Improvements in the Process of Extracting Saccharine Matters.
Year: 1885

page_text: Improvements in the Process of Extracting Saccharine Matters.
I, HERBERT JOHN HADDAN, of 67 Strand, in the City of Westminster, Civil
Engineer, do hereby declare the nature of said invention for IMPROVEMENTS IN
THE PROCESS OF EXTRACTING SACCHARINE MATTERS, a communication to me from
abroad by Konrad Trobach of 104 Leipziger Strasse, Berlin, Germany, Manufacturer,
to be as follows:-
This invention consists in a process for transforming impure saccharine solutions,
such as molasses, starch-sugar solutions, and sweet-mash, into a solid sacchariferous
substance by mixing the same with sawdust or other reduced vegetable matter
which absorbs the solution into the pores and cells, for the purpose of obtaining
sugar. Also in preparation of the sawdust or other reduced vegetable matter for
the absorption of impure saccharine solutions with a view to extracting sugar from
them, and consisting in separating by means of hot alcohol the elements which are
soluble in alcohol. Also in the lixiviation of the sugar by means of hot, strong
alcohol, from the solid sacchariferous vegetable substance transformed by mixing
impure saccharine solutions, such as molasses, starch-sugar solutions or sweet mash
with reduced wood or other fibrous substance, the non-saccharine elements remaining
behind. Also in Marguerite's process for the separation of sulphates from the
molasses, the improvement, obtained by treating thinned molasses with a mixture
of alcohol and water of 50 to 60 degrees, instead of inspissating the molasses
to 47-48° Beaume and employing alcohol of 85%. And also in the employment
of chamois-leather as a filtering medium for saccharine solutions in which solid
bodies are suspended in very fine particles or in the form of sline.
°
Instead of 85% of alcohol I employ only 50 to 60% for thinning molasses, or
an equivalent quantity of alcohol of about 90 ° and water, mixing it thoroughly
by stirring with a quantity of ordinary sulphuric acid corresponding at the utmost
to the salts contained in the molasses.
For the filtration of the juices amongst which the impurities are distributed in
very fine and slimy particles I had to seek for quite a peculiar filtering material,
and this I found by employing very uniform pieces of chamois-leather which
are inserted in the frames of the filtering presses or grooves or are employed as
filtering hose.

page_text: The treatment of saccharine solutions with sawdust and other fibrous substances.
Since the sugar must be extracted from the mixture of saccharine solution and
sawdust by means of hot alcohol it is necessary in the first place, to remove the
elements of the wood, which would be soluble in alcohol, by extracting them by
means of hot alcohol.
The material so treated can be often again employed in future operations.
So much of the sawdust & is now thoroughly mixed with the saccharino solution
under treatment until the whole feels like an almost dry, soft powder.
The quantity of the sawdust is, of course, regulated by the strength of the
saccharine solution.
It is advisable to heat the molasses while the sawdust is being added.
In this case the absorption of the saccharine solution together with its impurities
takes place in a very complete manner, so that the sawdust retains on its surface
only small insignificant quantities of the impurities.
о
For the extraction of the sugar I use hot strong alcohol (I prefer it about
80 to 90% Tralles; for starch-sugar solutions, in which only dextrin has to be
eliminated, alcohol of 60 to 70 % will suffice)-in the way of ordinary lixiviation,
as in the case of beetroot or other solid sacchariferous bodies, while the non-
saccharine substances absorbed into the cells are not carried off by the strong
alcohol. Of course, according to the strength of the hot alcohol, the process of
lixiviation must be continued and repeated until complete.
Dated this 2nd day of Feb 18OK

