IMPROVEMENTS IN THE MANUFACTURE OF SUGAR, AND IN PURIFYING SACCHARINE SOLUTIONS
Year: 1874

page_text: LETTERS PATENT to John Stenhouse, of Rodney Street, Pentonville,
in the County of Middlesex, Analytical Chemist, for the Invention
of "IMPROVEMENTS IN THE MANUFACTURE OF SUGAR, AND IN PURIFYING
SACCHARINE SOLUTIONS."
Sealed the 17th April 1874, and dated the 20th February 1874.
PROVISIONAL SPECIFICATION left by the said John Stenhouse at the
Office of the Commissioners of Patents, with his Petition, on the
20th February 1874.
I, JOHN STENHOUSE, of Rodney Street, Pentonville, in the County of
3 Middlesex, Analytical Chemist, do hereby declare the nature of my
said Invention for "IMPROVEMENTS IN THE MANUFACTURE OF SUGAR, AND IN
PURIFYING SACCHARINE SOLUTIONS,” to be as follows:-
This Invention relates to the treatment of sugar, or of saccharine
solutions, containing lime, either in the form of saccharate of lime or
otherwise, and consists in effecting the removal of the lime contained
in solutions of sugar or other saccharine solutions by means of oxalic
acid, or by means of oxalate of ammonia, or of oxalate of potash, or of
oxalate of soda, or of mixtures of the same.

page_text: In carrying out my Invention sugar previously dissolved in water or
other saccharine solutions, either hot or cold, containing lime are to be
submitted to the action of oxalic acid, or of the oxalates before referred
to, or of mixtures of the same, by preference in solution, and in such
quantity as that the whole or practically the whole of the lime shall be
precipitated in the form of oxalate of lime, care being taken that no excess
of oxalic acid or of the oxalates be employed; the precipitated oxalate
of lime may by subsidence and filtration be separated from the saccharine
solutions.
The greater portion of the oxalic acid contained in the oxalate of lime
resulting from the above described process can, as is well known, be
recovered by digesting the precipitate after it has been well washed
with sulphuric acid in the manner usually employed for preparing oxalic
acid from oxalate of lime. This oxalic acid if desired can of course be
used over again for purifying saccharine solutions.
SPECIFICATION in pursuance of the conditions of the Letters Patent,
filed by the said John Stenhouse in the Great Seal Patent Office
on the 17th July 1874.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, JOHN
STENHOUSE, of Rodney Street, Pentonville, in the County of Middlesex,
Analytical Chemist, send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her Letters
Patent, bearing date the Twentieth day of February, in the year of our
Lord One thousand eight hundred and seventy-four, in the thirty-
seventh year of Her reign, did, for Herself, Her heirs and successors,
give and grant unto me, the said John Stenhouse, Her special license
that I, the said John Stenhouse, my executors, administrators, and
assigns, or such others as I, the said John Stenhouse, my executors,
administrators, or assigns, should at any time agree with, and no others,
from time to time and at all times thereafter during the term therein
expressed, should and lawfully might make, use, exercise, and vend,
within the United Kingdom of Great Britain and Ireland, the Channel
Islands, and Isle of Man, an Invention for "IMPROVEMENTS IN THE MANU-
FACTURE OF SUGAR AND IN PURIFYING SACCHARINE SOLUTIONS," upon the con-
dition (amongst others) that I, the said John Stenhouse, my executors

page_text: or administrators, by an instrument in writing, under my hand and seal,
should particularly describe and ascertain the nature of the said In-
vention, and in what manner the same was to be performed, and cause
the same to be filed in the Great Seal Patent Office within six calendar
months next and immediately after the date of the said Letters
Patent.
NOW KNOW YE, that I, the said John Stenhouse, do hereby declare
the nature of my said Invention, and in what manner the same is to be
performed, to be particularly described and ascertained in and by the
following statement, that is to say:-
This Invention relates to the treatment of a solution of sugar, or of
saccharine solutions, containing lime, either in the form of saccharate of
lime, or otherwise, and consists in effecting the removal of the lime
contained in solutions of sugar, or in other saccharine solutions, by
means of oxalic acid, or by means of the oxalates of ammonia, or of the
oxalates of potash, or of the oxalates of soda, or of mixtures of the same.
In carrying out my Invention sugar previously dissolved in water or
other saccharine solutions, either hot or cold, containing lime are to be
submitted to the action of oxalic acid, or of the oxalates before referred
to, or of mixtures of the same, by preference in solution, and in such
quantity as that the whole or practically the whole of the lime shall be
precipitated in the form of oxalate of lime, care being taken that no
excess of oxalic acid or of the oxalates be employed; the precipitated
oxalate of lime may by subsidence or by filtration be soparated from the
saccharine solutions.
I have found in practice that it is more advantageous to employ a
mixture of oxalic acid, and of one or more of the oxalates, by preference
the oxalate of ammonia. And I have also found that in treating such
before-mentioned solutions of sugar or saccharine solutions that oxalic
acid in conjunction with about one fourth of the oxalate of ammonia by
weight gives satisfactory results.
In order to prevent the possibility of any free oxalic acid, or of the
oxalates remaining in the solutions of sugar, or in the saccharine
solutions which have been treated as before mentioned, I prefer to
submit the same after such treatment to the action either of a solution
of bicarbonate of lime or to carbonate of lime in a finely divided and
suspended condition,

page_text: The greater portion of the oxalic acid contained in the oxalate of
lime resulting from the above-described process can, as is well known,
be recovered by digesting the precipitate after it has been well washed
with water with sulphurated acid in the manner usually employed for
preparing oxalic acid from oxalate of lime. This oxalic acid if desired
can of course be used over again for purifying solutions of sugar or
saccharine solutions.
Having now described and particularly ascertained the nature of my
said Invention, and the manner in which the same is or may be used or
carried into effect, I would observe in conclusion that what I consider to
be novel and original and therefore claim as the Invention secured to me
by the herein-before in part recited Letters Patent is, effecting the
removal of lime contained in solutions of sugar, or in saccharine
solutions, either in the form of saccharate of lime or otherwise, by the
employment of oxalic acid, or of the oxalates of ammonia, or of soda,
or of potash, or of mixtures of the same.
In witness whereof, I, the said John Stenhouse, have to this my
Specification set my hand and seal, this Fifteenth day of July,
One thousand eight hundred and seventy-four.