Continuous plutonium(IV) oxalate precipitation, filtration, and calcination process. [From product streams from Redox, Purex, or Recuplex solvent extraction plants]

Technical Report · Thu Sep 27 04:00:00 EDT 1956

DOI:https://doi.org/10.2172/7227473· OSTI ID:7227473

Beede, R L

A continuous plutonium (IV) oxalate precipitation, filtration, and calcination process has been developed. Continuous and batch decomposition of the oxalate in the filtrates has been demonstrated. The processes have been demonstrated in prototype equipment. Plutonium (IV) oxalate was precipitated continuously at room temperature by the concurrent addition of plutonium (IV) nitrate feed and oxalic acid into the pan of a modified rotary drum filter. The plutonium (IV) oxalate was calcined to plutonium dioxide, which could be readily hydrofluorinated. Continuous decomposition of the oxalate in synthetic plutonium (IV) oxalate filtrates containing plutonium (IV) oxalate solids was demonstrated using co-current flow in a U-shaped reactor. Feeds containing from 10 to 100 g/1 Pu, as plutonium (IV) nitrate, and 1.0 to 6.5 M HNO/sub 3/, respectively, can be processed. One molar oxalic acid is used as the precipitant. Temperatures of 20 to 35/sup 0/C for the precipitation and filtration are satisfactory. Plutonium (IV) oxalate can be calcined at 300 to 400/sup 0/C in a screw-type drier-calciner to plutonium dioxide and hydrofluorinated at 450 to 550/sup 0/C. Plutonium dioxide exceeding purity requirements has been produced in the prototype equipment. Advantages of continuous precipitation and filtration are: uniform plutonium (IV) oxalate, improved filtration characteristics, elimination of heating and cooling facilities, and higher capacities through a single unit. Advantages of the screw-type drier-calciner are the continuous production of an oxide satisfactory for feed for the proposed plant vibrating tube hydrofluorinator, and ease of coupling continuous precipitation and filtration to this proposed hydrofluorinator. Continuous decomposition of oxalate in filtrates offers advantages in decreasing filtrate storage requirements when coupled to a filtrate concentrator. (JGB)

• Research Organization: Battelle Pacific Northwest Labs., Richland, WA (USA); Hanford Site (HNF), Richland, WA (United States)
• Sponsoring Organization: Not Available; USDOE Office of Environmental Management (EM)
• DOE Contract Number: W-31-109-ENG-52
• OSTI ID: 7227473
• Report Number(s): HW-45700
• Country of Publication: United States
• Language: English

Related Subjects

050800* -- Nuclear Fuels-- Spent Fuels Reprocessing
11 NUCLEAR FUEL CYCLE AND FUEL MATERIALS
ACTINIDE COMPOUNDS
CALCINATION
CARBOXYLIC ACID SALTS
CARBOXYLIC ACIDS
CHALCOGENIDES
CHEMICAL REACTIONS
DECOMPOSITION
DICARBOXYLIC ACIDS
ENERGY SOURCES
FILTRATION
FUELS
NITRATES
NITROGEN COMPOUNDS
NUCLEAR FUELS
ORGANIC ACIDS
ORGANIC COMPOUNDS
OXALATES
OXALIC ACID
OXIDES
OXYGEN COMPOUNDS
PLUTONIUM COMPOUNDS
PLUTONIUM DIOXIDE
PLUTONIUM NITRATES
PLUTONIUM OXIDES
PRECIPITATION
PRODUCTION
PUREX PROCESS
PYROLYSIS
REACTOR MATERIALS
REDOX PROCESS
REPROCESSING
SEPARATION PROCESSES
SPENT FUELS
THERMOCHEMICAL PROCESSES
TRANSURANIUM COMPOUNDS