Plutonium production and

Attainment of the goal of balanced plutonium production and consumption and minimum inventory will require a number of decades. Paradoxically, achievement of the goal will be most important in the event that nuclear power is phased out, leaving large and increasingly accessible plutonium inventories in many countries if no provision for their destruction has been made. While the global abandonment of nuclear power is extremely... 

While the goal of bringing plutonium production and consumption into balance is a long term one, research and development on proliferation-resistant fuel cycles should be taking place at present. International cooperation ofthe appropriate countries in this R D is also essential. Failure to pursue a suitable R D effort and international cooperation is virtually certain to result in the adoption ofthe most proliferation-prone fuel cycle when the plutonium breeder is deployed in the next century. 

Hanford and Richland, Washington, was selected for industrial-scale plutonium production and chemical separations facilities on January 16, 1943. This site was named the Hanford Engineer Works (later named the Hanford Site). 

Gephart, R.E., A Short History of Plutonium Production and Nuclear Waste Generation, Storage, and Release at the Hanford Site, PNNL-SA-32153, Pacific Northwest National Laboratory, Richland, WA, 1999. 

Burdened by Manhattan Project security, with Du Pont taking over plutonium production and the Army moving hundreds of thousands of cubic yards of earth in imprecedented construction, Leo Szilard was advancing singlehandedly to attempt to extricate the process of decision from governmental restraints and to return it to the hands of the atomic scientists. 

However, for the sake of completeness, it has to be said that the Chernobyl-type reactors were not well known in the Western world. The pertinent information was kept somewhat confidential because this reactor could potentially be used for plutonium production and therefore it was interesting from a military point of view. ... 

Most studies and reviews of nuclear weapons and their effects have focused almost exclusively on what would happen if they were used. Notably, though, this represents only one phase in the life cycle of nuclear weapons, which includes uranium mining, milling, conversion, and enrichment plutonium production and separation nuclear fuel transport other raw material production and weapon assembly, transport, storage, testing, maintenance and refurbishment, use, and disassembly and disposal, including recycling or disposal of aU component parts [7]. 

Initially, the only means of obtaining elements higher than uranium was by a-particle bombardment of uranium in the cyclotron, and it was by this means that the first, exceedingly minute amounts of neptunium and plutonium were obtained. The separation of these elements from other products and from uranium was difficult methods were devised involving co-precipitation of the minute amounts of their salts on a larger amount of a precipitate with a similar crystal structure (the carrier ). The properties were studied, using quantities of the order of 10 g in volumes of... 

Argon-40 [7440-37-1] is created by the decay of potassium-40. The various isotopes of radon, all having short half-Hves, are formed by the radioactive decay of radium, actinium, and thorium. Krypton and xenon are products of uranium and plutonium fission, and appreciable quantities of both are evolved during the reprocessing of spent fuel elements from nuclear reactors (qv) (see Radioactive tracers). 

Uranium. The uranium product from the PUREX process is in the form of uranyl nitrate which must be converted to some other chemical depending on anticipated use. One route to MO fuel is to mix uranium and plutonium nitrates and perform a coprecipitation step. The precipitate is... 

The Hanford N Reactor. The Hanford N reactor was built in 1964 for purposes of plutonium production during the Cold War. It used graphite as moderator, pierced by over 1000 Zircaloy 2 tubes. These pressure tubes contained slightly enriched uranium fuel cooled by high temperature light water. The reactor also provided 800 MWe to the Washington PubHc Power Supply System. This reactor was shut down in 1992 because of age and concern for safety. The similarity to the Chemobyl-type reactors played a role in the decision. 

The Natural Reactor. Some two biUion years ago, uranium had a much higher (ca 3%) fraction of U than that of modem times (0.7%). There is a difference in half-hves of the two principal uranium isotopes, U having a half-life of 7.08 x 10 yr and U 4.43 x 10 yr. A natural reactor existed, long before the dinosaurs were extinct and before humans appeared on the earth, in the African state of Gabon, near Oklo. Conditions were favorable for a neutron chain reaction involving only uranium and water. Evidence that this process continued intermittently over thousands of years is provided by concentration measurements of fission products and plutonium isotopes. Usehil information about retention or migration of radioactive wastes can be gleaned from studies of this natural reactor and its products (12). 

