Improvements in Obtaining Fatty Acids and Glycerine from Fats and Oils.
Year: 1888

page_text: Date of Application, 21st Apr., 1888
Complete Specification Left, 17th Jan., 1889
Complete Specification Accepted, 23rd Feb., 1889
PROVISIONAL SPECIFICATION.
Improvements in Obtaining Fatty Acids and Glycerine from Fats
and Oils.
I, JULIUS LEWKOWITSOH, Ph.D., F.L.C., F.C.S., of 6 Warwick Place, Leeds,
in the County of York, do hereby declare the nature of this invention to be as
follows:-
Of the different processes, which have been devised for the saponification of fats
and oils with a view of simultaneously recovering the glycerine, those which are
performed by means of water or steam are the only processes which ensure both the
entire absence of mineral matters and the greatest purity of the fatty acids and of
the glycerine. The processes which have been based on the decomposition of fats
and oils by means of water involve in consequence of the high pressure required
a great deal of technical difficulties, which prevent their being generally adopted.
The same holds good of the process of saponification by means of superheated steam
as patented by Messrs. Wilson & Payne (July 24th 1854) inasmuch as the
temperature, besides being a very high one, has to be closely watched and to be kept
within very narrow limits at about 600° F.; if the temperature falls much below
that point, the decomposition takes place ac too slow a rate, or in case of the
temperature rising above 600° F. destruction of glycerine follows with the formation
of the most objectionable acroleïne.
The object of my invention is to decompose fats or oils by distilling the same with
superheated steam in "vacuo." I heat the fats or oils moderately in a suitable
still by a slow fire, raise the temperature by introducing superheated steam to about
400° F. and create now by means of a vacuum-pump or a steam injector-pump
a ininus pressure of 10 to 13 lbs., when the decomposition of the fats or oils takes
place readily and the fatty acids and the glycerine distil over. They are caught in
suitable receivers which admit of being emptied, so that the minus pressure may be
kept up in the still. The temperature may be allowed to rise, without the least
inconvenience to 460° F. or higher, when it is reduced by a constant supply of fresh
fat or oil admitted into the still. The fatty acids and the glycerine thus obtained are
worked up by known processes.

page_text: The superiority of my process to those mentioned above is evident.
The process can be carried out at a comparatively low heat and it is not necessary
to watch the temperature with extreme care; in fact it may be allowed to vary
within wide limits, the quickness of the distillation depending less on the high
température than on the height of the underpressure. If the temperature should
rise too high, it can easily be regulated by a fresh feed of fat or oil introduced into
the still, without it being required to alter the fire. Furthermore there is a great
deal of saving of steam and fuel, as the supply of steam may be a very moderate one,
whereas in the process hitherto known a most plentiful supply of steam was to be
kept up. Lastly the products obtained are very pure indeed, as no destructive
distillation takes place at the above mentioned tomperature; it is especially worth
mentioning that not the slightest decomposition of the glycerine is to be noticed.
Dated this 21st day of April 1888..

page_text: COMPLETE SPECIFICATION.
Improvements in Obtaining Fatty Acids and Glycerine from Fats
and Oils.
I, JULIUS LEWKOWITSCH Ph.D., F.I.C., F.C.S., of 6 Warwick Place, Leeds, in
the County of York, 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 :-
:
Of the different processes, which have been devised for the saponification of fats
and oils with a view of simultaneously recovering. the glycerine, those which are.
performed by means of water or steam are the only ones, which ensure both the
entire absence of mineral matters and the greatest purity of the fatty acids and of
the glycerine. The processes, which have been based on the decomposition of fats
and oils by means of water involve, in consequence of the high pressure required, a
great deal of technical difficulty which prevents their being generally adopted. The
same holds good of the process of saponification by means of superheated steam
as patented by Messrs. Wilson & Payne (July 24th 1854) inasmuch as the
temperature besides being a very high one has to be closely watched and to be
kept within very narrow limits at about 600° F. if the temperature falls below that
point the saponification takes place at too slow a rate whilst in case of the
temperature rising above 600° F. destructive distillation of glycerine sets in with
the formation of that most objectionable substance acroleïne. But even at 600° F.
unless an extremely large excess of steam be used partial decomposition of glycerine
cannot be avoided. In fact the difficulties attending this process have been so great
that it could only be applied to those oils, which are more readily saponified, as
palm oil and cocoa nut oil and even in the last mentioned instances the working of
the patented process has been abandoned.
The object of my invention is to saponify fats or oils by distilling the same with
superheated steam in "vacuo."
I heat the fats or oils in a suitable still by a slow fire protecting the still from
coming into direct contact with the fire or the hot fire gases. By introducing
superheated steam through a perforated coil into the still, I raise the temperature
to about 400° F. which can be read off a thermometer immersed into the fats.
Now by means of any kind of vacuum pump I create in the still a minus pressure
of 10 to 13 lbs. when the saponification of the fats or oils takes place readily and
the fatty acids and the glycerine distill over uncombined. They are condensed in
suitable receivers which admit of being emptied in such a way that the minus pressure
may be kept up in the still.
The temperature may be allowed to rise without the least inconvenience to 460° F.
or coca a little higher when it is reduced by a constant supply of fresh fat or oil
admitted into the still from a store vessel which may stand higher than, or on a
level with the still as the air pressure will force the fat into the still. The feeding
is thus going on regularly and has only to be interrupted when stopping of the work
is intended.

page_text: The fatty acids and the aqueous solution of the glycerine separate according to
their specific gravities and are worked up by known processes.
The superiority of my process to those mentioned above is evident. The splitting up.
of the fats can be carried out without pressure and at a comparatively low temperature,
it is not necessary to watch the temperature with extreme care, in fact it may be
allowed to vary within wide limits, the quickness of the distillation depending
less on the high temperature than on the amount of vacuum or minus pressure. If
the temperature. should rise too high it can easily be regulated by a fresh feed of
fat or oil, without it being required to alter the fire. Furthermore there is a great
saving in the expenses for steam and fuel, as the supply of steam may be a moderate
one, whereas in the processes hitherto known a most plentiful supply of steam had to
be kept up. The saponification of the fats and oils by this process is complete, all
the fats being easily split up into fatty acids and glycerine. The resulting products
are very pure indeed. The fatty acids are colourless and may be used at once for
manufacturing soap and candles. As no destructive distillation takes place the
glycerine does not undergo the slightest decomposition and when boiled down
compares in quality very favorably with the best French "Saponification Glycerine."
Having now particularly described and ascertained the nature of my said inven
tion. and in what manner the same is to be performed I declare that what I
claim is:
1. The heating of fats and oils with superheated steam in vacuo substantially as
described thereby decomposing the same into fatty acids and glycerine which are
carried off by the steam and condensed in suitable receivers.
2. The manufacture of fatty acids suitable for making soap and candles by the
process mentioned in the first claiming clause.
3. The manufacture of glycerine by the process mentioned in the first claiming
clause.
Dated this 16th day of January 1889.