUCTS AND IN REVIVIFYING OR RECOVERING CERTAIN AGENTS
EMPLOYED IN SUCH MANUFACTURE," to be as follows:-
This Invention consists in certain processes, hereafter described, for the
manufacture of baryta and other compounds of barium, in the course of
which manufacture other products are obtained, and certain agents employed
are revivified or recovered.
1st. Preparation of baryta.-I mix native sulphate of baryta with from
10 to 15 per cent. more or less of mineral or vegetable coal, and submit it to
calcination. An apparatus suitable for this purpose is a furnace, with vertical

page_text: retorts of refractory carth and of oblate form, arranged symmetrically round
the axis of the kiln. The charging takes place at the top, and the discharge
at the bottom. To facilitate the decomposition vapour from tar or other car-
buretted gases may be made to pass into the retorts. When the conversion
of sulphate into sulphuret is sufficient, I dissolve the frit produced in boiling
water contained in an iron vessel furnished with a steam coil and an agitator.
The liquor then contains an oxysulphuret of barium, and it is at this point
that all the operations which form the subject of this Invention commence.
With regard to the residuum (magma) which dissolves with difficulty, I treat
it after decantation with hydrochloric or azotic acid which yields chloride of
barium or azotate of baryta. I now return to the treatment of the solution
cf oxysulphuret of barium. After decantation I treat it with potass or caustic
soda, and obtain a solution of baryta and sulphuret of potassium or of sodium;
the baryta crystallizes in the body of the liquor, and the sulphuret obtained
may be transformed into hyposulphito of potass or soda by a current of sul-
phurous acid, but I prefer the following process:-After decantation I treat
the liquor with a metallic oxide, which gives off its oxygen to the sulphur of
barium, and becomes transformed into an insoluble sulpburet, yielding at the
same time a solution of baryta, which is easily decanted. The oxides which
may be employed are those of lead, zinc, copper, iron, manganese, antimony,
bismuth, and tin, oxide of magnesium may be added to this list, but as it
produces a soluble sulphuret, it is necessary to separate the baryta for
crystallization instead of decanting, as when the other oxides named are
employed. Of all the oxides I prefer oxide of copper and oxide of zinc. The
operation is carried on in vessels similar to those before described. Boiling
facilitates the action, and when the liquor no longer precipitates a brown
acetate of lead the operation is terminated. After being left to settle, and
the water, after decantation containing baryta, yields by crystallization puro
crystallized baryta. The process just described would not be advantageous if
the oxide employed could only be used once, but I revivify it by roasting, and
it may thus be used indefinitely. During the roasting of the sulphuret tho
sulphur becomes converted into sulphurous acid, which I form into sulphuric
acid by the ordinary processes, so that I am thus enabled to obtain sulphuric
acid indirectly from sulphate of baryta. This sulphurous acid may also be used
to make sulphites or hyposulphites. Before submitting the metallic sulphuret to
roasting, it is necessary to deprive it completely of the baryta which it retains,
and which would prevent the proper action of or impede the roasting by
making the mass pasty. For this purpose I either leave the wet sulphuret
exposed to the air which will carbonate the baryta, in consequence of the great

page_text: difference in density of this carbonate from that of the metallic sulphuret, it
is easily separated therefrom, or I wash with water acidulated with hydro-
chloric acid, the solution being sufficiently weak to attack only the baryta,
and not the oxide of copper, slightly in excess, which has not been formed
into sulphuret, or I wash with water only several times; the small quantity of
baryta which is not removed by the washing becomes carbonated during the
roasting and the following washings; I cause the sulphuret of copper held in
suspension in the water to fall on to a long and almost horizontal table; the
sulphuret of copper is deposited, and the carbonate only remains in sus-
pension at the end of the table, and is carried off by the water. These
washings take place in vessels in which there are agitators. After a certain
number of operations in order to free the oxide of copper more completely
from foreign matters I make it fall in the state of dry powder into a conduit,
in which a powerful ventilator causes a strong current of air which drives
away the foreign matters, which are the lighter, and on gathering the deposits
they will be found sorted. During the roasting, which is performed in retorts
or on the bed of a furnace, I regulate the introduction of the air and
accelerate the operation by introducing steam. I operate in the same manner
with oxide of zinc. It does not answer so well as oxide of copper, and retains
more baryta, but the product obtained after a certain number of roastings
being a mixture of oxide of zinc and carbonate of baryta, may be employed
in glass making. The crystals of baryta are delivered into commerce in that
state, or by submitting them to heat I obtain monohydrated baryta, for
which purpose I cause the crystals to fall on a flat surface, or on inclined
tubes heated to the desired temperature, and the baryta reaches the end of
the surface or tubes deprived of nine equivalents of water, and in the state of
monohydrated baryta. If at the commencement of the processes constituting
the present Invention I use native carbonate of baryta instead of sulphate, as
it contains a little sulphate, which becomes converted into sulphuret, the
solution in water after the calcination is also treated by the oxides before
named, and they are afterwards subjected to the treatments before described.
