[en] A soluble iron salt is added to the liquid radioactive waste so that the resulting iron concentration should be 0.02 - 0.5 mol in 1 dm³. The pH is adjusted with sodium hydroxide to a value of 8 - 13. The solution is then boiled for 5 to 30 mins. Granulated iron may be added (grain size 0.05 - 1 mm) to the amount of 0.05 - 1g/l of solution. After cooling to at least 25 degC, the solution is subjected to a magnetic field with an intensity of 2.10³ to 4.10⁵ A.m^-1. The precipitate of hydrated iron oxides traps impurities, radioactive isotopes and non-ferromagnetic impurities. The liquid radioactive wastes need not be distilled and after cleaning they may be raused. (Pu)