IMMOBILISATION METHOD OF RADIONUCLIDES OF ALKALINE-EARTH AND RARE-EARTH ELEMENTS IN MINERAL MATRIX Russian patent published in 2012 - IPC G21F9/16 

FIELD: power industry.

SUBSTANCE: immobilisation method of radionuclides of alkaline-earth and rare-earth elements in mineral matrix on the basis of reactions of metasomatic substitution in "wet" conditions differs by the fact that it involves the following: passage of nitrate solution of the above radionuclides through the column filled with particles of minerals with sizes of 0.40÷0.63 mm of model granite mixture or natural granite with crystalline water-free sodium orthophosphate, at mass ratio of sodium orthophosphate to the mixture which is equal to 1:3÷4; dehydration of the contents of the column by heating from room temperature to 400°C; saturation of the column contents with liquid sodium silicate with silica modulus equal to 2; the next annealing of the obtained mineral composition at temperature of 900-1250°C and atmospheric pressure, or hot pressing at temperature of 815-900°C and axial pressure of not more than 700 kg/cm² till crystalline mineral matrix containing the radionuclide phosphate is obtained.

EFFECT: invention allows optimising the method that allows reliable fixation of radionuclides in crystalline mineral matrix.

4 cl, 2 dwg, 6 ex