Electrochemical cell

Abstract

An electrochemical cell is described, which provides a reliable gas generation even under unfavorable environmental conditions and with significant changes in temperature and environment. Furthermore the cell has a long life time. The electrolyte of this electrochemical cell comprises at least one ionic liquid containing thiocyanate ions for the generation of hydrogen cyanide gas. Preferred substances for the composition of the electrolyte and for the provision of thiocyanate ions in the electrolyte are specified.

Description

FIELD OF THE INVENTION[0001]The present invention relates to an electrochemical cell for generating hydrogen cyanide gas using a generator electrode and a counter electrode.BACKGROUND OF THE INVENTION[0002]Electrochemical cells for generating test gases for gas analysis devices are known, e.g. from German patent specification 26 21 677, for various gases, but not for hydrogen cyanide gas.[0003]From document Z. Tocksteinová, F. Opekar, “The Electrochemical Generation of Small Amounts of Hydrogen Cyanide”, Talanta, 1986, vol. 33, no. 8, pages 688-690 a method for generating hydrogen cyanide gas using an electrochemical cell is known, wherein hydrogen cyanide gas is generated by oxidation of thiocyanate ions. The gas is generated via controlled oxidation of thiocyanate in aqueous solution according to reactionSCN−+4 H2O→6 e−+SO42−+HCN+7 H+[0004]A platinum electrode completely submerged in an aqueous electrolyte is flushed by nitrogen, so as to transport the generated hydrogen cyanide g...

AI Technical Summary

Benefits of technology

The invention provides an electrochemical cell that can generate hydrogen cyanide gas for a long time even under extreme environmental conditions. The use of ionic liquids as electrolyte allows for stable gas generation without failure, even at changing temperatures. A mixture of at least two ionic liquids can be used to easily adjust the melting point and water absorption capacity of the electrolyte. The addition of layers of glass fiber between the electrodes, impregnated with the ionic liquid, can improve the efficiency of the gas generation process.

Problems solved by technology

Besides the fact that the use of such a gas generator is only possible under laboratory conditions, this gas generator is unfavorable in particular due to the electrolyte which is an aqueous solution.

Thus in practical applications for example climatic influences will cause loss of electrolyte, which does not allow for a reliable generation of hydrogen cyanide gas in controllable and constant amounts or might even cause a complete functional failure of such a generator.