Improved Process for the Manufacture of Carbonate of Ammonia.
Year: 1893

page_text: Date of Application, 18th Apr., 1893
Complete Specification Left, 16th Jan., 1894-Accepted, 17th Feb., 1894
PROVISIONAL SPECIFICATION.
Improved Process for the Manufacture of Carbonate of Ammonia.
I, CARL RASPE of 21 Sophienstrasse, Berlin in the Empire of Germany,"do
hereby declare the nature of this invention to be as follows:-
Carbonate of ammonia is at present made by heating ammonia salts, preferably
sulphate of ammonia with lime, and catching the sublimated carbonate of ammonia
in cooling apparatus.
By using a sufficiently pure salt of ammonia free from empyreuma, a sufficiently
pure carbonate free from empyreuma is also obtained.
The manufacture of carbonate of ammonia therefore always presumed the
existence of ammonia salts for obtaining which the waste water from gas works,
coke ovens, blast furnaces, etceteca, was used as raw material. The manufacture of
sufficiently pure carbonate of ammonia must always therefore be preceded by the
production of pure ammonia salts from such impure water which is rich in
empyreuma.
This invention has therefore for its object to avoid this preliminary production
of ammoniacal salts, and thereby to simplify and cheapen the manufacture of
carbonate of ammonia without injuring the purity of the sa.ne.
The experiments made for attaining this object showed that it is possible to
obtain carbonate of ammonia in a sufficiently pure condition direct from such
waters as already contain carbonate of ammonia, as the empyreuma can then be
completely removed.
The purification by means of carbon was found to be insufficient, or the same
required a great quantity of carbon, as this latter rapidly became useless. It was
found then by these experiments that the cause of this might be the large amount
or the character of the empyreuma present, and that the purification by means of
carbon may lead to a good result with a proportionately small consumption of
carbon, if, before this purification by means of carbon, the water containing
carbonate of ammonia be treated or agitated with a fatty oil for the object of
removing a large part of the empyreuma, and afterwards the purification by means
of carbon takes place for removing the remainder of the empyreuma.
The use of fatty oil alone was found in the same way as is the case with carbon
to be not at all sufficient, as always a considerable quantity of empyreuma still
remained behind in the solution of carbonate of ammonia treated with fatty oil.
The above named combined use of fatty oil and carbon alone led to the desired
result.
If, according to this invention, one of such fractional removals of empyreuma be
employed, it is possible, as will be hereinafter shown as regards the main impurities,
to obtain from waters containing carbonate of ammonia and especially from the
liquid products of distillation of fossil bitumen or fuel, bones or the like, by a direct
process, a sufficiently pure carbonate of ammonia. Such waters contain mostly or
almost always sulphur which it is preferable to remove as metallic sulphide by the
addition of metallic salts (preferably metallic carbonate) metallic oxides or metallic
hydroxides. Such water may be treated with carbonate of zinc until the sulphur
is fully removed, corresponding quantities of carbonate of ammonia and insoluble
sulphide of zinc being formed. The carbonate of ammonia is then agitated with
fatty oil into which a considerable quantity of the empyreuma is transferred and
which may be easily separated from the water as it floats upon the same.
The
carbonate of ammonia water thus treated is then only submitted to a distillation

page_text: for which a dephlegmating apparatus is preferably employed, the connecting points
of which, which are easily stopped up by any carbonate of ammonia which may be
condensed, are preferably made as wide as possible, or arranged so as to allow of
their being heated.
The carbonate of ammonia vapours produced by this means are passed through
preferably freshly made wood charcoal in order to be freed from the remainder of
their empyreuma, and are then brought to condensation. The drying of the
carbonate of ammonia may also be assisted or performed by the use of drying
materials, either with dry carbonates, or with dry potash or soda. Any ammonia
escaping may be caught and condensed simultaneously with the carbonate of
ammonia and after the condensation of the same. The carbon filter is preferably
kept warm in order to prevent any premature condensation of the carbonate of
ammonia.
If the water which is to be treated contain other ammonical salts than carbonate
of ammonia, alkaline carbonate, preferably soda, may be added to the water before
the distillation.
In such a way, a considerable reduction in the cost of making carbonate of
ammonia is obtained, as the same is thus recoverable, as hereinbefore described, in
a state of perfect purity direct from the raw material avoiding all intermediate
products such as ammonia salts; the carbonate of ammonia obtained by this process
presenting a white, outwardly dry, pure salt.
Dated this 17th day of April 1893.
WM. P. THOMPSON & Co.,
Of 6, Lord Street, Liverpool, Agents for the Applicant.
I, CARL RASPE of 21 Sophienstrasse, Berlin, in the Empire of Germany,
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:-
Carbonate of ammonia is at present made by heating ammonia salts, preferably
sulphate of ammonia with lime, and catching the sublimated carbonate of ammonia
in cooling apparatus.
By using a sufficiently pure salt of ammonia free from empyreuma, a sufficiently
pure carbonate free from empyreuma is also obtained.
The manufacture of carbonate of ammonia therefore always presumed the
existence of ammonia salts, for obtaining which the waste water from gas works,
coke ovens, blast furnaces, etcetera, was used as raw material. The manufacture
of sufficiently pure carbonate of ammonia must always therefore be preceded
by the production of pure ammonia salts from such impure water which is rich in
empyreuma.
This invention has therefore for its object to avoid this preliminary production
of ammoniacal salts, and thereby to simplify and cheapen the manufacture of carbonate
of ammonia without injuring the purity of the same.
The experiments made for attaining this object showed that it is possible to
to obtain carbonate of ammonia in a sufficiently pure condition direct from such
waters as already contain carbonate of ammonia, as the empyreuma can then be
completely removed.
The purification by means of carbon was found to be insufficient, or the same
required a great quantity of carbon, as this latter rapidly became useless. It was
found then by these experiments that the cause of this might be the large amount
or the character of the empyreuma present, and that the purification by means of

