Development of plutonium adsorbent utilizing fibrous activated carbon

In the fuel reprocessing special laboratory of Japan Atomic Energy Research Institute, about 200 g of pure plutonium has been recovered from the spent fuel of JRR-3. In order to develop the process for effectively processing its TRU-containing waste liquid, the development of inorganic plutonium adsorbent based on fibrous activated carbon (FAC) was begun. The reduction of waste volume can be expected by incinerating this absorbent, and it is suitable to process the nitric acid waste generated from the reprocessing. The manufacturing processes of the FAC are the making of the pitch for spinning from the raw material of coal pitch, the melting and spinning of the prepared pitch, making the pitch fibers infusible, and the activation of the infusible pitch fibers. The features of the FAC are wide specific surface area, high adsorption rate as innumerable micropores of 10-20A diameter exist on the fiber surface, and excellent formability. The equilibrium adsorption test of plutonium and the test of passing liquid through a column were carried out, and the testing conditions and the results are reported. The development of the cartridge for the engineering scale use was attempted, and the adsorption performance was tested. The incineration test of the cartridge was carried out, and the testing conditions and the results are reported. (K.I.)