Radwaste Immobilization by Structural Modification—the Crystallochemical Properties of SYNROC, a Titanate Ceramic

Authors

  • Dr. Timothy J. White,

    Corresponding author
    1. School of Science, Griffith University, Nathan, Brisbane, Queensland 4111 (Australia)
    Current affiliation:
    1. Australian Atomic Energy Commission, Lucas Heights Research Laboratories, Private Mail Bag, Sutherland NSW 2232 (Australia)
    • School of Science, Griffith University, Nathan, Brisbane, Queensland 4111 (Australia)
    Search for more papers by this author
  • Robert L. Segall,

    1. School of Science, Griffith University, Nathan, Brisbane, Queensland 4111 (Australia)
    Search for more papers by this author
  • Peter S. Turner

    1. School of Science, Griffith University, Nathan, Brisbane, Queensland 4111 (Australia)
    Search for more papers by this author

Abstract

New studies utilizing electron microscopic techniques have revealed the immobilization of radionuclides in crystalline ceramic waste forms to be not merely a question of substituting waste elements into the appropriate crystallographic sites of a host matrix. Rather than entering the ceramic as a “continuous” solid solution it has been found that the incorporation of highly radioactive waste elements is commonly accompanied by structural modification. This may take the form of cation ordering, crystallographic shear, or twinning on a unit cell scale. Such mechanisms considerably enhance the capacity of a ceramic to immobilize (simulated) radwaste and impart to it the flexibility to respond to inevitable variations in wastestream composition.

Ancillary