Solidification material of radioactive iodine and solidification method therefor

In the present invention, there are used a cement solidification material comprising from 15 to 17% of alumina cement and the balance of Ca-compounds, a solidification material comprising from 20 to 90% of a cured pulverization product of alumina cement and the balance of Ca-compounds or a solidification material comprising from 20 to 80% of Ca aluminate and the balance of Ca-compounds (on the weight basis). The material easily forms a cured product of radioactive wastes which is greatly adsorptive especially to radioactive iodine thereby capable of solidifying radioactive iodine and forming it into a compound stable for a long period of time. (T.M.)