Oxides - std301320000029

DOE-STD-3013-2000

creation of potentially pyrophoric hydrides [e.g., see USDOE 1994a, Haschke/Martz

1998]. Also, reaction of plutonium metal with water and air can lead to highly

reactive hydrides and nitrides under some circumstances [ANS 1980, Haschke/Martz

1998]. Since plutonium metal allowed by this Standard has low specific surface area

(see Criterion 6.1.1.1 for details) and is therefore easily examined, visual inspection

for free water and organic materials with the unaided eye is sufficient to assure that

unsafe quantities of hydrides and nitrides cannot form by this mechanism during

storage.

3. Since plutonium turnings pressed into briquettes cannot be examined to determine

that they meet the requirements of Criteria 6.1.2.1 and 6.1.2.2, they are not

acceptable storage package contents. They should be converted to stable oxide

powder.

A.6.1.2

Oxides

1. The stabilization requirements of this Standard are intended to accomplish the

following objectives:

eliminate reactive materials such as finely divided metal or sub-stoichiometric

plutonium oxides;

eliminate organic materials;

reduce the water content to less than 0.5 wt% and similarly reduce equivalent

quantities of species such as hydrates and hydroxides that might produce water;

minimize potential for water readsorption above the 0.5 wt% threshold; and

stabilize any other potential gas-producing constituents.

To achieve these objectives, this Standard specifies that oxide material will be

placed in a continuously oxidizing atmosphere at a material temperature of at least

950C for a minimum of two hours. The following discussion outlines the technical

basis that ensures that the calcination requirements of the Standard will accomplish

the above objectives.