I obtain anhydrous baryta by either of the two following processes:-I mix
together sulphate of baryta, sulphuret of barium, and about 10 per cent. of
magnesia, and calcine them out of contact with the air. I thus obtain
anhydrous baryta, and by dissolving it I obtain crystals; or I prepare anhydrous
baryta by decomposing azotate of baryta by heat, but (and this renders the
process industrially valuable) I introduce the nitrous gases disengaged upon
native carbonate of baryta, pounded or mixed in the state of powder with
I thus obtain new barytic salts, which on being decomposed, in their
water.

page_text: turn yield anhydrous baryta, and so on indefinitely. It is only necessary to
supply the loss of azotic acid which takes place in this process. I now pro-
ceed to describe the processes by which I obtain the different barytic salts.
2nd. Carbonate of baryta.-In the processes I have described two liquors
enter into the manufacture of carbonate of baryta, solution of oxysulphuret of
barium and solution of baryta obtained by the action of a metallic salt; I
proceed to describe what I obtain from these two liquors.
1. Solution of sulphuret of barium.-In treating this solution by carbonate
of potass or soda, I obtain carbonate of baryta and sulphuret of potassium or
of sodium, which I separate by decantation or washing. I also utilize this
solution in the following manner by introducing carbonic acid directly into it.
The carbonate should be as free as possible from sulphur; I have observed that
the free sulphur is precipitated a little at the commencement and especially
at the end of the carbonating. I divide the operation into three stages, I pre-
cipitate first for example about 2 of the carbonate which is to be formed and
decant, I pass a current of carbonic acid again into the decanted liquor to
precipitate the rds or thereabouts; the carbonate of baryta and the surplus
liquor serves to dissolve the product obtained from the calcination of the
sulphate of baryta with coal; 1 treat the first precipitate of the carbonate
which contains a little sulphur with a solution of potass or of soda which
removes the sulphur; I then wash.
2nd. Solution of baryta.-I treat this solution as follows:-Pure carbonate
of potass or of soda causes the formation of pure carbonate of baryta, which is
precipitated, and the liquor is then a solution of potash or of caustic soda,
which I concentrate for commercial uses; or I place native carbonate of baryta
in suspension in water and form a bicarbonate by a current of carbonic acid
if the carbonic acid acts under a pressure of several atmospheres, tho bicar-
bonate is concentrated to a degree commensurate with such pressure. By
then pouring in water of baryta in suitable proportion a precipitate is formed
which only requires drying to render it fit for commercial purposes. I obtain
lastly carbonate of baryta quite free from sulphur in the following manner and
which I generally adopt: The barytic solution on which I operate contains
traces of byposulphite of baryta not heretofore pointed out, for under the
oxidizing influence of the oxides a small quantity of polysulphuret of barium,
which is always present is formed into hyposulphite which is sufficient to give
traces of sulphur under the action of carbonic acid. The byposulphites
tending to become transformed into sulphate and into sulphur under an
oxidizing influence, I introduce chlorine either free or in the state of hypo-
chlorite; I even prepare for this purpose hypochlorite of baryta by causing

page_text: chlorine to be absorbed in a solution of baryta, but the use of free chlorine is
more economical, alkaline and alkalino-terrous hypochlorites may also bo
employed with advantage. When I have obtained the solution of baryta, I
allow the metallic sulphuret to deposit, I decant and submit the liquor in a
vat to the action of chlorine or bypochlorites, all the sulphate of baryta formed
and the free sulphur precipitate, and I cause the liquor to fall into carbonating
vessels into which I introduce carbonic acid. After the carbonating I drain
the product and dry it in a stove or otherwise. By this last process I obtain
a carbonate of very great purity.
