Effect of Precipitation Conditions on the Specific Surface Area of Neptunium Oxide

HILL, BENJAMINC.

Savannah River Site (S.C.)

关键词: Calcination;    Flowsheets;    Surface Area;    Specific Surface Area;    Neptunium;   

DOI  :  10.2172/829838
RP-ID  :  WSRC-TR-2004-00296
RP-ID  :  AC09-96SR18500
RP-ID  :  829838

美国|英语

来源: UNT Digital Library

【 摘 要 】

Neptunium oxalate was precipitated under nominal and bounding HB-Line flowsheet conditions. The nominal case represents expected normal HB-Line operation. The bounding case represents process flowsheet extremes that could occur which are anticipated to decrease particle size and increase surface area. The neptunium oxalate produced under bounding conditions was used to validate the effectiveness of HB-Line calcination conditions. The maximum specific surface area of the neptunium oxide (NpO2) used in gas generation testing was 5.34 m2/g. Experiments were conducted to verify that even under bounding precipitation conditions the SSA of NpO2 produced would remain within the range evaluated during gas generation testing. The neptunium oxalate from nominal and bounding precipitation conditions was calcined at 600 degrees Celsius and 625 degrees Celsius, respectively, to form NpO2. Samples from each batch of neptunium oxalate were calcined for one, two, or four hours. Results indicate that the SSA of NpO2 continues to decrease between one and four hours. After two hours of calcination at 625 degrees Celsius, the SSA of NpO2 from the bounding case meets the surface area requirements for limiting moisture uptake.