OR IMPROVED PROCESSES FOR PURIFYING GLYCERINE
Year: 1883

page_text: LETTERS PATENT to Herbert John Haddan, of Kensington; Middlesex for an
Invention of NEW OR IMPROVED PROCESSES FOR PURIFYING GLYCERINE
a communication to him from abroad by Carl Moldenhauer and Doctor Christian
TT
"
PROVISIONAL SPECIFICATION left by the said Herbert John Haddan at
the Office of the Commissioners of Patents on the 8th May 1883.
HERBERT JOHN HADDAN, of Kensington, Middlesex, "NEW OR IMPROVED
PROCESSES FOR PURIFYING GLYCERINE," a communication to me from abroad by
Carl Moldenhauer and Doctor Christian Heinzerling, persons resident at Frankfort
on the Main, in the German Empire,
Most of the methods hitherto proposed and applied for obtaining glycerine from
soap-maker's lye have the drawback that the glycerine thus won retains a large
percentage of common salt (from 5 to 8 per cent)
Glycerine in this state is useless for most purposes, and it is difficult to purify
the same by the methods hitherto known.
The following process has for its object to completely purify glycerine from
common salt, soda and volatile organic acids, while the substances thus eliminated
are at the same time recovered as by-products.
The raw saliferous glycerine won by any well known method, or the residual
lye produced by the manufacture of soap lye, are condensed by any known process
at a low temperature and completely separated from water.
"
The substance thus obtained and which I prefer to call raw material" is then
subjected to the following treatment.
The raw material is mixed with once to twice its volume of pure alcohol (Methyl
or ethyl-alcohol) and if this mash or mixture should not be alcaline, from 1 to 10
per cent of calcined carbonate of soda is added, hereupon the salts precipitated by
this operation are separated from the liquid by filtration or by any other known
process.
The alcoholic solution of glycerine, thus obtained, is mixed with sulphuric acid
or another acid having the same effect until an acid reaction takes place. If
sulphuric acid is used for this operation, the sodium combined with the organic

page_text: acids is precipitated, in the form of sulphate of Soda, which is then separated from
the alcoholic solution.
The alcoholic solution is now mixed with lead oxyde or soluble lead salts, or
other metallic salts, which form insoluble combinations with chlorine, in sufficient
quantities to precipitate the latter.
Glycerine purified in this manner is sufficiently pure to be applicable for many
technical purposes, as soon as the alcohol and the volatile ethers, formed during the
operation, have been distilled off.
For obtaining perfectly pure glycerine, the product obtained as described is
subjected to a distillation.
In many cases the treatment with oxyde of lead or other metallic salts may be
dispensed with; in these cases, however, after the alcohol has been distilled off, the
remaining glycerine, which still contains some chlorine, is distilled as many times
as may be necessary to remove the chlorine.
The alcohol is distilled off in a suitable still.
At the end of the operation, vapours of ether pass over, which have been
produced from the volatile organic acids such as propionic and butyric acid
contained in the soap lye, in the presence of alcohol and an acid.
The treatment with alcohol therefore serves to easily remove not only the
greatest part of the common salt but also, in the shape of volatile mixed ethers,
the volatile fatty acids contained in the crude glycerine, which acids are very
prejudicial, especially in the use of glycerine for the manufacture of nitro-
glycerine.
The ethers may be recovered in a pure state by fractional distillation
The metallic combinations of chlorine, for instance chloride of lead, resulting
from the separation of the chlorine, may, by suitable treatment, again be. trans-
formed into soluble metallic salts, which may again be applied for the separation of
chlorine.

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent filed
by the said Herbert John Haddan in the Great Seal Patent Office on the
5th November 1883.
HERBERT JOHN HADDAN, of Kensington, Middlesex, "NEW OR IMPROVED
PROCESSES FOR PURIFYING GLYCERINE," a communication to me from abroad by
Carl Moldenhauer and Doctor Christian Heinzerling, persons resident at Frankfort
on the Main, in the German Empire,
Most of the methods hitherto proposed and applied for obtaining glycerine from
soap-makers-lye have the drawback that the glycerine thus won retains a large
percentage of common salt (from 5. to 8 per cent).
Glycerine in this state is useless for most purposes, and it is difficult to purify
the same by the methods hitherto known.
The following process has for its object to completely purify glycerine from
common salt, soda and volatile organic acids, while the substances thus eliminated
are at the same time recovered as bye-products.
The raw saliferous glycerine won by any well known method, or the residual
lye produced by the manufacture of soap, are condensed by any known process at a
low temperature and completely separated from water. The substance thus
obtained and which I prefer to call "raw material" is then subjected to the
following treatment.
The raw material is mixed with once to twice its volume of pure alcohol (Methyl
or ethyl alcohol) and if this mash or mixture should not be alcaline, from 1 to 10
percent of calcined carbonate of soda is added; hereupon the salts precipitated by
this operation are separated from the liquid by filtration or by any other known
process. Instead of carbonate of soda, other suitable alkaline salt may be used.
The alcoholic solution of glycerine thus obtained, is mixed with sulphuric acid or.
another acid having the same effect until an acid reaction takes place. If sulphuric
acid is used for this operation, the sodium combined with the organic acids is
precipitated, in the form of sulphate of Soda, which is then separated from the
alcoholic solution.
:
The alcoholic solution is now mixed with lead oxyde or soluble lead salts, or
other metallic salts, which form insoluble combinations with chlorine, in sufficient
quantities to precipitate the latter.
Glycerine purified in this manner is sufficiently pure to be applicable for many
technical purposes, as soon as the alcohol and the volatile ethers, formed during
the operation, have been distilled off.
-
For obtaining perfectly pure glycerine, the product obtained as described is
subjected to a distillation. In many cases the treatment with oxyde of lead or
other metallic salts may be dispensed with; in these cases, however after the
alcohol has been distilled off, the remaining glycerine, which still contains some
chlorine, is distilled as many times as may be necessary to remove the chlorine.
The alcohol is distilled off in a suitable still.
At the end of the operation, vapours of ether pass over, which have been
produced from the volatile organic acids, such as propionic and butyric acid
contained in the lye, in the presence of alcohol and acid.
The treatment with alcohol therefore serves to easily remove not only the
greatest part of the common salt, but also, in the shape of volatile mixed ethers,
the volatile fatty acids contained in the crude glycerine, which acids are very
prejudicial, especially in the use of glycerine for the manufacture of nitro-
glycerine.
The ethers may be recovered in a pure state by fractional distillation.

page_text: The metallic combinations of chlorine, for instance chloride of lead, resulting
from the separation of the chlorine, may, by suitable treatment, again be trans-
formed into soluble metallic salts, which may again be applied for the separation of
chlorine.
Having now described the invention and in what manner the same is to be
performed, I wish it to be understood that I claim:
1. The treatment of residual lye produced by the manufacture of soap, or raw
saliferous glycerine, obtained by any other process, after having been relieved of
water, with alcohol in the presence of carbonate of soda or any other suitable
alkaline salt, substantially as described.
2. The treatment of glycerine containing organic acids in chemical combination,
with alcohol and sulphuric acid or other suitable acid for the purpose of converting
the organic acids into volatile ethers, and the separation and recovery of these
ethers by distillation as described.
3. The treatment of the alcoholic solution of glycerine with lead oxide or soluble
lead salts, or other metallic salts which form insoluble combinations with
chlorine.
In witness whereof I, the said Herbert John Haddan have hereunto set my
hand and seal this 5th day of November AD. 1883.