AN IMPROVED METHOD OF SEPARATING GLYCERINE FROM SALINE AND OTHER SUBSTANCES
Year: 1858

page_text: LETTERS PATENT to Henry Reynolds, of King William Street, in the,
City of London, Gentleman, for the Invention of "AN IMPROVED METHOD
OF SEPARATING GLYCERINE FROM SALINE AND OTHER SUBSTANCES."
Sealed the 7th December 1858, and dated the 10th June 1858.
PROVISIONAL SPECIFICATION left by the said Henry Reynolds at the
Office of the Commissioners of Patents, with his Petition, on the 10th
June 1858.
I, HENRY REYNOLDS, of King William Street, in the City of London,
Gentleman, do hereby declare the nature of the said Invention for "AN
IMPROVED METHOD OF SEPARATING GLYCERINE FROM SALINE AND OTHER SUBSTANCES,"
to be as follows:-
It is well known that spent soap lees generally contain glycerine mixed
with some free and carbonated alkali, common salt, and several other
impurities, and that by the ordinary method the glycerine is separated in a
fair state of purity by saturating the alkali and carbonates with their equi-
valents of sulphuric acid; and after evaporating the liquor almost to dryness,
dissolving out the glycerine by means of alcohol, which alcohol is again.
separated by distillation.
Now I have ascertained by numerous experiments that glycerine may be
obtained from spent soap lees and other fluids containing glycerine mixed

page_text: with saline and other substances much more economically, and in an equal or
greater state of purity than heretofore, by means of a current of dry steam at
a temperature of about 400° Fahr., either blown on to the spent soap lees or
through them. The fluid may be first reduced by evaporation, and raised
nearly to the boiling point by being passed through a heated still-like vessel,
or by being heated in any other convenient vessel. It is then passed into
another vessel where it is met by a jet or jets of superheated steam, which
raises it to the boiling point and evaporates the glycerine, carrying the vapour
upwards with it, and leaving the salts to deposit themselves in the vessel. If
greater purity is required it may be obtained by repeating the process, and the
little colour that remains can easily be removed in the ordinary manner by
animal charcoal or chlorine.
I do not limit myself, however, to the method of proceeding herein-before
described, as the aforesaid fluids may be treated with dry or superheated
steam by many other methods, and it is in the extraction of glycerine from
such fluids by means of dry or superheated steam that my Invention essentially
consists.
SPECIFICATION in pursuance of the conditions of the Letters Patent, filed
by the said Henry Reynolds in the Great Seal Patent Office on the
10th December 1858.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, HENRY
REYNOLDS, of King William Street, in the City of London, Gentleman, send
greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her Letters
Patent, bearing date the Tenth day of June, in the year of our Lord One
thousand eight hundred and fifty-eight, in the twenty-first year of Her reign,
did, for Herself, Her heirs and successors, give and grant unto me, the said
Henry Reynolds, Her special licence that I, the said Henry Reynolds, my
executors, administrators, and assigns, or such others as I, the said Henry.
Reynolds, my executors, administrators, and 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 "AN IMPROVED METHOD OF
SEPARATING GLYCERINE PROM SALINE AND OTHER SUBSTANCES," upon the condition
(amongst others) that I, the said Henry Reynolds, my executors or adminis

page_text: trators by an instrument in writing under my, or their, or one of their hands
and seals, should particularly describe and ascertain the nature of the said
Invention, 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 Henry Reynolds, do hereby declare the
nature of my said Invention, and in what manner the same is to be per-
formed, to be particularly described and ascertained in and by the following
statement thereof, that is to say:-
It is well known that spent soap lees generally contain glycerine mixed
with some free and carbonated alkali, common salt, and several other
impurities, and that by the ordinary method the glycerine is separated in a
fair state of purity by saturating the alkali and carbonates with their equi-
valents of sulphuric acid, and, after evaporating the liquor almost to dryness,
dissolving out the glycerine by means of alcohol, which alcohol is again
seperated by distillation.
Now I have ascertained by numerous experiments that glycerine may be
obtained from spent soap lees and other fluids containing glycerine mixed
with saline and other substances much more economically and in an equal or
greater state of purity than heretofore, by means of a current of dry steam at
a temperature of about 400° Fahrenheit, either blown on to the spent soap
lees or through them. The fluids may be first reduced by evaporation, and
raised nearly to the boiling point by being passed through a heated still-like
vessel, or by being heated in any other convenient vessel. It is then passed
into another vessel, where it is met by a jet or jets of superheated steam which
raises it to the boiling point and evaporates the glycerine, carrying the vapour
upwards with it, and leaving the salts to deposit themselves in the vessel. If
greater purity is required it may be obtained by repeating the process, and the
little colour that remains can easily be removed in the ordinary manner by
animal charcoal or chlorine.
I do not limit myself, however, to the method of proceeding herein-before
described, as the aforesaid fluids may be treated with dry or superheated
steam by many other methods, and it is in the extraction of glycerine from
such fluids by means of dry or superheated steam that my Invention essentially
consists.
I now proceed to describe the manner in which I carry my Invention into
effect. My especial object is the separating of glycerine from the several sub-
stances with which it is usually found mixed in the "spent lees" of the soap-
maker, when the manufacture has been carried on with soluble caustic alkalies

