Chemical Reactivity cont'd - hdbk1113cn10122

DOE-HDBK-1113-98

Radiological Safety Training for Uranium Facilities

Module 101 - Properties of Uranium

Uranyl compounds, such as uranyl nitrate, or UO 2(NO3)2, are chemical forms of uranium that are

often found in solution with water. They are generally yellow in color and are used in criticality

experiments.

Uranium reacts readily with air and water. For example, when uranium is machined, small chips

catch fire from the heat of the machining process. Shavings placed in water react to produce

hydrogen gas. The surfaces quickly oxidize to a hard black coating that is at first protective;

however, under adverse conditions, it corrodes and flakes.

Uranium also reacts with hydrogen or tritium gas to form urani um hydride (UH3). Uranium

"beds" a re commonl y used to s tore tr itium.

Uranium hexafluoride (UF6) reacts in moist air to produce hydrogen fluoride (HF) gas, which is

corrosive and can damage the lungs if breathed. Inhalation of HF has resulted in fatalities

following UF6 releases.

The chemical form of uranium is dependent on its intended use and its stage of production. For

example, UF6 is used during the enrichment process, and UO 2 is used as nuclear fuel. When

handling uranium compounds, the possibility of chemical reactions must not be overlooked.