page_text: I, HERBERT JOHN HADDAN of 67 Strand, in the City of Westminster, Civil
Engineer, do hereby declare the nature of this invention, a communication to me
from abroad by Konrad Trobach, of 104 Leipziger Strasse, Berlin, Germany,
Manufacturer, and in what manner the same is to be performed, to be particularly
described and ascertained, in and by the following statement :-
The present invention depends on the fact, that saccharine solutions are absorbed
by sawdust, rasped or planed wood, cellulose and other fibrous matter and especially
dried residual products obtained in the manufacture of beet sugar (by the diffusion
process) in such a manner, that there results an apparently dry substance
containing sugar in the cells and pores nearly in the same way as natural saccharine
vegetable matter.
If the saccharine solutions such as molasses, starch sugar or sweet-mash are
rendered impure by salts in solution, coloring matter, dextrine, albuminous
matter etc., these impurities will also be absorbed into the cells and pores of the
said substance.
When, by means of hot and strong alcohol the sugar is extracted from the solid
sacchariferous substance which has thus been to a certain extent reconstructed,
I have found, that as in the case of beetroot-sugar, the extract contains no
appreciable quantity of the said impurities, which are not soluble in hot strong
alcohol, or are not dissolved as easily or as soon as the sugar. The separation of
the sugar from the non-saccharine matter, which forms the object of the invention,
is thus mainly effected as also the recovery of the former.
•
If however the saccharine solutions are highly charged with salts, for instance
in the case of ordinary beetroot, and colonial molasses, the greater portion of these
salts can be separated in the form of sulphates, essentially by Marguerite's method
(vid. Stammer's Annual Report Volume 9, page 318 and following, also Vol. 12,
P. 218 and following) which, however for the special object in question, has had to
be altered and improved in some important points.
I shall now illustrate the process derived from the foregoing observations,
describing as an example, the extraction of sugar from raw beetroot molasses by
means of sawdust.
I commence with the process of separating the salts in the form of sulphates,
being an operation not necessarily indispensable but nevertheless useful in
extracting the sugar from molasses.
I. The separation of the salts in the form of sulphates.
According to "Marguerite" the sulphates are separated from the molasses first,
by concentrating the latter to 47 or 48° Beaumé and then adding to them about
the same quantity of alcohol of 85% thoroughly mixed with 4 to 5% of
sulphuric acid of 66° Beamé.
The separation of the sulphates thus formed and the other impurities mechanically
mixed with the molasses from the still very impure, dark brown saccharine solution
is effected by filtering presses under a pressure of 5 to.6 atmospheres.
The process carried out in this way has however, several disadvantages.
a) The sulphates are held in very fine suspension in the saccharine solution.
By using the ordinary filtering: apparatus (pressing-cloth, felt-cloth .etc).and the

page_text: '
high pressure recommended by Marguerite, a considerable portion of these salts
passes through the meshes of the filtering material and as before render the
saccharine solution unnecessarily impure.
b) Notwithstanding the strong pressure, solid cakes are not obtained in the
filtering presses, (see Stammer Vol 12, P. 282,) but only a slimy residuum, so that
a complete separation of the solution from the substances held in suspension does
not take place, which causes some loss of sugar and alcohol.
c) The wear and tear of the filtering cloths is very considerable, as they are
greatly affected by the juices. In order to avoid these disadvantages, I proceed
as follows:
1st Instead of alcohol of 85% strength I only employ alcohol of 50 to 60%
for thinning the molasses, or an equivalent quantity of alcohol of about 90% and
water, mixing it thoroughly by stirring with a quantity of ordinary sulphuric acid
corresponding at the utmost to the quantity of salts contained in the molasses.
This quantity can be easily determined by a preliminary experiment and had
better be rather bare than in excess. The quantity of diluted alcohol can then be
greater than the quantity of molasses. An equal quantity will, however, suffice
to dissolve completely the sugar contained in the molasses. The thinner the
solution, the more easily is it filtered; still it must not be too much reduced, since,
in another stage of the process, thicker masses will be required, thus causing
unnecessary work,
Marguerite, who tried to obtain the sugar from the solution by crystallisation out
of strong alcohol after adding 95% of alcohol and considerable quantities of ground
crystallised sugar, could not, of course, use alcohol of such a low grade. Even in
50 to 60% alcohol the sulphates are mostly insoluble, and the small quantities,
which may be dissolved, are retained in the sawdust, when the latter is extracted
(vid III).
By my process I can easily employ the alcohol recovered by distillation without
having it rectified. The preliminary inspissation of the molasses is avoided in my
process. The sulphates are formed immediately and are gradually deposited as
soon as the stirring apparatus is at a standstill.
2nd For the filtration of the juices amongst which the impurities are distributed
in very fine and slimy particles, a peculiar filtering material is required, and this
may consist of very uniform pieces of chamois-leather, which are inserted in the
frames of the filtering presses or grooves or are employed as filtering hose.
It is known, that fluid can penetrate chamois leather. The latter however,
possesses this quality in a different sense to the usual above named filtering
materials. The leather, in the first instance, becomes saturated and then, according
as on the underside water or other fluid runs off, it eagerly imbibes fresh pure
fluid from the mass to be filtered, without taking up in its pores the smallest
undissolved particles or allowing them to penetrate, as is the case with pressing-
cloths, felt etc. On the contrary, a pure superficial filtration takes place, and in
this process it is complete and excellent. On cutting through the leather, which
has filtered very dirty and slimy fluids, it will be found interiorly clean and at the
most dyed with colouring matter, while the solid particles have settled on the
upper surface.
It is, therefore, much easier to cleanse and use again the chamois-leather than
the pressing and filtering cloths, and moreover, there is a considerable advantage.
in the durability of this material and its resistance to weak acid fluids.
The sulphates form excellent manure.
The excess of sulphuric acid found in the saccharine solution after filtration is
neutralized by hydrate of lime..
II. The treatment of saccharine solutions with sawdust and other fibrous sub-
stances.
Since the sugar must be extracted from the mixture of saccharine solution and
(sawdust by means of hot alcohol, it is necessary, in the first place, to remove the

