The iodine species and their behavior in the dissolution of spent-fuel specimens

Journal Article · Wed Jul 01 04:00:00 EDT 1992 · Nuclear Technology; (United States)

OSTI ID:7296417

Sakurai, T; Takahashi, A; Komaki, Y; Ohnuki, M ^[1]

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1. Japan Atomic Energy Research Inst., Dept. of Chemistry, Tokai-mura, Ibaraki-ken 319-11 (JP)

In this paper, spent-fuel specimens ({approximately}3 g each) with a burnup of 21 to 39 GWd/t were dissolved in 30 ml of 4 M HNO{sub 3} at 100{degrees} C, and the distribution of iodine and its chemical forms in the solution were studied. A small quantity of the iodine was conveyed to the insoluble residue (up to 2.3%), some remained in the fuel solution (up to 9.7%), and the balance was in the off-gas. Iodine was not deposited on the fuel cladding. Organic iodides were only {approximately}6.5% or less of the total amount of iodine in the off-gas. The fuel solution included iodine species that were difficult to expel by NO{sub 2} sparging alone (27 to 46% of the iodine in the solution). These species were ascribed to be the colloids of AgI and PdI{sub 2}. Iodate (IO{sup {minus}}{sub 3}) was a rather minor iodine species in dissolution in {approximately}4 M HNO{sub 3}. A thermochemical calculation also supports these results, indicating that the quantity of IO{sup {minus}}{sub 3} is {le}1.7 {times} 10{sup {minus}4}% of the iodine fed to 4 M HNO{sub 3} and that the colloid of AgI can be formed when the concentration of I{sup {minus}} is {ge}5.3 {times} 10{sup {minus}10} M.

• OSTI ID: 7296417
• Journal Information: Nuclear Technology; (United States), Journal Name: Nuclear Technology; (United States) Vol. 99:1; ISSN 0029-5450; ISSN NUTYB
• Country of Publication: United States
• Language: English

Related Subjects

050700* -- Nuclear Fuels-- Fuels Production & Properties
050800 -- Nuclear Fuels-- Spent Fuels Reprocessing
11 NUCLEAR FUEL CYCLE AND FUEL MATERIALS
42 ENGINEERING
420400 -- Engineering-- Heat Transfer & Fluid Flow
CALCULATION METHODS
COLLOIDS
DATA
DIAGRAMS
DISPERSIONS
DISSOLUTION
ELEMENTS
ENERGY SOURCES
EQUILIBRIUM
EXPERIMENTAL DATA
FUELS
HALOGENS
HEAT TREATMENTS
INFORMATION
IODINE
MATERIALS
NONMETALS
NUCLEAR FUELS
NUMERICAL DATA
REACTOR MATERIALS
SPENT FUELS
THERMOCHEMICAL DIAGRAMS