3. Sulphate of baryta.-The operations and processes by which I form
precipitated sulphate of baryta are completely analogous to those just
described, for the carbonate, they therefore require no further description.
4. Azotate of baryta and chloride of barium.- I obtain these salts by
treating sulphuret of barium directly with azotic or hydrochloric acids; an
abundant disengagement of sulphuretted hydrogen taken place from which I
extract the sulphur, I burn it to convert it into sulphurous acid from which
sulphur is deposited on coming in contact in a chamber in an appropriate
apparatus with sulphuretted hydrogen produced in a second vessel at the same
time SO +2 HS-2 10+ 3 S. A very abundant source of azotate of
baryta or of chloride of barium results from the treatment by acids of the
residuum (magmas) of sulphuret.
5. Aluminate of baryta.-Soluble aluminate of baryta is a limpid and
colourless liquid like water; I obtain it free from sulphurets and iron by the
following processes:-1st, by calcining to a white heat in crucibles or on the bed
of a reverberatory furnace a mixture of native sulphate of baryta and of pure
ferruginous alumina in about equal proportions. After calcination the mixture
is pounded and submitted for some hours to the action of boiling water; the
filtered liquid will be a solution of aluminate of baryta ; 2nd, by submitting
the previous mixture, with the addition of about 5 per cent of coal, to a cherry
red heat, and introducing a current of steam; 3rd, by submitting to the samo
treatment a mixture of sulphuret of barium and aluminous earth in about
equal proportions or a matter of sulphuret of barium and of sulphate of
alumina; 4th, by submitting to the same treatment a mixture of chloride of
barium and of aluminous compound in about equal proportions.
In the second and third processes the steam carries off sulphurous com-
pounds, which are sulphuretted hydrogen, sulphurous acid, and hyposulphurous
acid which yield a liquid bolding sulphur in suspension. In the 4th process in
which chloride of barium is used the steam produces bydrochloric acid which
is collected and acted upon by pounded carbonate of lime to form chloride of

page_text: calcium and carbonic acid. The chloride of calcium when concentrated and
dried serves to produce chloride of barium by the process already known, and
the carbonic acid is collected for use in a gas holder. I now proceed to
describe the actions I obtain from this soluble aluminate of baryta to produce
the salts I have named. By pouring carbonate of soda into the aluminate
of baryta, until precipitation ceases, I obtain pure carbonate of baryta and pure
aluminate of soda.
6. Sulphate of baryta.-By causing sulphuric acid or sulphate of soda, to
act on the aluminate of baryta until precipitation ceases, I obtain a precipitato
of pure sulphate of baryta and alumina or aluminate of soda.
7. Monohydrated baryta.-By acting upon aluminate of baryta with quick
lime an insoluble aluminate of lime is formed and the filtered or decanted
liquor is a solution of baryta which by concentration and calcination becomes
monohydrated baryta.
In the employment of steam in the reactions or processes before described
the mixtures reduced to a firm paste and formed into lumps about the size
of cob nuts are placed in vertical or inclined retorts in order that a constant
current of steam may pass through the mass.
