Issue
Korean Journal of Chemical Engineering,
Vol.17, No.2, 217-222, 2000
A Photo-induced Dissolution of UO2 Sintered Pellets in a Simulated Solution
The objective of this study is to improve the established dissolution technique of UO2 target by using a photochemical reaction. Photo-dissolution tests of UO2 sintered pellets were carried out in a simulated nitric and solution at about 50℃ under UV irradiation. The simulated solution consists of 2 M nitric acid containing elements such as Cs, Sr, Zr, Ru, Mo and Nd. The light source is a Hg-lamp emitting 254 nm wavelength. As results, in the dark reaction, UO2 sintered pellets were hardly dissolved, whereas UO2 was rapidly dissolved after 7 hours of dissolution time in the UV irradiation. The very low dissolution rate in the dark reaction was due to surface characteristics of sintered pellets : UO2 sintered pellets is very dense and has extremely low specific surface area. However, the dissolution rate of UO2 sintered pellet was considerably increased in the simulated solution under UV irradiation. This was attributed to the fact that ruthenium and molybdenum ions in the simulated solution could accelerate the dissolution of UO2 under UV irradiation. Additionally, when the pulverized sintered UO2 powder was used, the dissolution rate of UO2 increased more rapidly than that of UO2 sintered pellet.
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