Application of an electrochemical cell to hydrogen detection in cover gas and to carbon activity determination in sodium

The gas measuring unit of the device OXYLYT works on the basis of a solid electrolyte cell with coulometric titration of oxidisable compounds in an inert gas stream. The extended use of the cell for hydrogen measuring in the cover gas of the sodium-water steam generators of the reactor BOR 60 has justified its integration in the leak detection system. A laboratory type cell has also been used for the coulometric detection of carbon monoxide in the gas stream from the exit of a carbon sensor which employs a wuestite layer in the interior surface of an iron diffusion membrane. Measurements with this combination have been carried out so far in the sodium temperature range from 700 to 750 C and the carbon activity range from 0.01 to 0.2. (author)