Development of the thermogravimetric analysis method using microwave heating and its application

Segawa, Tomoomi; Hamaba, Taishu*; Yoshida, Hideto*; Fukui, Kunihiro*

no journal, , 

In the field of reprocessing of spent nuclear fuel, the aqueous solution of uranyl nitrate and plutonium nitrate is converted to the mixed oxide powder (MOX raw powder) using the microwave heating method for direct denitration. In order to clarify the reaction mechanism of denitration of a metallic nitrate aqueous solution using microwaves, the novel thermogravimetric analysis unit using microwave heating was developed. The absorbed microwave energy can be measured by 2 power meters set on the both side of the raw material. The change in the temperature and the mass of the raw material can be also measured continuously. The process for synthesizing metallic oxide powders by the microwave denitration method was investigated using trihydrated copper nitrate aqueous solutions with this apparatus. As a result of this study, it was found that the reaction routes for microwave heating are the same as those for conventional external heating.