AN IMPROVED MODE OF AND MEANS FOR CLARIFYING SACCHARINE SOLUTIONS
Year: 1867

page_text: PROVISIONAL SPECIFICATION left by William Robert Lakė at the
Office of the Commissioners of Patents, with his Petition, on the
30th November 1867.- A communication from abroad by Joseph
Edward Freund, of the City and State of New York, United States of
America,
I, WILLIAM ROBERT LAKE, of the "International Patent Office," No. 8,
Southampton Buildings, Chancery Lane, in the County of Middlesex,
Consulting Engineer, do bereby declare the nature of the said Invention for
"AN IMPROVED MODE OF AND MEANS FOR CLARIFYING SACCHARINE SOLUTIONS,"
a communication, to be as follows:-
is
In the ordinary process of sugar refining the raw or muscavado sugar.
dissolved in water and the solution treated with blood and lime, by which,
when subjected to the action of heat a portion of the impure foreign matter
is coagulated into a thick scum which is skimmed off by hand. The clarified
solution is usually passed through flannel or felt to separate the sediment or
impurities that may be mechanically suspended in the liquid, and then passed
through bone black filters preparatory to being concentrated in the pans and
subsequently granulated or crystallized in moulds. The function performed
by the bone black is not only to decolorize the liquor but to separate and
retain the salts with which it is as intimately combined as with the sugar for

page_text: which it is treated. It is in many cases considered necessary to employ a
thickness of forty feet of this bone black, and the filters must be heated or the
solution used when hot to facilitate the passage of the liquor. When removed
from the filters and renovated by reburning or otherwise, the bone black must
be carefully sifted to separate the fine dust which would otherwise clog the
filter and into which a large portion of it is reduced by the attrition consequent
upon the necessary and repeated handling. When it is considered that in
making the highest grades of sugar a ton of bone is used to a ton of sugar, it
may readily be appreciated that a large proportion of the cost of production
consists not only in the cost of the bone, but in the expense of re-burning and
handling and the waste of the dust. In consequence of these considerations
many efforts have been made to procure a more perfect clarifying agent or
defecator than bullock's blood, which is expensive, and must necessarily be used
in practise in a partially putrid and otherwise filthy condition. Instead of
the albumen of blood that of eggs has been used, the coagulation of which
includes to a great extent the other foreign matters of the solution, but the
obvious objection is the still greater expense. Chemical substances have also
been proposel, as the basic acetate of lead for instance, but the removal of the
pois: nous material has been as difficult and costly as the removal of the
original impurities, which moreover, although more apparent to the eye possess
the important advantage of not being deleterious to the health.
The object of my Invention therefore is to obtain a clarifier or defecating
agent which shall be cheap, simple to use, readily and plainly tested, and not
detrimental to health when used to excess; and which in addition shall be
so perfect in its action that the expense attendant upon the use of bone black
may be largely lessened. For this purpose, when a solution of raw sugar or
molasses has been made in lime water I employ the neutral sulphate of alumina
by which the coloring and other foreign matter is precipated and aggregated
into a mass that is thrown to the surface by the application of heat, whence it
may be removed by skimming or other appropriate means; heat is not
absolutely necessary, but it facilitates and developes the operation more perfectly.
The affinity of alumina and its compounds for vegetable coloring matter has
not only occasioned their use in the preparation of pigments, but the peculiar
attraction which they possess for fibres of cotton, silk, and wool have rendered
them of great importance as mordants in the arts of dyeing and printing cloths.
In the application of the neutral sulphate of alumina to the manufacture and
refining of sugar, the presence of lime seems to occasion the abstraction of
'the acid and the formation of the comparatively insoluble sulphate of lime,
which becomes intermixed with the alumina and would be precipitated with

page_text: it if it were not for the fibrous and other foreign matter which the latter bas
segregated from the mass, and, with which, in a heated saccharine solution,
it rises to the surface. The dissolution of the sugar in the lime 'water to
make a complete and uniform blending of the lime and sugar, or a formation
of a sucrate of lime and the subsequent use of the alumina in a finely divided
condition, ensures that the re-action between the lime and the alumina shall
include every particle of the sugar.