Anenburg, MichaelLe Losq, Charles2019-04-022523-3963http://hdl.handle.net/1885/158136Perrhenate sodalite (Na8Al6Si6Re2O32) which contains the perrhenate anion (ReO4−) has been synthesised in equilibrium with Na–Fe-rich aluminosilicate melt and Re metal at 1100 °C and 500 MPa. Quenched glasses contain a homogeneous distribution of nepheline and magnetite, whereas sodalite only forms a crust on noble metal surfaces (Pt, Pt–Rh, Ag–Pd, and Re) in contact with the glass. The sodalite have been characterised by wavelength-dispersive X-ray spectroscopy and Raman spectroscopy. The experimental products contain both Re(0) and Re(VII), but other oxidation states of Re were not detected, suggesting the role of Na as a higher oxidation state stabiliser. Sodalite has potential uses for immobilising volatile Re and Tc during nuclear waste vitrification. Our study demonstrates the thermodynamic stability of perrhenate sodalite at Na-rich aluminosilicate melts at high temperature and pressure conditions.This work was supported by Australian Research Council grant FL130100066 to Hugh O’Neill.7 pagesapplication/pdfen-AU© Springer Nature Switzerland AG 2019PertechnetateMicroporousMesoporousZeoliteExperimental petrologyOptical basicity2019-0410.1007/s42452-019-0414-7