page_text: and neutral fat acids; and the procuring of the glycerine in a state of purity
or freedom from saline and other substances.
The means by which I proceed to separate the glycerine from the impurities
with which it is mixed in ordinary "spent soap lees," is to evaporate the spent
soap lees in an open or partially closed vessel by means of an open fire or steam
applied in any ordinary manner, but I prefer to carry on the first part of the
process, viz. the evaporation of a large portion of the water of the spent soap
lees, by means of a coil or any other convenient form of steam pipes placed in
the evaporating vessel at a few inches, say three or four, from the surface of
the evaporating fluid, as I find that by so placing the steam pipes, evaporation
takes place more rapidly and with a considerable saving of fuel. As the salts
which are always found in solution in spent soap lees deposit at the bottom of
the evaporating vessel, I remove them from time to time by means of rakes or
other convenient tools, and throw them into a drainer, returning the fluid that
drains from them into the evaporating vessel. I maintain the level of the
evaporating fluid at one constant point by means of a supply cistern regulating
.the flow by a ball cock or floating valve. When I find that the fluid has
arrived at its greatest density as regards the contained quantity of glycerine,
which I judge of by its boiling point being about 240° Fahrenheit, and not by
its actual density, as shown by a hydrometer, I transfer it to a still, or the
evaporation may be carried on altogether in a still, but I do not find that
mode so convenient or economical. When the fluid is in the still, I raise the
.temperature on the surface, or for a few inches in depth from its surface, to
about 380° Fahrenheit, and when at this temperature I direct a current of
ordinary high-pressure or superheated steam through the upper stratum of the
hot fluid, regulating the temperature of the injected steam until I find that
the glycerine is blown over free from acroleine, into which it may become
.converted if the temperature is too high.
It is not easy to define the exact temperature at which the glycerine
separates from its combination with the several salts, resin, soaps, and other
.matters with which it is mixed in the spent soap lees, as scarcely two samples
of spent soap lees are alike, yet there is no practical difficulty in the conduct
of the operation of distillation, if the injected steam is thrown in at about 400°
Fahrenheit, the fluid to be distilled being at a temperature of about
380° Fahrenheit, and the temperature of the steam being gradually raised or
.lowered or maintained according as water, glycerine, or acroleine is formed to
.be present in the condenser of the still, the glycerine being detected by its
.sweet taste, the acroleine by its peculiar pungent smell. For many reasons I
prefer to use a still so arranged as to heat the fluid only at the upper surface,

page_text: as I find there is less expenditure of fuel, the temperature is more easily
regulated, and as means are provided to maintain a constant level of the fluid
in the still, the operation of distillation need only be stayed when the body of
the still becomes fitted with the salts and other substances, besides glycerine
contained in the spent soap lees.
It is not necessary to employ a still of the above nature, as I have succeeded
in separating glycerine from its saline combination as found in spent soap
lees, by means of an ordinary superheated steam still, as is well understood
and used for the distillation of the fat acids by the makers of "stearine."
And having now described the nature of my said Invention, I declare that
I claim the separation of glycerine from the saline and other matters with
which it is usually found associated in the spent lees of the soap-maker, by
the means and in manner herein-before described.
In witness whereof, I, the said Henry Reynolds, have hereunto set my
hand and seal, this Eighth day of December, One thousand eight
hundred and fifty-eight.
HENRY REYNOLDS. (L.s.)