Isotopic Effects of Hydrogen During the Decomposition of Water in Electrolysis with a Solid Polymer Electrolyte

The partition coefficients of hydrogen isotopes in the decomposition of water in electrolyzers with a solid polymer electrolyte are measured in a wide range of deuterium content in the initial water (from the natural content up to close to 100%), including for water containing trace concentrations of tritium. Equations describing the temperature dependence of the partition coefficients (temperature range 298–333 K) and the deuterium content dependence of the tritium partition coefficient are obtained. Partition coefficients are presented for binary isotopic mixtures protium–deuterium, protium–tritium, deuterium–tritium. 1 figure, 3 tables, 17 references.