IMPROVEMENTS IN THE MANUFACTURE OF SUGAR
Year: 1881

page_text: LETTERS PATENT to Alexander Melville Clark, of 53, Chancery Lane, in the
County of Middlesex, Patent Agent, for an Invention of "IMPROVEMENTS
IN THE MANUFACTURE OF SUGAR." A communication from abroad by Jean
Baptiste Marie Prosper Closson. of Paris France
PROVISIONAL SPECIFICATION left by the said Alexander Melville Clark
at the Office of the Commissioners of Patents on the 4th April 1881.
ALEXANDER MELVILLE CLARK, of 53, Chancery Lane, in the County of Middlesex,
Patent Agent.
"IMPROVEMENTS IN THE MANUFACTURE OF SUGAR." [A com-
munication from abroad by Jean Baptiste Marie Prosper Closson, of Paris, France.]
It is generally admitted that the preferable process of extracting sugar is that
known as the baryta process. In this process saccharate of baryta is formed
1665 parts (by weight) of crystallised baryta being theoretically required for
171 parts of sugar. These two bodies mix in the cold without causing any
turbidity; but if the solution be heated to about 100° C. the saccharate of baryta
is precipitated unaccompanied by any considerable proportion of foreign matter.
One may also operate in the cold, provided certain necessary precautions are
adopted. When exposed in water to a current of carbonic acid the precipitate
(which may moreover be washed) becomes decomposed, insoluble carbonate of
baryta being deposited and the sugar remaining in solution. It then only remains
to filter off to wash the carbonate with water, to transfer the saccharine solution
to the evaporating apparatus, and finally to crystallise.
Various modifications of this process have been proposed. It is thus that sugar
is extracted from molasses by forming a saccharate of baryta, which is then treated
with sulphate of iron to form insoluble sulphate of baryta and oxide of iron. It is
however unnecessary to enlarge further upon this process.
The method or process of this Invention does not exclude any of these various
modifications nor any of the various applications thereof. It consists in the
method of forming the saccharate of baryta by the employment of chloride of
barium in lieu of caustic baryta. First I form with the saccharine liquors, juices,
Puias 11

page_text: or molasses, insoluble saccharate of lime, and then for every 171 parts (by weight)
of sugar contained I add (in theory) to the solution 104-14 parts of chloride of
barium, thereby forming saccharate of baryta which precipitates, and chloride of
calcium which remains in solution. The saccharate of baryta is treated as in the
processes already known, and yields sugar and carbonate of baryta. By heating
this carbonate of baryta with hydrochloric acid, chloride of barium is again formed
for use in a new operation. Thus (apart from loss) the only expense is that of
35.5 parts of pure hydrochloric acid, or say about 100 parts of commercial hydro-
chloric acid for 171 parts of sugar, or 60 parts of commercial hydrochloric acid
for 100 parts of sugar. This expense varies according to locality, but would in
any case be very small.
I may employ chloride of strontium in a similar manner by observing the
necessary conditions to ensure the insolubility and proper precipitation of the
chloride of strontium. In this process the sugar is always preserved in the first
place by the lime, and afterwards by the baryta, until the moment when it is
dissolved in pure water to form the syrup from which to obtain the crystals of
sugar. The process of extraction of sugar by means of baryta is generally
acknowledged to be the best, but the excessive cost of this base has hitherto
retarded its employment. In the process of this Invention the cost of the hydro-
chloric acid is substituted for that of the baryta, and in this way the necessary
degree of economy is attained to permit of the practical application of the process.

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent filed
by the said Alexander Melville Clark in the Great Seal Patent Office on
the 4th October 1881.
ALEXANDER MELVILLE CLARK, of 53, Chancery Lane, in the County of Middlesex,
Patent Agent. "IMPROVEMENTS IN THE MANUFACTURE OF SUGAR." A
communication from abroad by Jean Baptiste Marie Proper Closson, of Paris,
France.
It is generally admitted that the preferable process of extracting sugar is that
known as the baryta process. In this process saccharate of baryta is formed,
1665 parts (by weight) of crystallised baryta being theoretically required for 171
parts of sugar. These two bodies mix in the cold without causing any turbidity,
but if the solution be heated to about 100° C. the saccharate of baryta is precipitated
unaccompanied by any considerable proportion of foreign matter. One may also
operate in the cold, provided certain necessary precautions, are adopted. When
exposed in water to a current of carbonic acid the precipitate (which may moreover
be washed) becomes decomposed, insoluble carbonate of baryta being deposited
and the sugar remaining in solution. It then only remains to filter off, to wash the
carbonate with water, to transfer the saccharine solution to the evaporating
apparatus, and finally to crystallise.
Various modifications of this process have been proposed. It is thus that sugar
is extracted from molasses by forming a saccharate of baryta, which is then treated
with sulphate of iron to form insoluble sulphate of baryta and oxide of iron. It is
however unnecessary to enlarge further upon this process.
The method or process of this Invention does not exclude any of these various
modifications nor any of the various applications thereof. It consists in the
method of forming the saccharate of baryta by the employment of chloride of
barium in lieu of caustic baryta. First I form with the saccharine liquors, juices,
or molasses insoluble saccharate of lime, and then for every 171 parts (by weight) of
sugar contained I add (in theory) to the solution 104.14 parts of chloride of barium,
thereby forming saccharate of baryta which precipitates, and chloride of calcium
which remains in solution. The saccharate of baryta is treated as in the processes
already known, and yields sugar and carbonate of baryta. By treating this
carbonate of baryta with hydrochloric acid chloride of barium is again formed for
use in a new operation. Thus (apart from loss) the only expense is that of 35.5
parts of pure hydrochloric acid, or say about 100 parts of commercial hydrochloric
acid for 171 parts of sugar, or 60 parts of commercial hydrochloric acid for 100
parts of sugar. This expense varies according to locality, but would in any case
be very small. I may employ chloride of strontium in a similar manner by
observing the necessary conditions to ensure the insolubility and proper precipitation.
of the saccharate of strontian.
In this process the sugar is always preserved, in the first place by the lime and
afterwards by the baryta, until the moment when it is dissolved in pure water to
form the syrup from which to obtain the crystals of sugar. The process of
extraction of sugar by means of baryta is generally acknowledged to be the best,
but the excessive cost of this base has hitherto retarded its employment. In the
process of this Invention the cost of the hydrochloric acid is substituted for that
of the baryta or of the strontian, and in this way the necessary degree of economy
is attained to permit of the practical application of the process. Moreover, as the

page_text: tribasic saccharate of strontian is soluble at a boiling heat and deposits two
equivalents of strontian at the ordinary temperature, the strontian may thus be
prepared in the wet way.
In witness whereof, I, the said Alexander Melville Clark, have hereunto set
my hand and seal, this Fourth day of October, A.D. 1881.