Corrosion Mechanism in the Obsidian and its Comparison with the Nuclear Waste Glass for Long-Term Performance Assessment in the Geological Repository

摘要: Present paper discusses experimental work on obsidian glass to understand corrosion mechanism at variable pressure temperature conditions. For comparison, Advanced Vitrification System, a nuclear waste was studied simultaneously under similar Owing massive weight loss the samples were unable sustain beyond 4 hour during experiments. Corrosion experiments both these glasses performed hydrothermal like conditions and observed that changes in have major control over release of sodium other ions from glass, hence effecting mechanism. X-ray diffraction patterns residue obtained after revealed appearance neo-formed minerals, such as quartz, celadonite, halloysite, sodalite, heulandites wairakite. High degree formation amorphous case 300 0 C granules glass. The back scattered electron images scanning microscope indicate distinctive microstructures, associated with their is linked sodium, potassium ions, causing pH conductivity leachate. In indicates multiple alteration layers secondary products. surface pellet experiment shows phyllosilicate numerous tiny spherules embedded within structure. These results when extrapolated suggest silica, quartz chalcedony end members whereas, iron rich fayalite greenalite can be mechanism, minerals stability been discussed paper.