Year: 1887

page_text: Date of Application, 23rd June, 1887
Complete Left, 23rd Mar., 1888
Complete Accepted, 23rd July, 1888
I, GEORGE TALL of 5 Gladstone Avenue of Chester, in the County of Chester, Cake,
Oil and Seed Broker, do hereby declare the nature of this invention to be as follows:-
At present cotton seed oil is deprived of its colouring matter by means of caustic
alkali. By this means a variable amount, say 7 per cent. of the oil is lost in the
mucilage.
Now my invention is designed to prevent this waste, and to make a more perfectly
refined oil, and consists in using a carbonated instead of a caustic alkali and other
improvements and details herein set forth.
My process as at present experimentally carried on by me is as follows:-
To one pint of crude cotton seed oil, I add half a pint of pure water, boil and agitate
the two together and add about one ounce of washing soda and continue boiling and
agitating for about 30 minutes, until the crude oil is well struck and becomes a light
colour. It is then allowed to settle, the oil run into a washing tank and again boiled
and agitated with lime water until it arrives at the colour required. It can then be
brightened by acid unless required for eating purposes.
If for the latter use, it
is separated by decantation and washed with pure water, then boiled till it becomes
bright.
I have mentioned washing soda as the cheapest and therefore best salt for the
purpose, but other salts that will combine with the colouring matter and be soluble in
water and not in oil will do, and in some countries others of these, (monocarbonate of
potash for instance) may be cheaper than washing soda.
WM. P. THOMPSON & Co.,
Of 6, Lord Street, Liverpool,
Agents for the Applicant.

page_text: COMPLETE SPECIFICATION.
Improvements in the Manufacture or Purification of Cotton-
seed Oil.
1, GEORGE TALL of 5 Gladstone Avenue, in the City of Chester, Oilcake and Seed
Broker, do hereby declare the nature of this invention and in what manner the same
is to be performed, to be particularly described and ascertained in and by the following
statement:
At present, cottonseed oil is deprived of its colouring matter by means of caustic
alkali. By this means a variable amount, say from three to seven and a half per cent.
of the oil, is lost in the mucilage. This matter that is lost too, is mostly stearine,
which is the most valuable part of the oil. This mode of depriving the oil of its
colouring matter further gives a disagreeable taste to the oil so that it cannot be used
for food purposes without very expensive treatment.
Now my invention is designed to counteract this waste, and to make a more perfectly
refined oil and consists mainly in using a solution, which will combine with the
colouring matter, but not with the oil, and that will therefore take the colouring
matter from the oil, instead of caustic soda, which forms a soap with a portion of the
oil, and carries down with it or absorbs the colouring matter, leaving the rest of the
oil clear; I prefer for this purpose a solution of monocarbonate of soda or bleaching
powder. The invention also consists in other improvements and details hereinafter
set forth.
My process as at present experimentally carried on by me is as follows:-
To one pint of crude cottonseed oil I add half a pint of pure water and boil and
agitate the two together adding about one ounce of washing soda, or in place of this I
nay dissolve the washing soda in the water before adding it to the oil. I continue
the boiling with constant agitation for about thirty minutes until the crude oil has
become a light colour. It is then allowed to settle, and the brown liquor drawn off.
I then adopt one of the following two methods :-I either renew the process with a
second dose of carbonated alkali water and agitate a second time until almost all of
the remaining colour has been withdrawn from the oil, or I add lime water and agitate
a second time, until the oil arrives at the colour required. Instead of lime water I
can use, however, a bleaching agent such as a hypochlorite, but with all the bleaching
agents which I have tried so far, a disagreeable taste is left in the oil, which is greatly
to be deprecated, and almost entirely precludes its use for culinary purposes, I
therefore prefer to use lime water. The lime water should be somewhat milky with
free lime, and about equal in bulk to the oil. If it be found that there is not sufficient
lime, a little more can be added to the lime water during the operation.
When the oil has arrived at the desired colour the whole is allowed to settle again,
and the lime-water run off, when, if the oil be not required for food, it is brightened
by the addition of a little very dilute sulphuric acid, aspirated over its surface by
means of an aspirator or rose. This acid in falling through the oil, withdraws the
residual lime, which may be present. If, however, the oil has to be used for any

page_text: eating purpose, it is well washed with pure cold water, and then heated with the water
to the boiling point of the latter, and the boiling continued till the oil becomes bright.
Since taking out the provisional specification, further discoveries have been made
which form the subject of a fresh patent application taken out in the names of myself
and that of my patent agent, who assisted me in their discovery, No. 15647 of 1887.
This second application is for improvements useful mainly for oils for eating purposes,
and consists in treating the oil (after it has been agitated with the alkaline carbonate
solution and separated therefrom), by agitation with dessicated fuller's earth or other
like material to separate the remaining colouring matter and taste, instead of or in
addition to using lime. Each process has its advantages, and I merely mention the
second process to prevent any question being raised against the validity of this patent
on the ground that I had kept back information known to me which, under some
circumstances, might be useful.
I have only mentioned monocarbonate of soda, I find, however, that monocarbonate
of potash, and to some extent some other salts with an alkaline reaction, will perform
the action. All of these are, however, more expensive than monocarbonate of soda,
and possessing no counterbalancing advantage over the latter, it is needless to specify
them.
Having now particularly described and ascertained the nature of the said inven-
tion, and in what manner the same is to be performed, I declare that what I
claim is :-
1. The improvement in the manufacture or purification of cottonseed oil, which
consists in separating the colouring matter therefrom, by agitating the crude oil with
a solution of monocarbonate of soda, or other salt, capable of dissolving the colouring
matter without combining with, being dissolved in, or deleteriously acting upon the
oil, substantially as described.
2. In combination with the matter of claim 1, the remaining steps in the process of
purifying the cottonseed oil, substantially as herein set forth.
Dated this 22nd day of March 1888.
WM. P. THOMPSON & Co.,
Of 6, Lord Street, Liverpool,
Patent Agents for the Applicant.