Year: 1887

page_text: Date of Application, 7th Nov., 1887
Specification Accepted, 13th Dec., 1887
I OSCAR KNUBLAUCH, Doctor of Philosophy, of Ehrenfeld, Köln 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 :-
It is known that in many gas mixtures employed or obtained in manufactures,
cyanogen or compounds thereof is present, but generally the amount of such cyanogen
or compounds is too small to render it capable of being extracted or recovered with
profit by heretofore known processes.
In such cases where it is essential to remove the cyanogen or compounds as for
instance in the manufacture of illuminating gas from coal, the gas mixtures bave been
passed over mixtures of oxydes of iron and alcalies or alcaline earths or substances
allied thereto such substances being always however in solid form.
Since the gas mixtures proposed to be treated according to this invention contain
large quantities of carbonic acid gas and of sulphide of hydrogen, on passing the gas
mixtures over the said substances in solid state, the carbonic acid combines with the
alcali (lime) to form carbonate of the alcali (chalk) and the iron combines with the
sulphur of the sulphide of hydrogen to form sulphide of iron, and only in such positions
where the iron, alcali and cyanogen meet together in correct proportions that is to say
only at the contact of the pieces of alcaline and iron compounds can Ferrocyanogen be
CD 627

page_text: Since the amount of the cyanogen in the gas mixture is generally very small, a very
small proportion of iron is required in the liquid, the amount being dependent on the
amount of cyanogen present.
If the proportions of iron to alcali or to alcaline earths or carbonate salts is varied,
the products will differ accordingly.
The process is as follows-The gases containing the cyanogen or prussic acid are
brought into intimate contact with the liquid containing in a dissolved or suspended state
one or more of the following; alcalis or alcaline earths in the form of oxydes hydrates
carbonates or sulphides, together with iron, manganese zinc or other metal or metals
of these groups in the form of oxydes hydrates or carbonates. These being either
brought into the liquid or formed therein by chemical decomposition or synthesis. The
intimate contact of the gases and liquid may be performed in apparatus of any suitable
construction as for instance a gas washer in compartments, scrubber of the like.
The proportions of ingredients in the liquid depends upon the materials employed
and differs according to the atomic relations of the elements and the molecular consti-
tution of the compounds; but they should be such that for one molecule of prussic
acid or of cyanogen, less than one molecule of iron is employed. The proportions of
iron employed in this process to those employed in the solid process is therefore
exceedingly small.—The liquid should be used in sufficient quantity to give sufficient
washing to the gas, but the quantity of liquid does not materially alter the reaction
and therefore does not constitute any part of this invention.
While, in the solid process, the small quantities of cyanogen compounds must be
dissolved off, in the improved process, when the liquid becomes sufficiently rich, it
may be removed for further treatment. An excess of iron over alcali causes the
cyanogen compounds to be precipitated.
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
1. The process for obtaining cyanogen or compounds thereof from gases or gas

page_text: mixtures containing the same, consisting in passing said gases through or in intimate
contact with a liquid containing one or more of the following substances-Oxydes
Hydrates Carbonates or Sulphides of the Alcalies or Alcaline Earths-and also one or
more of the following substances-Oxydes Hydrates or Carbonates of Irons manganese
or zinc.
2. The process for obtaining cyanogen or compounds thereof from gases or gas
mixtures containing the same together with a sufficiency of ammonia or other alcali,
consisting in passing said gases in intimate contact with liquid containing Oxyde
Hydrate or Carbonate of iron manganese or zinc.
DL: r
1007
CALL 1007
h day
Dated 1:
www
OSCAR KNUBLAUCH.
By Herbert & Co.,
18, Buckingham Street, Strand,
London, W.C.,
Agents to Applicant.