Formation of H2 and O2 in Radiolysis of Water Sorbed on PuO2

Samples of PuO₂ containing sorbed water, when stored at room temperature, release hydrogen and oxygen into the gas phase. At a given content of water, the rates of formation of H₂ and O₂ are in direct proportion to the dose rate of plutonium radiation. With increasing concentration of water from 0.3 to 3% the rates of formation of H₂ and O₂ increase by a factor of 60-100, which is caused by increase in both the energy of -radiation absorbed by water and radiation-chemical yields of formation of H₂ and O₂. The radiation-chemical yields of formation of oxygen and hydrogen at the 0.3% content of sorbed water are lower, and at the water content exceeding 1%, higher than the yields of these products in radiolysis of free water. On storage of powder-like and pelletized samples of PuO₂ of power reactor origin with a 3% water content for 150-200 days, the stationary concentration of hydrogen approximately corresponding to the initial concentration of sorbed water is established.