Improvements in the Manufacture of Cyanides.
Year: 1894

page_text: Date of Application, 21st Aug., 1894
Complete Specification Left, 20th June, 1895-Accepted. 21st Sept., 1895
Improvements in the Manufacture of Cyanides.
1, JOHN EDLINGTON CHASTER, of 30, Epple Road, Fulham, in the County
of Middlesex, Chemist, do hereby declare the nature of this invention to be as
follows:-
This invention relates to the manufacture on a commercial scale of cyanide of
potassium or other cyanide.
Cyanide is at present usually made from ferrocyanide of potassium, which is
dried and mixed through a sieve with dried carbonate of soda or of potash and
dried charcoal; the mixture being fused in a pot, with the result that cyanide of
potassium, cyanide of sodium and cyanates of the alkalies (the last in the proportion
of from 20 to 25 per cent.) are yielded. These products are sold on the basis of the
amount of cyanide of potassium and its equivalent which they contain.
The primary object of the present invention is to prevent or to largely reduce
the formation of cyanates.
In carrying out my invention, I mix anhydrous potassium ferrocyanide
(commonly called yellow prussiate of potash), anhydrous sodium ferrocyanide or
other anhydrous ferrocyanide of an alkali or alkaline earth with a suitable quantity
of dry alkaline carbonate or a carbonate of an alkaline earth. These substances,
in order that they may be thoroughly mixed, should be ground together. During
the grinding process, a suitable quantity of dry charcoal is added, together with
such a quantity of gas-tar, pitch, bitumen, asphaltum or other similar substance as
will bring the mixture to a pasty or mortar-like consistency. If the tar or other
substance be too thick, such a liquid as paraffin oil or naptha may be added. After
the mass has been thoroughly incorporated, it is treated in a furnace in the
ordinary way. Before being placed in the furnace, it may if preferred be subjected
to pressure.
By the above treatment, a much higher yield of cyanide than usual is obtained,
owing to the fusion taking place in a reducing or non-oxidising atmosphere, and
consequently the formation of cyanates is greatly diminished.
Dated the 18th day of August. 1894.
COMPLETE SPECIFICATION.
Improvements in the Manufacture of Cyanides.
I, JOHN EDLINGTON CHASTER, of 30, Epple Road, Fulham, in the County
of Middlesex, 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 :-
This invention relates to the manufacture on a commercial scale of cyanide of
potassium or other cyanide.

page_text: Cyanide is at present usually made from ferrocyanide of potassium, which is
dried and mixed through a sieve with dried carbonate of soda or of potash and
dried charcoal; the mixture being fused in a pot, with the result that cyanide of
potassium, cyanide of sodium and cyanates of the alkalies are yielded. These
products are sold on the basis of the amount of cyanide of potassium and its
equivalent which they contain.
The primary object of the present invention is to prevent or to largely reduce
the formation of what I believe to be cyanates, and correspondingly to increase the
formation of cyanides.
In carrying out my invention, I mix anhydrous potassium ferrocyanide
(commonly called yellow prussiate of potash), anhydrous sodium ferrocyanide or
other anhydrous ferrocyanide of an alkali or alkaline earth with a suitable quantity
of dry alkaline carbonate or a carbonate of an alkaline earth. From 65 to
72 per cent. of the former and about 20 per cent. of the latter would be appropriate.
These substances, in order that they may be thoroughly mixed, should be ground
together. During the grinding process, about 5 per cent. of dry charcoal is added,
together with such a quantity of gas-tar, pitch, bitumen, asphaltum or other
similar substance as will bring the mixture to a pasty or mortar-like consistency.
If the tar or other substance be too thick, such a liquid as paraffin oil or naphtha
may be added. After the mass has been thoroughly incorporated, it is treated
in a furnace in the ordinary way. Before being placed in the furnace, it may
preferred be subjected to pressure.
if
By the above treatment, a much higher yield of cyanide than usual is obtained,
owing as I believe to the fusion taking place in a reducing or non-oxidising
atmosphere.
Having now particularly described and ascertained the nature of this invention
and in what manner the same is to be performed, I claim :-
1. The herein described process for the manufacture of cyanides, consisting in
grinding together or otherwise thoroughly mixing (a) anhydrous potassium or
sodium ferrocyanide or other anhydrous ferrocyanide of an alkali or alkaline earth,
(b) dry alkaline carbonate or a carbonate of an alkaline earth, (c) dry charcoal
and (d) gas-tar, pitch, bitumen, asphaltum or similar substance, and then furnacing.
the pasty mass in the ordinary way.
2. In the manufacture of cyanides in the manner referred to in the preceding
claiming clause, the employment of gas-tar, pitch, bitumen, asphaltum or the like,
substantially as and for the purposes set forth.
Dated this 17th dow of June 1905