AN IMPROVED PROCESS AND APPARATUS FOR OBTAINING CARBONATE OF STRONTIA FROM THE RESIDUES IN THE MANUFACTURE OF SUGAR
Year: 1882

page_text: LETTERS PATENT to David Sidersky and Hermann Probst, of Rositz,
Germany, for an Invention of "AN IMPROVED PROCESS AND APPARATUS
FOR OBTAINING CARBONATE OF STRONTIA FROM THE RESIDUES IN THE
MANUFACTURE OF SUGAR,"
PROVISIONAL SPECIFICATION left by the said David Sidersky and
Hermann Probst at the Office of the Commissioners of Patents on the
29th July 1882.
DAVID SIDERSKY, and HERMANN PROBST, of Rositz, Germany, "AN IMPROVED
PROCESS AND APPARATUS FOR OBTAINING CARBONATE OF STRONTIA FROM THE
RESIDUES IN THE MANUFACTURE OF SUGAR
"
This invention relates to an improved process and apparatus for the preparation
of carbonate of strontia from the residues in the manufacture of sugar by means
of strontianite.
When the burnt strontianite is slacked to produce crystals of hydrate of strontia,
a slimy residuum is obtained which contains large quantities of marl and chalk,
and very considerable quantities of strontia. The separation of the strontia from
the aforesaid slime, has hitherto been carried out in a very imperfect manner, the
process employed consisting in moulding the slime into the form of bricks, drying it,
and again heating and slacking it, whereby a certain amount of the strontia is
again crystallized. But in this operation another slimy residuum is obtained
from which it is not possible to obtain the strontia by the same process.
In the process comprised in the said invention the strontia can be separated
from either the first or second residuum of the slimy compound, in the shape
of carbonate of strontia; and the operation is performed as follows by means of the
apparatus hereinafter described, or other apparatus constructed and arranged to
operate on the same principles.
The slime is conducted through a large pipe provided with a stone receiver,
into a hopper, and, after it has been reduced to small fragments by passing it

page_text: through a crushing mill, it is boiled in a suitable vessel for a few minutes with
an
excess of hydrochloric acid, which can be supplied from another vessel
provided with a measuring scale; the whole of the strontia is thus dissolved. The
boiling is effected by means of a serpentine steam pipe arranged within the first
named vessel. Over the said pipe between two sieves is a filter bed of gravel
through which, after opening a cock, the strongly acid solution is filtered and
thus becomes free of marl. The clear solution then passes, according to which cock
has been opened, either into one or the other of two vats provided with agitating
apparatus, a siphon pipe with asbestos packed joints and a serpentine steam pipe.
The clear solution which is introduced into such vat is reacted upon with
moderately diluted sulphuric acid, by means of the agitating apparatus whereby
the strontia is precipitated as finely pulverized sulphate of strontia, whilst the
remainder is in solution. The precipitate settles and the solution over it can
easily be removed by means of the said siphon tube which can be turned round.
Thereupon the precipitate washed with water and after this latter has been
decanted off, it is boiled for a suitable length of time in the same vat, by means
of the surpentine steam pipe, with a solution of soda or potash, or with residuary
liquors from distilleries, of the required concentration whereby the sulphate of
strontia is converted into carbonate of strontia which is in suspension in a solution
of sulphate of soda or of potash, as the case may be, and can be separated from it
by means of a suction filter.
In the treatment with sulphuric acid, an excess of the latter should be avoided,
in order to prevent the formation of sulphate of lime. Should such have occurred
through carelessness or inattention, wariu sulphate of ammonia should be added to
the solution to dissolve the sulphate of lime. The sulphate of ammonia is contained
in a suitable vessel.
In case there should be some iron present in the slimy compound to be treated,
ammonia is added to it, from another vessel to cause it to separate together with
the marl. I also provide a vessel for sulphuric acid, and another for the soda
solution or for the residuary liquors from distilleries.
All these vessels are provided with graduated level indicators, so that the
workmen are always able, according to the indications, to performn their operations
with exactly the required quantities.
The arrangement with two vats is preferable because whilst the operation of
separating the strontia from a quantity of strontia solution, in the shape of
carbonate of strontia, goes on in the one vat another operation can be begun in
the adjacent one and thus a continuous working is rendered possible.
The carbonic acid set free in the first operation can be utilized if desired.

