Improvements in the Purification of Syrup, Molasses, and the like.
Year: 1898

page_text: [Communicated from abroad by JOHANNES C. Boor, of Klatten, in the Island of
Java, Dutch East Indies, Engineer.]
Improvements in the Purification of Syrup, Molasses, and the like.
I, WILLIAM PHILLIPS THOMPSON, F.C.S., M.I.M.E., of the Agency for Foreign
Patent Solicitors, 322, High Holborn, in the County of Middlesex, 6, Lord
Street, Liverpool, and 6, Bank Street, Manchester, both in the County of Lan-
caster, and Lower Temple Street, Birmingham, in the County of Warwick, Civil
Engineer, do hereby declare the nature of this invention to be as follows:-
My invention relates to improvements in the decolorization of syrups, molasses,
and vegetable juices, and consists essentially in treating these syrups, molasses,
or vegetable juices with zinc and sulphurous acid, forming hydrosulphurous
acid, and afterwards precipitating the zinc with a soluble ferrocyanide.
In carrying out my invention the syrups, molasses or vegetable juices of a
concentration below 50° Brix are heated to about 50° Centigrade and with con-
stant stirring, zine, and sulphurous acid are added, the liquor is then heated to
a temperature say 80° Centigrade and a soluble ferrocyanide is added till all
the zinc is precipitated.
The liquor is then filtered or decanted in order to free it from the precipitate
of ferrocyanide of zinc.
In order to carry my said process into operation I proceed as follows:-
The syrups, molasses, or vegetable juices are brought to a concentration of
about 400 or 50° Brix in a reservoir provided with stirring apparatus and steam
heater. The temperature must not exceed 50° Centigrade.
By constant stirring, zinc is added in quantities varying from 5 to 25 grammes
per hectolitre and sulphurous acid till strong acid reaction is obtained.
After the decolorization is finished the reservoir is heated at a temperature
ranging from 70°-95° Centigrade and a soluble ferrocyanide is added in order
to precipitate the zinc, the ferrucyanide of zinc is separated from the saccharine
solution in a suitable filter.
The decolorized syrups, molasses or vegetable juices are worked up into sugar
in the usual well known way.
I will add by way of further explanation that I prefer to employ ferrocyanide
of potassium in my process, and that the precipitated ferrocyanide of zinc may be
separated by filter presses, bag filters, suction bags, centrifugal machines, or any
apparatus designed to separate solids from liquids.
Dated this 23rd day of August 1898..

page_text: Improvements in the Purification of Syrup, Molasses, and the like.
I, WILLIAM PHILLIPS THOMPSON, F.C.S., M.I.M.E., of the Agency for Foreign
Patent Solicitors, 322, High Holborn, in the County of Middlesex, 6, Lord
Street, Liverpool, and 6, Bank Street, Manchester, both in the County of Lan-
caster, and Lower Temple Street, Birmingham, in the County of Warwick,
Civil Engineer, do hereby declare the nature of this invention and in what
manner the same is to be performed to be particularly described and ascer-
tained in and by the following statement:-
My invention relates to improvements in the decolorization of syrups, molasses,
and vegetable juices, and consists essentially in treating these syrups, molasses
or vegetable juices with zinc and sulphurous acid, forming hydrosulphurous
acid, and afterwards precipitating the zinc with a soluble ferrocyanide.
In carrying out my invention the syrups, molasses or vegetable juices of a
concentration below 50° Brix are heated to about 50° Centigrade and with con-
stant stirring, zine, and sulphurous acid are added, the liquor is then heated to
a temperature say 80° Centigrade and a soluble ferrocyanide is added till all
the zine is precipitated.
The liquor is then filtered or decanted in order to free it from the precipitate
of ferrocyanide of zinc.
In order to carry my said process into operation I proceed as follows:-
The syrups, molasses, or vegetable juices are brought to a concentration of
about 400 or 50° Brix in a reservoir provided with stirring apparatus and steam
heater. The temperature must not exceed 50° Centigrade.
By constant stirring, zinc is added in quantities varying from 5 to 25 grams
per hectolitre and sulphurous acid till strong acid reaction.
After the decolorization is finished the reservoir is heated at a temperature
ranging from 70°-950 Centigrade and a soluble ferrocyanide is added in order
to precipitate the zinc, the ferrocyanide of zinc is separated from the saccharine
solution in a suitable filter.
The decolorized syrups, molasses or vegetable juices are worked up into sugar
in the usual well known way.
I will add by way of further explanation that I prefer to employ ferrocyanide
of potassium in my process, and that the precipitated ferrocyanide of zinc may be
separated by filter presses, bag filters, suction bags, centrifugal machines, or any
apparatus designed to separate solids from liquids.
I may also treat the saccharine liquids by means of a solution of hydro-
sulphurous acid which has been prepared separately so as to avoid the introduction
in these liquors of injurious products, the removal of which might present
difficulties. The hydrosulphurous acid is preferably prepared by a process
similar to that above described, that is to say, by the addition of zinc to a solution
of sulphurous acid in order to form the hydrosulphurous acid, and subsequent
precipitation of the zinc by means of a soluble ferrocyanide and the separation
by filtration of the precipitated ferrocyanide of zinc. This precipitate may be
further treated by means of an alkaline solution to recover a soluble ferro-
cyanide. In order to carry these operations into effect, the solution of sulphurous
acid is placed in a closed vessel provided with an agitator arranged and operated
in any suitable manner. During the agitation a quantity of zinc is added
proportionate to the quantity of sulphurous acid present, whereupon there is
obtained the reaction:

page_text: There is added afterwards the soluble ferrocyanide to precipitate the zinc
according to the formula:
2ZnSOK(Cy) *Fe
========
Zn (Cy) Fe + 2K SO³
The ferrocyanide of zinc is separated by means of a filter and the soluble
ferrocyanide can be again obtained therefrom by heating it in an alkaline
solution according to the formula:
Zn2(Cy) Fe + 4KOH
=
K(Cy) Fe 2Zn(OH)2
I wish further to remark that I do not confine myself to the use of the hydro-
sulphurous acid prepared according to the process above set forth, but I con-
sider as my invention the decolorization of saccharine liquors by treating them
with hydrosulphurous acid obtained in any suitable manner.
Having now particularly described and ascertained the nature of my said
invention, and in what manner the same is to be performed, as communicated
to me by my foreign correspondent, I declare that what I claim is:-
1. Process for the decolorization of syrups, molasses or saccharine liquids,
characterized by the addition to the said liquids of zinc and sulphurous acid,
the precipitation of the zinc by means of a soluble ferrocyanide and the filtration
of the liquids to separate the precipitate of ferrocyanide of zinc from them,
substantially as described.
2. Process for decolorization of syrups, molasses or saccharine liquids,
characterized by the treatment of the said liquids by means of hydrosulphurous
acid prepared separately by adding zinc to a solution of sulphurous acid, the said
zine being subsequently precipitated by a soluble ferrocyanide and separated in
the form of ferrocyanide of zinc, substantially as described.
3. The improved process for decolorizing saccharine liquids of all kinds con-
sisting in treating the said liquids with solution of hydrosulphurous acid.
TX
1
11
1
1000
W. P. THOMPSON & Co.,
Of London, Liverpool, Manchester and Birmingham.