Improvements in the Manufacture of Carbon Anodes for Electrolytical Processes.
Year: 1896

page_text: Date of Application, 18th June, 1896-Accepted, 18th July, 1896
COMPLETE SPECIFICATION.
Improvements in the Manufacture of Carbon Anodes for Electrolytical
Processes.
I, PETER JENSEN, of 77 Chancery Lane, London, Chartered Patent Agent, do
hereby declare the nature of this invention a communication to me from abroad by
Hans Cappelen and Diderik Cappelen both of Skien, Norway, Manufacturers and
in what manner the same is to be performed to be particularly described and
ascertained in and by the following statement :-
The carbon anodes usually applied in the electrolysis of salt solutions are not
very constant and are in a high degree liable to be consumed away or to smoulder
away especially if rather high power currents are used. In a greater or less
degree this is the case with all kinds of carbon but especially with the retort
carbon used in large installations and contingent upon its porosity and the
decomposing processes coupled with gas evolution taking place in the pores of the
carbon.
This defect in carbon anodes which causes the bath to become dirty and the
continuity of the working to be impaired is according to the present invention
overcome by impregnating the pieces of carbon (whether natural or artificial and
whether in the raw condition or shaped) with an electrically and chemically inert
material which by filling all the pores prevents the entry of the liquid and thus
also the noxious influence of the current upon the carbon. The inventors have
used advantageously as impregnating materials such fatty matters which when
heated become fluid, so that the impregnation can easily take place while they
after the pieces of carbon have been soaked therewith and then left to cool fill the
pores of the carbon in a set or solid condition. Paraffin is a material particularly
suitable for the purpose, but a whole series of more or less analogous materials may
of course be used.
By such an impregnation the carbon annodes are perfectly preserved without
losing any of their conductivity. The treatment may be carried out so that the
material penetrates the whole mass, or so that only the outer layers are penetrated.
By treating the anodes in this manner not only the direct consequences of their
smouldering away are avoided but certain other advantages are gained; it becomes
for instance possible to employ a considerably higher density of current and inferior
qualities of carbon are rendered quite applicable. The prevention of the decomposing
processes in the interior of the auodes also involves that noxious secondary processes
and consequent loss of power are avoided.
Having now particularly described and ascertained the nature of the said inven-
tion and in what manner the same is to be performed as communicated to me by
my foreign correspondents I declare that what I claim is
1. Anodes for electrolytical processes consisting of natural or artificial carbon
the pores of which are filled with an inert material as described.
2. The process for manufacturing annodes as firstly claimed consisting in dipping
the pieces of carbon whether in the raw condition or shaped in melted paraffin or
other suitable fatty material which sets by cooling as described.
Dated this 18th day of June 1896.
JENSEN & SON,
77 Chancery Lane, London, W.C., Patent Agents.