SPECIFICATION in pursuance of the conditions of the Letters Patent, filed
by the said Richard Archibald Brooman in the Great Seal Patent Office
on the 7th October 1863.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, RICHARD
ARCHIBALD BROOMAN, of 166, Fleet Street, in the City of London, Patent
Agent, send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her Letters
Patent, bearing date the Seventh day of April, in the year of our Lord
One thousand eight hundred and sixty-three, in the twenty-sixth year of Her
reign, did, for Herself, Her heirs and successors, give and grant unto me,
the said Richard Archibald Brooman, Her special licence that I, the said
Richard Archibald Broomar, my executors, administrators, and assigns, or
such others as I, the said Richard Archibald Brooman, my executors, admi-
nistrators, and 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

page_text: Man, an Invention for " IMPROVEMENTS IN THE MANUFACTURE OF BARYTA AND
ITS DERIVATIVES IN OBTAINING BY-PRODUCTS AND IN REVIVIFYING OR RECOVERING
CERTAIN AGENTS EMPLOYED IN SUCH MANUFACTURE," (communicated to me from
abroad by Julien Gabriel Lelong Burnet, of Paris, France,) upon the con-
dition (amongst others) that I, the said Richard Archibald Brooman, my
executors or administrators, by an instrument in writing under my, or their,
or one of their hands and seals, 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 Offico
within six calendar months next and immediately after the date of the said
Letters Patent.
NOW KNOW YE, that I, the said Richard Archibald Brooman, do hereby
declare the nature of the said Invention, and in what manner the same is to
be performed, to be particularly described and ascertained in and by the
following statement thereof, that is to say :-
This Invention consists in certain processes herein-after described for the
manufacture of baryta and other compounds of barium, in the course of which
manufacture other products are obtained, and certain agents employed are
revivified or recovered.
First. Preparation of baryta.-I mix native sulphate of baryta with from ten
to fifteen per cent. more or less of mineral or vegetable coal and submit it to cal-
cination. An apparatus suitable for this purpose is a furnace with vertical retorts
of refractory earth and of oblate form arranged syminetrically round the axis
of the furnace. The charging takes place at the top and the discharge at the
bottom. To facilitate the decomposition vapour from tar or other carburetted
gases may be made to pass into the retorts. When the conversion of sulphate
into sulphuret is sufficient I dissolve the frit produced in boiling water con-
tained in an iron vessel furnished with a steam coil and an agitator. The
liquor then contains an oxysulphuret of barium and it is at this point that all
the operations which form the subject of this Invention commence. With
regard to the residuum (magma), which will not dissolve or which dissolves
with difficulty, I treat it after decantation with hydrochloric or azotic acid which
yields chlorido of barium or azotate of baryta. I now return to the treatment
of the solution of oxysulphuret of bariuin; after decantation I treat it with
caustic potass or caustic soda and obtain a solution of baryta and sulphuret of
potassium or of sodium, the baryta crystallizes in the body of the liquor and
the sulphuret obtained may be transformed into hyposulphite of potass or soda
by a current of sulphurous acid. Sometimes I cause a current of carbonic
acid to pass through the sulphurets of potassium and of sodium and produce

page_text: the carbonates of these compounds. Or again, I am enabled to free them of
sulphur by the oxides described in order to reconvert them into caustic potass
or caustic soda which may thus be regenerated. The hydrosulphuric acid
produced by the action of carbonic acid upon these sulphurets is applicable
in the manufacture of sulphuric and sulphurous acids. But I prefer the follow-
ing process which I use regularly. After decantation I treat the liquor with a
metallic oxide which gives off its oxygen to the sulphur of barium and becomes
transformed into an insoluble sulphuret yielding at the same time a solution of
baryta which is easily decanted. The oxides which may be employed are
those of lead, zinc, copper, iron, manganese, antimony, bismuth, and tin.
Oxide of magnesium may be added to this list, but as it produces a soluble
sulphuret it is necessary to separate the baryta by crystallization instead of
decanting as when the other oxides named are employed. Of all the oxides
I prefer oxide of copper and oxide of zinc. The operation is carried on in
vessels similar to those before described. Boiling facilitates the action and
when the precipitate is no longer brown with acetate of lead the operation is
terminated. After being left to settle, the water after decantation containing
baryta yields by crystallization pure crystallized baryta. The process just
described would not be advantageous if the oxide employed could only be used
once, but I revivify it by roasting and it may thus be used indefinitely. During
the roasting of the sulphuret the sulphur becomes converted into sulphurous
acid which I form into sulphuric acid by the ordinary processes, so that I am
thus enabled to obtain sulphuric acid indirectly from sulphate of baryta.
