Plutonium Chlorides - STD-1128-98master0042

DOE-STD-1128-98

Guide of Good Practices for Occupational Radiological Protection in Plutonium Facilities

2.3.3.5 Plutonium Chlorides

Chloride salts, which are a very important category of residues, are byproducts of

pyrochemical operations. Pyrochemical chloride-based operations currently in

use include:

-- DOR

-- electrorefining (ER)

-- molten salt extraction (MSE)

-- pyroredox.

Treatment of chloride-based residues is especially challenging for aqueous

recovery techniques because of corrosion problems with stainless steel

equipment. At the LANL site, Kynar-lined gloveboxes were to be installed to

evaluate their behavior in production-scale operations. The Rocky Flats Plant

(RFP) has also had extensive experience in aqueous recovery of plutonium from

chloride-based residues (Muscatello et al., 1986a, 1986b, 1987). Cesium

chloroplutonate, Cs2PuCl6, was proposed as a primary analytical standard due to

its stability to alpha radiolysis and may now have application as a storage form.

It was first prepared by Anderson (1949). There is no evidence of water

absorption at relative humidities as high as 53% (Miner et al., 1963). After 64

days at 90% relative humidity, Cs2PuCl6 forms a paste.

2.3.3.6 Plutonium Fuels

Plutonium and plutonium-uranium fuel mixtures were developed and tested in

experimental reactors to prove the feasibility of operating power reactors. These

fuels included both liquids and solids consisting of alloys and ceramic mixtures.

Wick (1967) and Schneider and Roepenack (1986) provide comprehensive lists

of fuels. Because of their pyrophoric nature, some of these alloys and

compounds require special care and handling when exposed to reactive liquids or

gases.

2.4

RADIOLOGICAL EFFECTS ON HUMANS

The radiobiological properties of plutonium and other transuranic (TRU) elements are known

primarily from experiments performed on rats, dogs, baboons, and rabbits. Human data on

plutonium are limited. Reviews of the vast literature on plutonium include Hodge et al. (1973);

ICRP 19 (1972); ICRP 30, Part 1 (1979); ICRP 48 (1986); ICRP 30, Part 4 (1988b); and

Liverman et al. (1974). ICRP 30, Part 1 (1979) and ICRP 48 (1986) report different gastro-

intestinal (GI) absorption and biodistribution parameters. The committed effective dose

equivalents, calculated using the models of the two publications, will differ by about 10%, with

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