page_text: carbon may lead to a good result with a proportionately small consumption of carbon,
if, before this purification by means of carbon, the water containing carbonate of
ammonia be treated or agitated with a fatty oil for the object of removing a large
part of the empyreuma, and afterwards the purification by means of carbon takes
place for removing the remainder of the empyreuma.
The use of fatty oil alone was found in the same way as is the case with
carbon to be not at all sufficient, as always a considerable quantity of empyreuma
still remained behind in the solution of carbonate of ammonia treated with fatty
oil. The above named combined use of fatty oil and carbon alone led to the
desired result.
If, according to this invention, one of such fractional removals of empyreuma be
employed, it is possible, as will be hereinafter shown as regards the main impurities,
to obtain from waters containing carbonate of ammonia and especially from the
liquid products of distillation of fossil bitumen or fuel, bones or the like, by a
direct process, a sufficiently pure carbonate of ammonia. Such waters contain
mostly or almost always sulphur, which it is preferable to remove as metallic
sulphide by the addition of metallic salts (preferably metallic carbonate) metallic
oxides or metallic hydroxides. Such water may be treated with carbonate of
zine until the sulphur is fully removed, corresponding quantities of carbonate of
ammonia and insoluble sulphide of zinc being formed. The carbonate of ammonia is
then agitated with fatty oil into which a considerable quantity of the empyreuma
is transferred and which may be easily separated from the water as it floats upon
the same.
The carbonate of aminonia water thus treated is then only submitted to
a distillation for which a dephlegmating apparatus is preferably employed, the
connecting points of which, which are easily stopped up by any carbonate of ammonia
which may be condensed, are preferably made as wide as possible, or arranged so.
as to allow of their being heated.
The carbonate of ammonia vapours produced by this means are passed through
preferably freshly made wood charcoal in order to be freed from the remainder of
their empyreuma, and are then brought to condensation. The drying of the
carbonate of ammonia may also be assisted or performed by the use of drying
materials, either with dry carbonates, or with dry potash or soda. Any ammonia
escaping may be caught and condensed simultaneously with the carbonate
of ammonia and after the condensation of the same. The carbon filter is prefer-
ably kept warm in order to prevent any premature condensation of the carbonate
of ammonia.
If the water which is to be treated contain other ammoniacal salts than carbonate
of ammonia, alkaline carbonate, preferably soda, may be added to the water before
the distillation.
In such a way, a considerable reduction in the cost of making carbonate of
ammonia is obtained, as the same is thus recoverable, as hereinbefore described, in
a state of perfect purity direct from the raw material, avoiding all intermediate
products, such as ammonia salts; the carbonate of ammonia obtained by this process
presenting a white, outwardly dry, pure salt.
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. An improved process for removing as completely as possible the empyreuma
from the carbonate of ammonia present in solutions which contain empyreuma, in
order to directly obtain as pure a carbonate of ammonia as possible, consisting in
first treating such solutions with a fatty oil, and then conducting through carbon
the carbonate of ammonia vapour produced from such previously purified solutions,.
by the distillation of the same.
2. The process described in Claim for the manufacture of carbonate of
ammonia in as dry a form as possible, consisting in condensing, by dephlegmation,
the purified vapour obtained in the manner described in Claim 1, which

page_text: dephlegmation may be assisted or replaced by employing dry carbonates as
drying materials.
3. The process described in Claims 1 and 2 for producing directly pure
carbonate of ammonia from the liquid products of the distillation of fossil bitumen
or fuel, or from bones, consisting in, first, freeing such liquids from any sulphur
present by means of any sulphur removing substances, such as metallic salts,
metallic carbonate, metallic oxide or metallic hydroxide, then treating the same
with fatty oil, and afterwards subjecting to distillation the liquids treated in the
manner hereinbefore described, such liquids being treated with alkaline carbonate for
converting any other ammonia salts, dephlegmation being employed which may be
assisted or replaced by the use of dry carbonates, whilst the carbonate of ammonia
vapours produced are passed through carbon in order to be freed from the remainder
of their empyreuma.
Dated this 15th day of January 1894.
WM. P. THOMPSON & Co.,
Of 6, Lord Street, Liverpool, Agents for the Applicant.