This sulphurous acid may also be used to make sulphites or hyposulphites.
Before submitting the metallic sulphuret to roasting it is necessary to deprive
it completely of the baryta which it retains and which would provent the
proper action of or impede the roasting by making the mass pasty. For this
purpose I either leave the moist sulphuret exposed to the air, which will car-
bonate the baryta (in consequence of the great difference in density of this
carbonate from that of the metallic sulphuret it is easily separated therefrom),
or I wash with water acidulated with hydrochloric acid, the solution being
sufficiently weak to attack only the baryta and not the oxide of copper slightly
in excess which has not been formed into sulphuret, or I wash with water only
several times, the small quantity of baryta which is not removed by the wash-
ing becomes carbonated during the roasting and the following washings; I
cause the sulphuret of copper held in suspension in the water to fall on to a
long and almost horizontal table, the sulphuret of copper is deposited and only
the carbonate in suspension reaches the end of the table where it is carried of
by the water. These washings take place in vessels in which there are agita-

page_text: tors. After a certain number of operations in order to free the oxide of copper
more completely from foreign matters I make it fall in the state of dry powder
into a conduit in which a powerful ventilator causes a strong current of air
which drives away the foreign matters which are the lighter, and on gathering
the deposits they will be found sorted. During the roasting, which is performed
in retorts or on the bed of a furnace, I regulate the introduction of the air and
accelerate the operation by introducing steam, I operate in the same manner
with oxide of zinc. It does not answer so well as oxide of copper, and retains
a great deal of baryta, but the product obtained after a certain number of
roastings being a mixture of oxide of zinc and carbonate of baryta may be
employed in glass making. The crystals of baryta are delivered into commerco
in that state, or by submitting them to heat I obtain monohydrated baryta,
for which purpose I cause the crystals to fall on a flat surface or on inclined
tubes heated to the desired temperature, and the baryta reaches the end of the
surface or tubes deprived of its equivalents of water and in the state of mono-
bydrated baryta. If in commencing my manufacture I use native carbonate of
baryta instead of sulphate, as it contains a little sulphate which becomes con-
verted into sulphuret, the solution in water after the calcination is also treated
by the oxides before named, and they are afterwards subjected to the treat-
ments before described.
I obtain anhydrous baryta by either of the two following processes :-I mix
together sulphate of baryta, sulphuret of barium and about ten per cent. of
magnesia, and calcine them out of contact with the air. I thus obtain anby-
drous baryta, and by dissolving it I obtain crystals, or I prepare anhydrous
baryta by decomposing azotate of baryta by heat, but (and this renders the
process industrially valuable) I introduce the nitrous gases disengaged upon
native carbonate of baryta pounded or mixed in the state of powder with water;
I thus obtain new barytic salts which on being decomposed in their turn yield
anhydrous baryta and so on indefinitely it is only necessary to supply the loss
of azotic acid which takes place in this process.
I now proceed to describe the processes by which I obtain the different
barytic salts.
Second. Carbonate of baryta.- In the processes I have described two liquors
enter into the manufacture of carbonate of baryta, solution of oxysulphuret
of barium, and solution of baryta obtained by the action of a metallic oxide;
I proceed to describe what I obtain from these two liquors.
1. Solution of sulphuret of barium.-In treating this solution by carbonate
of potass or soda, I obtain carbonate of baryta and sulphuret of potassium or of
sodium which I separate by decantation and washing. I also utilize the solu-

page_text: tion in the following manner by introducing carbonic acid directly into it. The
carbonate should be as free as possible from sulphur. I may remark that the
free sulphur is precipitated a little at the commencement and especially at the
end of the carbonating. I divide this operation into three stages.
1 pre-
cipitate first, for example, about 5 of the carbonate which is to be formed
and decant. 1 pass a current of carbonic acid again into the decanted
liquor to precipitate the rds or thereabouts of the carbonate of baryta,
and the surplus liquor serves to dissolve the product obtained from the cal-
cination of the sulphate of baryta with coal. I treat the first precipitate of the
carbonate which contains a little sulphur with a solution of potass or of soda
which removes the sulphur, I then wash.