In plutonium-fueled breeder power reactors, more plutonium is produced than is consumed (see Nuclearreactors, reactor types). Thus the utilisa tion of plutonium as a nuclear energy or weapon source is especially attractive to countries that do not have uranium-enrichment faciUties. The cost of a chemical reprocessing plant for plutonium production is much less than that of a uranium-235 enrichment plant (see Uranium and uranium compounds). Since the end of the Cold War, the potential surplus of Pu metal recovered from the dismantling of nuclear weapons has presented a large risk from a security standpoint. 

Cost and Value of Plutonium. The cost of building all U.S. nuclear weapons has been estimated as 378 biUion in 1995 dollars (24). If half of this sum is attributed to U.S. weapons-grade plutonium production (- lOOt), the cost is 1.9 x 10 /kg of weapons-grade Pu. Some nuclear weapons materials (Be, enriched U, Pu) also have value as a clandestine or terrorist commodity. The economic value of reactor-grade plutonium as a fuel for electric power-producing reactors has depended in the past on the economic value of pure 235u... 

Sepa.ra.tion of Plutonium. The principal problem in the purification of metallic plutonium is the separation of a small amount of plutonium (ca 200—900 ppm) from large amounts of uranium, which contain intensely radioactive fission products. The plutonium yield or recovery must be high and the plutonium relatively pure with respect to fission products and light elements, such as lithium, beryUium, or boron. The purity required depends on the intended use for the plutonium. The high yield requirement is imposed by the price or value of the metal and by industrial health considerations, which require extremely low effluent concentrations. 

The plutonium extracted by the Purex process usually has been in the form of a concentrated nitrate solution or symp, which must be converted to anhydrous PuF [13842-83-6] or PuF, which are charge materials for metal production. The nitrate solution is sufficientiy pure for the processing to be conducted in gloveboxes without P- or y-shielding (130). The Pu is first precipitated as plutonium(IV) peroxide [12412-68-9], plutonium(Ill) oxalate [56609-10-0], plutonium(IV) oxalate [13278-81-4], or plutonium(Ill) fluoride. These precipitates are converted to anhydrous PuF or PuF. The precipitation process used depends on numerous factors, eg, derived purity of product, safety considerations, ease of recovering wastes, and required process equipment. The peroxide precipitation yields the purest product and generally is the preferred route (131). The peroxide precipitate is converted to PuF by HF—O2 gas or to PuF by HF—H2 gas (31,132). 

Nuclear Waste Reprocessing. Liquid waste remaining from processing of spent reactor fuel for military plutonium production is typically acidic and contains substantial transuranic residues. The cleanup of such waste in 1996 is a higher priority than military plutonium processing. Cleanup requires removal of long-Hved actinides from nitric or hydrochloric acid solutions. The transuranium extraction (Tmex) process has been developed for... 

The Magnox reactor concept owes its origins to a design study conducted at Harwell, U.K., diuing the early 1950s. The reactor was designed with the dual role of plutonium and power production, and was known by the code word PIPPA... 

The DOE N-Reactor is one of the plutonium production reactors located on the Hanford Reservation near Richland, Washington. It is graphite moderated, pressurized water reactors that in addition to production of special nuclear materials also provided steam to turbine generators owned by the Washington Public Power Supply System for electric power production. It began op ition in 1 is put into standby status in 1988 and closed because of similarities to Chernobyl. 

Congress has decided that reprocessing will not be practiced in this country so that we will not be in the plutonium production business. This seems like a safe thing to do since this action will minimize terrorism threats. Reprocessing generates chemi cal wastes but greatly reduces the volume of the highly radioactive waste. It also isolates plutonium and unused fuel for possible use as new fuel. 

To review the available evidence, the plutonium in both compounds is trivalent, the compounds have coordinated or bonded ethylenic groups, and the empirical formulae are PuIjC H THF (the reaction product) and PuIgCgH (the pyrolytic product). Formulae that are consistant with this evidence are PuI3(CH2=CH2) 4THF for the reaction product, and PuI2(CH CH2) for the pyrolytic product. The evidence is only sufficient to propose these compositions, and until corroborative measurements can be made, these formulae should be considered tentative. 

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