Published online by Cambridge University Press: 03 September 2012
Synroc containing 20 wt% simulated high level waste (HLW) was subjected totwo sets of leach tests at 150°C where the leachant was and was not replacedduring the test (replacement and non-replacement testing). The leachant wasa KH-phthalate buffered solution (pH 4.2). Samples were characterised beforeand after leach testing using SEM, AEM and SIMS. Elemental concentrations inleachates were measured using ICP-MS. In concert with the findings of i) adissolution study of perovskite in a flowing leachant and ii) a previousSynroc dissolution study (wherein Synroc containing 10 wt% simulated HLW wassubjected to periodic replacement, leach testing in deionised water at150°C), the results of this study show that when the leachant replacementfrequency is varied from 7 d to the duration of the test, there is no effecton leach rate or leaching mechanisms.