| 摘要 |
PURPOSE: To accelerate melting and removing of a radioactive nuclide by a method wherein a process of changing a state and a condition of the radioactive nuclide in a titanium iron material is carried out, and then it is leached with an acid. CONSTITUTION: When a material is processed to change a state of a radioactive nuclide in a titanium iron material for later more effective acid leaching, a radioactive removal from the material is greatly enhanced. A base is used for the process from conditions of preventing substantial elution of iron and titanium. Further, it is desired that the leached radioactive nuclide from the titanium iron material is separate by filtering or cyclone separation. As a base, a compound of an alkali metal and an alkali earth metal may be used, or it may be caustic soda or caustic potash. A mineral acid is preferable for acid- leaching, and particularly sulfuric acid is preferable. As for the titanium iron material, ilmenite, modified ilmenite or the like is preferable. The removed nuclide preferably contains a thorium or uranium radioactive nuclide. Thus, a removal of the radioactive nuclide from the titanium iron material can be accelerated. |
