Improvements in Methods of Separating the Cyanogen Com- pounds from Gas Liquor or other Solutions containing Cyanogen Compounds.
Year: 1896

page_text: Date of Application, 6th Jan., 1896
Complete Specification Left, 29th Sept., 1896-4ccepted, 12th Dec.. 1896
PROVISIONAL SPECIFICATION.
Improvements in Methods of Separating the Cyanogen Com-
pounds from Gas Liquor or other Solutions containing
Cyanogen Compounds.
I, HENRY BOWER, of 29th Street, and Gray's Ferry Road, Philadelphia, U.S.A.,
do hereby declare the nature of this invention to be as follows:-
My invention relates to improvements in methods of separating from gas or
ammoniacal liquor the cyanogen compounds which it contains, and in economically
obtaining the sulphocyanide and ferrocyanide in separate form available for the
manufacture of the various commercial salts.
I add to the ammoniacal liquor, while cold and before it has been heated or
subjected to the action of an acid, metallic iron or a salt of iron, or both, in quantity
sufficient to convert the hydrocyanic acid, present in any form, into ferrocyanide
of iron, and the sulphocyanic acid, present in any form, into sulphocyanide of iron.
I then run the mixture into a still or treating vessel provided with means for
agitating its contents, add excess of lime to evolve ammonia, and distil the latter
off by means of heat and agitation in any of the well-known methods for recovering
ammonia.
So far, my process is similar to that described in Patent No. 2918 in the year
1882 granted to my correspondent Mr. Sydney Pitt.
Having driven off the ammonia, I add to the liquor, which holds in solution
ferrocyanide of calcium and sulphocyanide of calcium, an acidified solution of a salt
of copper (preferably cuprous chloride) sufficient to decompose the calcium ferro-
and sulphocyanides, a chloride being chosen on account of forming a soluble salt
of calcium, and a cuprous salt heing preferred to a cupric salt because the cuprous
sulphocyanide is insoluble. I thus obtain a precipitate containing ferrocyanide of
copper and sulphocyanide of copper mechanically mixed. After separating the
precipitate by settling, filtration, or other well-known means, I treat it while wet,
and preferably by agitation, with a sufficient quantity of finely divided metallic iron,
as iron filings or borings or "reduced iron," to decompose the copper salts, converting
the ferrocyanide of copper and the sulphocyanide of copper, respectively, into ferro-
cyanide of iron, which is insoluble, and sulphocyanide of iron, which is in solution,
and copper, which is in the metallic state.
The ferrocyanide of iron, on being treated with an alkali, an alkaline salt, or an
alkaline earth, gives as a result the ferrocyanides of the respective salt used, while
the solution of sulphocyanide of iron, on being evaporated, yields crystals of sulpho-
cyanide of iron; or this salt may he produced in an impure state by evaporating
to dryness out of contact with the air.
The treatment of the sulphocyanide with iron filings, as mentioned above, when
conducted under heat and pressure in a closed vessel, or autoclave, causes the
resultant metallic copper to combine with the sulphur of the sulphocyanide, producing
sulphide of copper and ferrocyanide of iron.
While I have described my process for the treatment of sulphocyanides produced
from gas or ammoniacal liquor, I do not desire to confine myself to a treatment
of sulphocyanides produced in this way alone, for sulphocyanides produced in any
other manner may be equally well treated by my process to produce sulphide of
copper and ferrocyanide of iron.
Dated this 27th day of December 1805

page_text: Improvements in Methods of Separating the Cyanogen Com-
pounds from Gas Liquor or other Solutions containing
Cyanogen Compounds.
I, GEORGE ROSENGARTEN BOWER, Administrator of Henry Bower deceased, of
29th Street, and Gray's Ferry Road, Philadelphia, U.S.A., 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:-
My invention relates to improvements in methods of separating from gas or
ammoniacal liquor the cyanogen compounds which it contains.
I proceed in the first place in the manner described in the Specification of my
previous Patent No. 8330 in the year 1895; that is to say :-I add to the
ammoniacal liquor while cold, and before it has been heated or subjected to the
action of an acid, metallic iron or salt of iron, or both, in quantity sufficient to
convert the hydrocyanic acid, present in any form, into ferrocyanide of iron, and
the sulphocyanic acid, present in any form, into sulphocyanide of iron. I then run
the mixture into a still or treating vessel provided with means for agitating its
contents, add excess of lime to evolve ammonia, and distil the latter off by means
of heat and agitation in any of the well-known methods for recovering ammonia.
Having driven off the ammonia, I add to the liquor, which holds in solution
ferrocyanide of calcium and sulphocyanide of calcium, an acidified solution of a salt
of copper (preferably cuprous chloride) sufficient to decompose the calcium ferro-
and sulphocyanides, a chloride being chosen on account of forming a soluble salt
of calcium and a cuprous salt being preferred to a cupric salt because the cuprous
sulphocyanide is insoluble. I thus obtain a precipitate containing ferrocyanide of
copper and sulphocyanide of copper mechanically mixed. After separating the
precipitate by settling, filtration, or other well-known means, I treat it while wet,
and preferably hy agitation, with a sufficient quantity of finely divided metallic
iron, as iron filings or borings or "reduced iron," to decompose the copper salts,
converting the ferrocyanide of copper and the sulphocyanide of copper, respectively,
into ferrocyanide of iron, which is insoluble, and sulphocyanide of iron, which is in
solution, and copper, which is in the inetallic state.
According to my present invention the treatment of the sulphocyanide with iron
filings, as mentioned above is conducted under heat and pressure in a closed vessel, or
autoclave, (a pressure of 70 lbs. per square inch and a corresponding temperature is
suitable) which causes the resultant metallic copper to combine with the sulphur of
the sulphocyanide of iron producing sulphide of copper and ferrocyanide of iron.
The ferrocyanide of iron, on being treated with an alkali. an alkaline salt, or an
alkaline earth, gives as a result the ferrocyanides of the respective salt used..
Similarly may treat a solution of sulphocyanide of iron obtained from any
source with metallic copper.
While I have described my process for the treatment of sulphocyanides produced
from gas or ammoniacal liquor, I do not desire to confine myself to a treatment
of sulphocyanides produced in this way alone, for sulphocyanides produced in any
other manner may be equally well treated by my process to produce sulphide of
copper and ferrocyanide of iron.
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. The process of recovering cyanogen compounds, from gas liquor or other
liquors containing ferrocyanides and sulphocyanides which process consists in adding

page_text: to the liquor a soluble copper salt to form insoluble ferrocyanide and sulphocyanide
of copper and then adding metallic iron to decompose the precipitate in an autoclave,
at an elevated temperature and under pressure substantially as described and for the
purposes set forth."
2. The process of producing ferrocyanide of iron and sulphide of copper from a
solution of sulphocyanide of iron by treating the solution with metallic copper in an
autoclave at an elevated temperature and under pressure substantially as described.
3. The process of producing ferrocyanide of iron and sulphide of copper, by
treating sulphocyanide of copper with metallic iron in an autoclave at an elevated
temperature and under pressure substantially as described.
Dated this 4th day of September 1896.
GEORGE R. BOWER,
Administrator of Henry Bower, Deceased.