Improvements in Extracting Sugar from Molasses by Means of Barium Hydroxy-sulphide, and Recovering the same from the Resulting By Products.
Year: 1896

page_text: Date of Application. 20th July. 1896
Complete Specification Left, 23rd Mar., 1897-Accepted, 12th June, 1897
Complete Specification Left, 23rd Mar., 1897-Accepted, 12th June, 1897
PROVISIONAL SPECIFICATION.
Improvements in Extracting Sugar from Molasses by Means of
Barium Hydroxy-sulphide, and Recovering the same from the
Resulting By Products.
I, WALTHER FELD, of Hönningen a/Rhein in den Silven in the German
Empire, Chemist, do hereby declare the nature of this invention to be as
follows:-
Sugar has been extracted from molasses by means of barium hydroxysulphide
either alone or in combination with alkali hydroxide sulphuretted hydrogen being
produced from the residue for the purpose of converting it into sulphurous or
sulphuric acid, so as by the decomposition of the barium saccharate resulting from
the sugar extraction from the molasses to obtain with the sugar, barium sulphite or
sulphate, which compounds are then converted with carbon into barium sulphide,
and this by treatment with water is converted into barium hydroxysulphide which
can be used again for precipitation of sugar from molasses. In this process there
are almost unavoidable losses of sulphur, which though small in amount interfere
with the continuity of the process, and must therefore be made up for. The object
of the present invention is to make up for these losses of sulphur in order to avoid
interruption of the continuous process for extraction of sugar from molasses with
barium hydroxysulphide.
For this purpose, the supply of the sulphur is effected by mixing alkali sulphate
with the residue. The residue when barium hydroxysulphide is used alone for
extraction of the sugar, contains half of the baryta employed or according
to the solubility of the barium saccharate in water it may be a little more than
half.
When an equivalent mixture of barium hydroxysulphide with alkali hydroxide
is employed, the residue contains the whole of the baryta used.
By this process barium sulphate is produced, the reactions being such as appear
in the following equations:

page_text: By treating the liquid with carbonic acid the sulphuretted hydrogen is expelled
from the alkali sulpbide, and by calcining the residue alkaline carbonate is
obtained.
The advantage of the process consists in the simple and easy manner in which
loss of sulphur is made up for, and valuable alkaline carbonate obtained.
Preferably, in order to obtain the valuable potassium carbonate, the sulphate
employed is potassium sulphate.
Dated this 20th day of July 1898
ABEL & IMRAY,
Agents for the Applicant.
Improvements in Extracting Sugar from Molasses by Means of
Barium Hydroxy-sulphide, and Recovering the same from the
Resulting By Products.
I, WALTHER FELD, of Honningen a/Rhein in den Silven, in the German
Empire, Chemist, 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 :-
Sugar has been extracted from molasses by means of barium hydroxysulphide
either alone or in combination with alkali hydroxide, sulphuretted hydrogen being
produced from the residue for the purpose of converting it into sulphurous or
sulphuric acid, so as by the decomposition of the barium saccharate resulting from
the sugar extraction from the molasses to obtain with the sugar barium sulphite or
sulphate, which compounds are then converted with carbon into barium sulphide,
and this, by treatment with water is converted into barium hydroxysulphide which
can be used again for precipitation of sugar from molasses. In this process there
are almost unavoidable losses of sulphur, which, though small in amount, interfere
with the continuity of the process, and must therefore be made good. The object
of the present invention is to make up for these losses of sulphur in order to avoid
interruption of the continuous process for extraction of sugar from molasses with
barium hydroxysulphide.
For this purpose, the supply of the sulphur is effected by mixing alkali sulphate
with the residual liquid. The amount of alkali sulphate used depends on the loss
of sulphur, and in practical working such loss can be determined by analysis, but
as a general rule it would be such that about one molecule of potassium sulphate
would be required for each molecule of barium saccharate or barium hydroxy-
sulphide. The residual liquid when barium hydroxysulphide is used alone for
extraction of the sugar, contains half of the baryta employed, or, according
to the solubility of the barium saccharate in water, it may be a little more than
half.
When an equivalent mixture of barium hydroxysulphide with alkali hydroxide
is employed, the residual liquid contains the whole of the baryta used.
By this process barium sulphate is produced, the reactions being such as appear
in the following equations:

page_text: (2.)
Ba(SH), + K,SO₁
Barium
K,SO = 2 KSH + BaSO.
Potassium
Barium
hydrosulphide
sulphate
sulphate
Potassium
hydrosulphide
The barium is precipitated and when separated from the liquid in the usual
manner by filtration etc., is converted by reduction with carbon into barium
sulphide which by treatment with water is converted into barium hydroxysulphide,
available for again extracting sugar.
The liquid freed from the barium sulphate contains alkali combined partly with
sulphuretted hydrogen, partly with sugar, a small amount of which is present.
Also free alkali may be present in solution.
By treating the liquid with carbonic acid the sulphuretted hydrogen is expelled
from the alkali sulphide, and by calcining the residue alkaline carbonate is
obtained.
The advantage of the process consists in the simple and easy manner in which
loss of sulphur is made up for, and valuable alkaline carbonate obtained.
Preferably, in order to obtain the valuable potassium carbonate, the sulphate
employed is potassium sulphate.
Having now particularly described and ascertained the nature of this iuven-
tion and in what manner the same is to be performed, I declare that what I
claim is :-
The herein described process for extracting sugar from molasses by means of
barium hydroxysulphide alone or admixed with alkali hydroxide, by mixing the
residual liquid, when separated from the precipitated barium saccharate, with
alkali sulphate and, after removal of the barium sulphate, (which is reduced by
carbon to barium sulphide, which again is converted by water into barium hydroxy-
sulphide, available for subsequent extraction of sugar) then treating the said liquid
with carbonic acid to liberate sulphuretted hydrogen, which is converted into
sulphurous or sulphuric acid that can be used for decomposing the barium
saccharate, whilst alkali carbonate is obtained by calcination of the residue,
substantially as described.
Dated this 23rd day of March 1897.
ABEL & IMRAY,
Agents for the Applicant.