procedures for the control of plutonium in apatit ceramics and products derived from them

摘要

A phosphosilicate apatite useful as a confinement matrix for radioactive waste, and having the formula:wherein:M represents an alkaline metal,Ln represents at least one cation selected from lanthanides, andt, x, y, z, w and u are such that:0=t=1,8=x=10,0=y=1,0z=0.5,0=w=z, and0u=y+2z,and the total number of positive charges provided by the alkaline metal, Ca, Ln, Hf and Pu cations are equal to 20+u is prepared by a sintering-reaction of a mixture of reagent powders, in a neutral or reducing atmosphere, with application of pressure before or during sintering.