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Published on: August 17, 2016
The electrochemical generation of small amounts of hydrogen cyanide
1UNESCO Laboratory of Environmental Electrochemistry, J. Heyrovský Institute of Physical Chemistry and Electrochemistry, Czechoslovak Academy of Sciences, Jilská 16, 110 00 Prague 1, Czechoslovakia.
Abstract:
Hydrogen cyanide was generated by constant-current oxidation of an aqueous solution of potassium thiocyanate at a platinum wire anode. In a solution of 0.1M potassium thiocyanate and 0.01M potassium sulphate at a nitrogen flow-rate of 3.5-5.0 ml sec , the rate of production of HCN was a linear function of the generation current I from 10 to 200 microA. The relative standard deviation for an HCN production rate of 6.07 ng sec (I = 130 microA) was 1.8% and that for 0.92 ng sec (I = 20 microA) was 5.9%. The time required to establish steady-state production after a change in the generation current was 10 min.
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