Published online by Cambridge University Press: 03 September 2012
Synroc ceramics were synthesized in an induction-heated cold crucible atlaboratory scale (1 kg) from an oxide mixture, and at industrial prototypescale (45 kg) from Synroc previously produced by sintering under load athigh temperature. After melting, both materials contained the major phasesof Synroc-C. The chemical durability of both melted materials, as determinedby static leaching of powder samples in initially pure water at 90°C with anSA/V ratio of 20000m−1, was equivalent to that of conventionalhot-pressed Synroc-C. Cerium, used in this investigation to simulate thepresence of tri-and tetravalent actinides, was found in steady-stateconcentrations on the order of 1 ppb (i.e. NL(Ce) ≤ 10−6 g·m−2). The concentration in the leachates was independent ofthe initial CeO2 content of the Synroc (at least up to 10 wt%);moreover, it is similar to the results obtained with hot-pressed Synroc-Cspecifically formulated for conditioning long-lived actinides.