Improvements in and relating to the Purification of Glycerine.
Year: 1888

page_text: Date of Application, 20th Oct., 1888
Complete Specification Left, 13th July, 1889-Accepted, 17th Aug, 1889
PROVISIONAL SPECIFICATION.
Improvements in and relating to the Purification of Glycerine.
I, JOSEPH C. A. BRUNNER, of Munich (Bavaria), in the Empire of Germany,
Chemist, do hereby declare the nature of this invention to be as follows:-
Heretofore the purification of crude glycerine has been attended with difficulty
and has required much time, in the distilling process, as well as in the treatment
with decolourizing charcoal, and also in the purification by crystallization. I have
succeeded in directly obtaining from crude glycerine by means of the improved
process which forms the subject of this invention a light yellow almost inodorous
product which as regards purity is equivalent to the so-called "refined" glycerine
of commerce.
The following will serve as an example of the said improved process.
To 100 parts of crude glycerine about 8 parts of zinc-vitriol, which may or may
not be roasted, are added, and the mixture is heated; after the cooling of this mixture
about 27 parts of powder of caustic lime are added. These proportions can of
course be varied within certain limits according to the kind of crude glycerine
employed.
It is then only necessary to filter by means of a filter-press in order to obtain at
once a good commodity.
The effect of the reagents, besides that resulting from the property of every
precipitate carrying with it certain impurities, colouring-matters, and the like,
consists in that the fatty acids of the crude glycerine, such as butyric acids and the
like, form with zinc-oxide, lime, and the like, slightly soluble compounds, and are
thus removed.
In this improved process, sulphate of zinc, dissolved in glycerine, forms with
lime, baryta or the like, zinc-hydrate and calcium, barium, or like sulphate the fatty
acids, such as butyric acids and the like, are taken up by the zinc-oxide and form
insoluble salts; the calcium, barium or like sulphate is likewise almost insoluble in
glycerine. A small excess of lime, baryta, or the like, is removed by the blowing in
of carbonic acid under heat, any traces of metal are precipitated by sulphide of
hydrogen, and an excess of sulphide of hydrogen is removed by the blowing through
of air.
The precipitate retained in the filter press is regenerated by means of sulphuric
acid to form sulphate of zinc, and as such it can be used again for the purification ;
the fatty acids are at the same time obtained as a by-product.
It will be understood that, as a matter of course, in lieu of sulphate of zinc other
metallic sulphates, such as sulphate of magnesia, sulphate of alumina, alum, sulphate
of iron, sulphate of copper, or the like; in lieu of lime either carbonate of lime or
baryta ; and in lieu of sulphuric acid oxalic acid can be used.
Dated this 20th day of October 1888.
HASELTINE, LAKE & Co.,
45, Southampton Buildings, London, W.C., Agents for the Applicant.
COMPLETE SPECIFICATION.
Improvements in and relating to the Purification of Glycerine.
I, JOSEPH C. A. BRUNNER, of Munich (Bavaria), in the Empire of Germany,
Chemist 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 :-
:-
Heretofore the purification of crude glycerine has been attended with difficulis

page_text: and has required much time in the distilling process, as well as in the treatment
with decolourizing charcoal, and also in the purification by crystallization. I have
succeeded in directly obtaining from the crude glycerine by means of the improved
process which forms the subject of this invention, a light yellow, almost inodorous
product which as regards purity is equivalent to the so-called "refined" glycerine of
commerce.
The following will serve as an example of the said improved process.
100 parts of crude glycerine parts of zinc-vitriol which may or may not be
roasted are added and the mixture is heated; after the cooling of this mixture
about 2-7 parts of powder of caustic lime powder are added. These proportions can
of course be varied within certain limits according to the kind of crude glycerine
employed.
It is then only necessary to filter by means of a filter-press in order to obtain at
once a good commodity.
The effect of the reagents, besides that resulting from the property of every
precipitate carrying with it certain impurities and colouring matters, and the like,
consists in that the fatty acids of the crude glycerine, such as butyric acids and the
like form with zinc oxide, lime, and the like slightly soluble compounds, and are thus
removed.
In this improved process sulphate of zinc, dissolved in glycerine, forms with lime,
baryta, or the like, zinc 'hydrate and calcium, barium or like sulphate. The fatty
acids, such as butyric acids and the like are taken up by the zinc-oxide and form
insoluble salts; the calcium, barium or like sulphate is likewise almost insoluble in
glycerine. A small excess of lime, baryta, or the like is removed by the blowing
in of carbonic acid under heat, any traces of metal are precipitated by sulphide of
hydrogen, and an excess of sulphide of hydrogen is removed by the blowing through
of air.
The precipitate retained in the filter-press is regenerated by means of sulphuric
acid to form sulphate of zinc, and as such it can be used again for the purification;
the fatty acids are at the same time obtained as a by-product.
It will be understood that, as a matter of course, in lieu of sulphate of zinc other
metallic sulphates, such as sulphate of magnesia, sulphate of alumina, alum, sulphate
of iron, sulphate of copper, or the like; in lieu of lime either carbonate of lime or
baryta; and in lieu of sulphuric acid oxalic acid can be used.
Having now particularly described and ascertained the nature of my said
invention, and in what manner the same is to be performed, I declare that what
I claim is :-
First. The process of purifying crude glycerine by mixing the latter with
metallic sulphate or metallic oxalate, and subsequently treating the same with
hydrated oxide or carbonate of an alkaline earth.
Second. The recovery of the metallic salt used in this process, simultaneously
obtaining the fatty acids by treating the precipitate with sulphuric acid or oxali
acid.
ted this 13th day of July 1009.
HASELTINE, LAKE & Co.,
45, Southampton Buildings, London, Agents for the Applicant..