Butex process solvent used

Following successful pilot-plant tests at Chalk River [N4], the Butex process was adopted for large-scale separation of plutonium, uranium, and fission products from natural uranium irradiated to low bumup at the Windscale plant of the U.K. Atomic Energy Authority [H8]. Even after its use in this application was replaced by the Purex process, the Butex process remained in use at Windscale for primary decontamination of high-bumup fuel until the 1970s. Then an explosion, probably due to reaction of nitric acid vnth solvent, terminated its use. 

A solvent extraction process similar to Purex using TBP was developed by the Commissariat a I Energie Atomique [Gl] for use in the French plutonium separation plant at Marcoule. Since then, the Purex process has replaced the Butex process at Windscale [W3], has been used in the Soviet Union [Sll], India [S7], and Germany [S3], and by now is the universal choice for separation of uranium and plutonium from fission products in irradiated sUghtly enriched uranium. Fuel from the liquid-metal fast-breeder reactor (LMFBR) is also reprocessed by the Purex process, with modifications to accommodate the higher concentrations of plutonium and fission products. 

A number of other process applications of this class of extractants are worth mentioning at this point. 0,0 - dibutoxydiethylether ("Butex") has been used as one of the extractants, along with TBP in a two-solvent process for purification of Pu and recovery... 

Butex A process for separating the radioactive components of spent nuclear fuel by solvent extraction from nitric acid solution, using diethylene glycol dibutyl ether (also called Butex, or dibutyl carbitol) as the solvent. Developed by the Ministry of Supply (later the UK Atomic Energy Authority) in the late 1940s. Operated at Windscale from 1952 until 1964 when it was superseded by the Purex process. 

Thorex [Thorium extraction] A process for separating the products from the nuclear breeder reaction in which uranium-233 is produced by the neutron bombardment of thorium-232. It uses solvent extraction into tri-n-butyl phosphate. Developed at the Oak Ridge National Laboratory, TN, in the early 1960s. See also Butex, Purex, Redox. 

Redox [Reduction oxidation] A process for separating the components of used nuclear fuel by solvent extraction. It was the first such process to be used and was brought into operation at Hanford, WA, in 1951, but was superseded in 1954 by the Purex process. The key to the process was the alternate reduction and oxidation of the plutonium, hence the name. The solvent was Hexone (4-methyl-2-pentanone, methyl wobutyl ketone), so the process was also known as the Hexone process. The aqueous phase contained a high concentration of aluminum nitrate to salt out the uranium and plutonium nitrates into the organic phase. The presence of this aluminum nitrate in the wastes from the process, which made them bulky, was the main reason for the abandonment of the process. See also Butex. 

The first plant was based on the Butex solvent extraction process, operated in packed countercurrent columns, and used gravity flow for the highly active cycles which in turn led to a 250-ft-high building. 

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