Development of Magnetic Zeolites for the Purpose of Radionuclide Decontamination

Abstract

The decontamination of Cs in rice fields is necessary for the continuation of agriculture in the Fukushima prefecture. A composite material consisting of the Na-P1 type zeolite and magnetite was synthesized from the fly-ash and iron chlorides, because the magnetic collection was possible using this composite material after radioactive Cs⁺ ion adsorption. The existence of nano-sized magnetites in the polycrystalline zeolite (several micrometers) was confirmed by SEM and TEM observations. By mixing soil with the magnetized Na-P1, with the mass ratio of 10:1, in ammonium oxalate solution for 10 min, more than 80% of radioactive Cs was removed from soil. The composite powder material consisting of mordenite and nano-sized magnetite was also synthesized from a mixed slurry of the diatomite and nano-sized magnetite.