page_text: élements of the wood, which could be soluble in alcohol, by extracting them by
means of hot alcohol.
The material so treated can be often again employed in future operations. So
much of, the sawdust etc. is now thoroughly mixed with the saccharine solution
under treatment until the whole feels almost dry, soft powder.
The quantity of the saw-dust is, of course, regulated by the strength of the
saccharine solution.
When sulphates were separated from the molasses according to operation I, it
has been found advantageous to thicken the liquor by evaporating the alcohol and,
eventually by boiling down to about 35-40° Beaumé. If the sawdust is mixed at
an ordinary temperature, all the molasses will not penetrate the pores and cells;
on the contrary, a certain quantity, though it may be small, will adhere to the
surface of the vegetable particles. The final product after operation III would at
length bé rendered impure by the non-saccharine substances contained in these
molasses. It is, therefore, desirable to reduce these molasses to the smallest possible
quantity or to remove them. For the former purpose it is advisable to heat the
molasses, while the sawdust is being added.
In this case the absorption of the saccharine solution together with its impurities
takes place in a very complete mauner, so that the sawdust retains on its surface
only small, insignificant quantities of the impurities. Before the following opera-
tion, hot alcohol may be allowed to flow over the molasses powder, and the molasses
either recovered by distillation from this alcohol, which has only washed the
molasses mechanically, or, better still, the alcohol may be utilized in the above
operation I for the separation of sulphates from a fresh quantity of molasses.
III. Extraction of the sugar. In the solid reconstructed sacchariferous material
we have in each case the most important quantities (technically speaking) of the
saccharine contents of the sugar-syrup, as well as the non-saccharine substances
which are held in solution.
The same can be extracted by hot strong alcohol (I prefer it about 80 to 90%
Tralles; for starch sugar solutions, in which only dextrin has to be eliminated,
alcohol of 60 to 70% will suffice) in the way of ordinary lixiviation, as in the
case of beetroot or other solid sacchariferous bodies, while the non-saccharine sub-
stances absorbed into the cells are not carried off by the strong alcohol. Of course,
according to the strength of the hot alcohol, the process of lixiviation must be
continued and repeated until complete exhaustion (see Scheibler's tables in the
Journal of the (German) Society for Beetsugar Industry, volume XXII, page 246).
Many kinds of apparatus are known for the lixiviation of sugar and for recovering
and utilizing the alcohol again.
The extraction-apparatus, supplied for some time past by Wegelin and Hübner
of Halle, may be employed, but of course, other kinds are equally applicable, such
as diffusion batteries and the extraction-apparatus of Häing or Hart (see German
Patents N° 18922 and 19185).
The extraction of the sugar from the alcoholic solution presents no new feature
and, therefore, calls for no further remark.
Lastly, it is known that the alcohol recovered by evaporation and inspissation
can be again utilized for the extraction of saccharine substances.
It will be seen, that this process pure and simple is not claimed as being new,
only its application to solid sacchariferous vegetable substances, which have been
artificially transformed, and also from the fact, that the non-saccharine substances
remain bebind.
IV. The saw dust remaining in the extraction vessel contains the non-saccharine
substances and a remnant of alcohol.
If the sawdust is boiled in water, and filtered, there will be obtained the sub-
stances, which are soluble in water but insoluble in alcohol, and the remainder of
the alcohol. The sawdust is then dried (best and quickest in a vacuum-pan) and
can then be used again.

page_text: t
Having now particularly described and ascertained the nature of my said
Invention and in what manner the same is to be performed, I declare, that what
I claim, is
1st The process of transforming impure saccharine solutions, such as molasses,
starch-sugar solutions and sweet-mash, into a solid sacchariferous substance by
mixing the same with sawdust or other reduced vegetable matter, which absorbs
the solution into the pores and cells for the purpose of obtaining a solid sachari-
ferous material adapted to yield sugar.
2nd The preparation of the sawdust or other reduced vegetable matter for the
absorption of impure saccharine solutions with a view to extracting sugar from
them, and consisting in separating by means of hot alcohol the elements which are
soluble in alcohol.
3rd The lixiviation of the sugar by means of hot strong alcohol, from the solid
sacchariferous vegetable substance reconstituted by mixing impure saccharine
solutions, such as molasses, starch-sugar solutions or sweet mash with reduced
wood or other fibrous substance, the non-saccharine elements remaining behind.
4th In Marguerite's process for the separation of sulphates from the molasses, the
improvement therein obtained by treating unconcentrated molasses with a mixture
of alcohol and water of 50 to 60 degrees, instead of inspissating the molasses to
47-48° Beaume and employing alcohol of 85 %
'
5th The employment of chamois leather as a filtering medium for saccharine
solutions in which solid bodies are suspended in very fine particles or in the form
of slime.