I sometimes use the following processes :-
First. Wet Process.-The precipitate of carbonate of baryta is treated
directly in the body of the liquor where it is formed, or after separation from
this liquor, and washing in water alone, or in alkaline water by sulphuret of
carbon, benzine, or bydrocarburets of light density and of a low boiling point
in order to dissolve all the sulphur which is precipitated at the same time as
the barytic carbonate. The excess of the dissolving matters is driven off by
heat, steam, or otherwise. The disolving matter evaporated yields the sulphur
it had dissolved.
Second. Dry Process. The carbonate of baryta mixed with sulphur
obtained from the decomposition of the sulphuret of barium by the passage of
a current of carbonic acid into the body of a solution of sulphuret of barium is
well washed, and placed in a closed vessel, in which it is heated by passing
into it a current of the following gases, alone or mixed, first, carbonic acid;
second, bydrogen and carbonated hydrogen; third, coal gas; fourth, gas
derived from a hydrocarburet in a state of vapour; fifth, vapour of water alone
superheated, or vapour from water decomposed by incandescent coal; sixth,
carbonic oxide, and generally all gases and vapours deprived of oxygen. It is
not necessary that the temperature should be very intense, generally it need
not be carried beyond that at which sulphur fuses. Again, after washing the
carbonate of baryta mixed with sulphur, it may be mixed with coal, tarry
matters, oils, and the like, and the whole may be heated in a closed vessel.
Among other products, sulphuret of carbon is disengaged, and may be col-
lected and used in the wet process as before described. In passing the before-
named gases over a mixture of sulphate of baryta and coal heated in a closed
vessel, the separation of the sulphur from the sulphate of baryta is facilitated,
whereby a great portion of the latter is thus brought back to the state of
baryta, or carbonate of baryta. In order to obtain baryta from native car-

page_text: bonate of baryta, I pulverize and mix it with a given quantity of wood, char-
coal, or coal reduced to a fine powder. I subject this mixture to beat to
drive off the carbonic acid; at the same time baryta and sulphuret of barium
are formed, the latter in proportion to the sulphuret of barium contained in
the ore, in this case after solution, I use the same means to get rid of the
sulphur and sulphurous matters.
2. Solution of baryta.-I treat this solution as follows:-Pure carbonate
of potass or of soda causes the formation of pure carbonate of baryta, which is
precipitated, and the liquor is then a solution of caustic potash, or of caustic
soda, which I concentrate for commercial uses. Or, I place native carbonate
of baryta in suspension in water, and form a bi-carbonate by a current of
carbonic acid. If the carbonic acid acts under a pressure of several atmo-
spheres, the bi-carbonate is concentrated to a degree commensurate with such
pressure. By then pouring in water of baryta in suitable proportion, a pre-
cipitate is formed which only requires drying to render it fit for commercial
purposes. I obtain carbonate of baryta quite free from sulphur in the following
manner, and which I generally adopt. The barytic solution on which I
operato contains traces of hyposulphite of baryta not heretofore pointed out,
for under the oxidizing influence of the oxides a small quantity of polysul-
phuret of barium, which is always present, is formed into hyposulphite, which
is sufficient to give traces of sulphur under the action of carbonic acid. The
byposulphites tending to become transformed into sulphate and into sulphur,
under an oxidizing influence, I introduce chlorine either free or in the state of
bypochlorite. I prepare for this purpose bypochlorite of baryta by causing
chlorine to be absorbed in a solution of baryta, but the use of free chlorine is
more economical. Alkaline and alkalino-terrous hypo-chlorites may also be
employed with advantage. When I have obtained the solution of baryta, I
allow the metallic sulphuret to deposit. I decant and submit the liquor in a
vat to the action of chlorine or hypochlorites, all the sulphate of baryta formed,
and the free sulphur precipitate, and I lead the liquor into carbonating vessels
into which I introduce carbonic acid. After the carbonating I drain the
product, and dry it in a stove or otherwise. By this last process I obtain a
carbonate of very great purity, and such as has never been heretofore indus-
trially obtained.
