Conversion of tritiated hydrogen to water in the atmosphere. [Review of current information; 96 references]

Technical Report · Wed Sep 01 04:00:00 EDT 1976

DOI:https://doi.org/10.2172/7330458· OSTI ID:7330458

Burger, L L

The report summarizes present information on the atmospheric reactions of tritium. The global distribution of hydrogen and of water is first considered. Data on tritium distribution are then compared and, finally, known reactions which may convert tritiated hydrogen-containing molecules are discussed. Approximately 99 percent of the world's inventory of tritium exists as HTO. Although most of it is in the ocean, a significant portion still resides in the stratosphere. However, in the troposphere, which is the primary concern of this review, most of the tritium is in the form of HT, a smaller amount as HTO, and a much smaller but still significant amount as CH/sub 3/T. Further, the tritium-to-hydrogen ratio in the troposphere is higher in hydrogen and in methane than it is in water vapor. The formation of HTO by exchange of HT or T/sub 2/ with water or by direct oxidation with oxygen, in the absence of catalysts, is extremely slow at concentrations in the atmosphere that might exist a few minutes after a tritium release. Photochemical oxidation may be the predominant conversion mechanism and over larger periods of time may combine with bacterial action to serve as the principal pathways of conversion of HT (or T/sub 2/) and CH/sub 3/T to HTO or other more reactive forms of tritium. The net conversion rate following a tritium release to the atmosphere would be expected to be less than 1 percent in 24 hr. The significance of the relatively high tritium content in atmospheric methane needs evaluation. Monitoring of CH/sub 3/T has been largely neglected in the past. Considerable uncertainty exists in some of the data on which these conclusions are based and recommendations are made for further work.

• Research Organization: Battelle Pacific Northwest Labs., Richland, Wash. (USA)
• DOE Contract Number: E(45-1)-1830
• OSTI ID: 7330458
• Report Number(s): BNWL-2113
• Country of Publication: United States
• Language: English

Related Subjects

060500 -- Fusion Fuels-- Health & Safety-- (-1987)
38 RADIATION CHEMISTRY, RADIOCHEMISTRY, AND NUCLEAR CHEMISTRY
400702* -- Radiochemistry & Nuclear Chemistry-- Properties of Radioactive Materials
70 PLASMA PHYSICS AND FUSION TECHNOLOGY
BETA DECAY RADIOISOTOPES
BETA-MINUS DECAY RADIOISOTOPES
CHEMICAL REACTIONS
DOCUMENT TYPES
EARTH ATMOSPHERE
HYDROGEN ISOTOPES
ISOTOPES
LABELLED COMPOUNDS
LIGHT NUCLEI
NUCLEI
ODD-EVEN NUCLEI
OXIDATION
RADIOISOTOPES
REVIEWS
THERMONUCLEAR REACTOR MATERIALS
TRITIUM
TRITIUM COMPOUNDS
TRITIUM OXIDES
TROPOSPHERE
YEARS LIVING RADIOISOTOPES