Leaching of strontium from strontium-doped pyrochlore for nuclear waste disposal studies

With the development of advanced and newer generation reactors, the problem of safe disposal of nuclear waste has become more acute. The Vitrification i. e. the incorporation of radioactive waste in glass cannot hold it for more than 100 years. The glasses are thermodynamically unstable and undergo devitrification which poses a danger of radionuclides leaching out to the environment. Crystalline materials with the pyrochlore structure have been suggested as candidates for the immobilisation of actinide species found in high-level nuclear waste (HLW) streams from the nuclear power industry and weapons decommissioning programmes. The resilience of these crystalline ceramics to intrinsic radiation damage and degradation by repository groundwater is far better than that of the borosilicate glasses. Various pyrochlore oxides of the type A2B2O7 like Nd2Zr2O7, Gd2Zr2O7, Gd2Ti2O7 have been studied widely as a matrix for nuclear waste disposal