3. Sulphate of baryta.-The operations and processes by which I form pre-
cipitated sulphate of baryta are completely analogous to those just described
for the carbonate, they therefore require no further description.
4. Azotate of baryta and chloride of barium.-I obtain these salts by
treating sulphuret of barium directly with azotic or hydrochloric acids, an

page_text: abundant disengagement of sulphuretted hydrogen takes place, from which I
extract the sulphur. I burn it to convert it into sulphurous acid, from which
sulphur is deposited on coming in contact in a chamber in a suitable appa-
ratus with sulphuretted hydrogen produced in a second vessel at the same
time. SO+2 IIS=2 HO+3 S. A very abundant source of azotate of
baryta or of chloride of barium results from the treatment by acids of the
residuum (magmas) of sulphuret.
5. Aluminate of baryta.-Soluble aluminate of baryta is a limpid and
colorless liquid like water. I obtain it free from sulphurets and iron by the
following processes:-First, by calcining to a white heat in crucibles, or on the
bed of a reverberatory furnace a mixture of native sulphate of baryta and of
pure or ferruginous alumina in about equal proportions. After calcination
the frit is pounded and submitted for some hours to the action of boiling
water; the filtered liquor will be a solution of aluminate of baryta. Second, by
submitting the previous mixture, with the addition of about five per cent. of coal,
to a cherry-red heat, and introducing a current of steam. Third, by submitting
to the same treatment a mixture of sulphuret of barium and aluminous carth
in about equal proportions, or a mixture of sulphuret of barium and of sul-
phate of alumina. Fourth, by submitting to the same treatment a mixture of
chloride of barium and of aluminous compound in about equal proportions.
In the second and third processes the steam carries off sulphurous compounds,
which are sulphuretted bydrogen, sulphurous acid, and hyposulphurous acid,
which yield a liquor holding sulphur in suspension. In the fourth process in
which chloride of barium is used, the steam produces hydrochloric acid, which
is collected and acted upon by pounded carbonate of lime to form chloride of
calcium and carbonic acid. The chloride of calcium when concentrated and
dried serves to produce chloride of barium by the process already known,
and the carbonic acid is collected in a gasholder.
I now proceed to describe the actions I obtain from this soluble aluminate of
baryta to produce the salts I have named. By pouring carbonate of soda into
the aluminate of baryta until precipitation ceases, I obtain pure carbonate of
baryta and pure aluminate of soda.
6. Sulphate of baryta.-By causing sulphuric acid or sulphate of soda to
act on the aluminate of baryta until precipitation ceases, I obtain a precipitate
of pure sulphate of baryta and alumina or aluminate of soda.
7. Monohydrated baryta.- By acting upon aluminate of baryta with quick-
lime, an insoluble aluminate of lime is formed, and the filtered or decanted
liquor is a solution of baryta, which by concentration and calcination becomes
monohydrated baryta.

page_text: In the employment of steam in the actions or processes before described,
the mixtures reduced to a firm paste, and formed into lumps about the size of
cob nuts, are placed in vertical or inclined retorts, in order that a constant
current of steam may pass through the mass.
And having now described the nature of the said Invention, and in what
manner the same is to be performed, I declare that I claim,―
First, the manufacture of baryta and its derivatives, by the means and in
manner herein-before described.
Second, the manufacture of baryta by the employment of the oxides as herein-
before described, and the utilization of the sulphurous acid disengaged in pro-
ducing sulphuric acid.
Third, the indefinite utilization of nitrous vapours in the manufacture of
anhydrous baryta.
Fourth, the production of caustic potash or caustic soda as by-products in
the manufacture of the carbonate and the sulphate of baryta, and the employ-
ment of chlorine or bypochlorites in order to obtain the caustic potash or
caustic soda free from sulphur.
Fifth, the methods berein-before described of preparing aluminate of baryta
and its derivatives, obtained in manner herein-before described.
In witness whereof, I, the said Richard Archibald Brooman, have here-
unto set my hand and seal, this Seventh day of October, One thousand
eight hundred and sixty-three.
K. A. BROUMAN. (L.B.)