Radiochemical reactions between tritium and humid air

Radiochemical reactions between pure tritium (T/sub 2/) and moist air have been examined using real-time Raman spectroscopy. The reacting constituents were contained in a 1 cm/sup 3/ quartz cell sealed by a quartz-to-metal seal leading to a valve. A near-stoichiometric mixture of T/sub 2/ and O/sub 2/ was introduced into the cell, and the time evolution of the composition was monitored at 297 K for twenty-nine days. The production of T/sub 2/O was observed in these experiments, for the first time unambiguously detected in Raman spectroscopy. T/sub 2/O exhibits a relatively weak vibrational band at /spl sim/2241 cm/sup -1/. The radiochemical production of tritiated water did not occur in the expected 2:1 ratio, but rather with the O/sub 2/ disappearing totally when the T/sub 2/ was only slightly over halfway depleted. After the disappearance of O/sub 2/, the T/sub 2/ partial pressure continued to decrease, but at a slower rate. The initial water in the moist-air mixture disappeared totally after about 15 hours, with no concomitant production of HT. A small quantity of CO/sub 2/ was also detected, presumably produced by radiochemically driven reactions with stainless steel components.