FABRICATION OF TRANSMUTATION AND INCINERATION TARGETS BY INFILTRATIONOF POROUS PELLETS BY RADIOACTIVE SOLUTIONS

Infiltration of metal nitrate solutions into porous pellets, followed by thermal conversion of the nitrate to oxide and sintering of the pel lets, provides an alternative procedure for the fabrication of targets for the transmutation and incineration of actinides and fission produ cts. The infiltration rate of metal (Ce and Pu) nitrate solutions into porous spinel (MgAl2O4) pellets depends on the viscosity of the solut ion, while the infiltrant content depends on the solution concentratio n and the pellet porosity. The infiltration depth is proportional to t he square root of the time the pellet is immersed in the solution. Tai lored distributions of the infiltrant can be achieved either by select ing the immersion time, or by applying an impenetrable coating on sele cted regions of the pellet surface. (C) 1998 Elsevier Science S.A.