Application of the Flotation Method for the Treatment of the Waste Solution in the Chemical Processing of Used Nuclear Fuel : Selective Removal of Mixed Fission Products

Abstract

As a part of the fundamental study on the treating of the liquid wastes in the chemical processing of used nuclear fuel, the preferential flotation was investigated for the selective removal of the long-lived fission products such as ¹³⁷ Cs, ⁹⁰Sr, ¹⁰⁶Ru, +1⁴⁴Ce and ⁹⁵Zr from the low or intermediate level radioactive solutions. By three stage preferential flotation using sodium oleate or octadecylamine acetate as the collector and cupric ferrocyanide or ferric hydroxide as the coprecipitant, 95% of ¹³⁷Cs, 87% of ⁹⁰Sr, and above 98% of the mixture of¹⁴⁴Ce, ¹⁰⁶Ru and ⁹⁵Zr were removed respectively from the radioactive solution. The whole amount of the resulting radioactive sludge per 1000 ml of the original radioactive solution was 130～190 mg.