Plutonium Chlorides - doe-std-1128-98

DOE-STD-1128-98

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 gastrointestinal (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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