Atomic Energy Society of Japan

Decontamination of contaminated water containing radionuclides (Cs⁺, Sr²⁺, Mn²⁺, Zn²⁺, Co²⁺, Fe³⁺) is necessary in the decommissioning process. The Na-P1 type zeolite for adsorption of these metals was synthesized using coal fly-ash, and also chemical regents for comparison. These zeolites were heat-treated for the immobilization of the adsorbed metal ions in the decomposed zeolite. Another important issue is how to preserve the zeolite with adsorbed radionuclides, which can be suppressed by calcination, especially for FA-Na-P1. When Zn²+ is adsorbed, sintering reveals that it reacts with iron contained as impurities in coal incineration ash to form ZnFe₂O₄.