HYDROGEN RELEASE FROM Pd ELECTRODES AFTER ION CURRENT IMPACT DURING ELECTROLYSIS PROCESS

The out gassing rate of hydrogen from palladium cathode and anode after exposure to ion current during electrolysis process in the (H2O+1wt.% NaHCO3) electrolyte was measured in dependence on temperature and the duration of exposure. The activation energy of the hydrogen out gassing from the cathode was calculated to be E ≈ 46 kJ/mole (for the anode E ≈ 18 kJ/mole). The amount of hydrogen desorbed from the electrodes was estimated. For the Pd cathode, it was about 650 Normal (N) cm3 H2 (H/Pd ≈ 0.48). Hydrogen out gassing rate (hydrogen release) at the maximum temperature of 650 °С was 0.3 Ncm3 H2/s. For the Pd anode these values were much lower (0.21 Ncm3 and 0.05 Ncm3 H2/s, consequently). Mass spectra of the mixtures of gases, generated during electrolysis mode, and the one, desorbed from electrodes under heating in a vacuum, were measured. Current-voltage characteristic of the electrolysis process is presented, too. It has been shown, that at electrolytes temperature of ≈ 50 °C and the pressure in the electrolyze chamber of 1 atm, the generated gas is hydrogen of 92 vol.%. Hydrogen desorbed in a vacuum from Pd-cathode after electrolysis process is high pure hydrogen (better than 99.99 vol.%). Physical-chemical reasons are analyze to explain hydrogen sorption and out gassing behavior in Pd electrodes during and after electrolysis.