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent filed
by the said David Sidersky and Hermann Probst in the Great Seal
Patent Office on the 29th January 1883.
DAVID SIDERSKY and HERMANN PROBST, of Rositz, Germany. "AN IMPROVED
PROCESS AND APPARATUS FOR OBTAINING CARBONATE OF STRONTIA FROM
RESIDUES IN THE MANUFACTURE OF SUGAR "
THE
This Invention relates to an improved process and apparatus for the preparation
of carbonate of strontia from the residues in the manufacture of sugar by means
of strontianite.
When the burnt strontianite is slacked to produce crystals of hydrate of strontia.
a slimy residue is obtained which contains large quantities of marl and chalk, and
very considerable quantities of strontia. The separation of the strontia, from the
aforesaid slime, has hitherto been effected in a very imperfect manner, the process
usually employed consisting in moulding the slime into the form of bricks, drying
it, and again heating it and slacking it whereby a certain amount of the strontia is
again crystallized. But in this operation another slimy residue is obtained, from
which it is not possible to extract the strontia by a similar process.
By the process comprised in the present invention the strontia can be separated
from either the first or second residue of the slimy compound, in the shape of
carbonate of strontia, and the operation is performed as hereinafter set forth by
means of the apparatus shewn, or other suitable apparatus.
The slime is conducted through a large pipe a into a hopper a¹, from whence it
passes into the vessel A. after it has been reduced to small fraginents by the
crushing mill B; it is then boiled for a few minutes in the said vessel with an
excess of bydrochloric acid, which can be supplied from the vessel C provided
with a graduated gauge; the whole of the strontia is thus dissolved. The boiling
is effected by means of the serpentine steam pipe d arranged within the vessel A.
Over the said pipe between two sieves is a filter-bed e of gravel, through which,
after opening the cock, the strongly acid solution is filtered, whereby it becomes
free from marl. The clear solution then passes, according to whether the cock g,
or gl has been opened, into one, or the other, of two vats D D'. These vats are
each provided with agitating apparatus, a pipe K with asbestos packed joints, and
a serpentine steam pipe h. The clear solution which is introduced into such vat is
reacted upon, with moderately diluted sulphuric acid, by means of the agitating
apparatus, whereby the strontia is precipitated as finely pulverized sulphate of
strontia, whilst the remainder is in solution. The precipitate settles and the solu-
tion over it can easily be removed by means of the said tube K which can be
turned down. The precipitate is then washed with water, and, after this latter has
been drawn off, it is boiled for a suitable length of time in the same vat by means
of the serpentine ateam pipe with a solution of soda or potash, or with residuary
liquors from distilleries, of the required concentration, whereby the sulphate of
strontia is converted into carbonate of strontia, which is in suspension in a solution
of sulphate of soda or of potash as the case may be, and can be separated from it
by means of a suction-filter E.
In the treatment with the sulphuric acid, an excess of the latter should be
avoided, in order to prevent the formation of sulphate of lime. Should such have
occurred through carelessness or inattention, warm sulphate of ammonia should be
added to the solution to dissolve the sulphate of lime The sulphate of ammonia is
contained in a suitable vessel I.
In case there should be some iron present in the slimy compound to be treated,
ammonia is added to it, from another vessel F, to cause it to separate, together with

page_text: the marl. We also provide a vessel G for sulphuric acid, and another vessel H for
the soda solution or for the residuary liquors from distilleries.
All these vessels are provided with graduated gauges so that the workinen are
always able, according to the indications, to perform their operations with exactly
the required quantities..
The arrangement with the two vats D, D' is preferable, because, whilst the
operation of separating the strontia from a quantity of strontia solution in the
shape of carbonate of strontia goes on in the one vat, another operation can be
begun in the adjacent one, and thus a continuous working is rendered possible.
The carbonic acid set free in the first operation, in the vessel A, can be utilized
if desired.
Having thus fully described our said invention and the manner of performing
the same we wish it understood that we claim
First. The improved process for obtaining carbonate of strontia from the residues
in the manufacture of sugar by means of strontianite, which process consists in
boiling the slimny compound with hydrochloric acid, filtering the strongly acid
solution, treating the same with moderately diluted sulphuric acid whereby the
strontia is precipitated as sulphate of strontia, removing the solution therefrom,
washing the precipitate with water, which is afterwards drawn off, and finally
treating the sulphate of strontia with a solution of soda or potash, or with
residuary liquors from distilleries, substantially as described.
Second-The combination of the vessel A provided with the crushing mill, filter,
and serpentine steam pipe, with the vats D, D¹ provided with agitating apparatus,
the filter E, and the vessels C, F, G, H and I provided with graduated gauges, the
vessels C and F being connected with the vessel A, and the other three vessels with
the vats D, D¹, by means of pipes provided with taps or cocks, all substantially as,
and for the purposes, specified.
In witness whereof we the said David Sidersky and Hermann Probst have
hereunto set our hands and seals this 24th day of January in the year
of our Lord one thousand eight hundred and eighty three.
DAVID SIDERSKY
(L.S.)
HERMANN PROBST (L.S.)