Low temperature upcycling of vitreous byproduct of the MSW plasma processing into multifunctional porous glass-ceramics

Mixtures of glass residues, deriving from the plasma processing of municipal solid waste (‘Plasmastone’), and recycled glasses have been already converted into highly porous glass-ceramics by application of an inorganic gel casting technique (foaming, by intensive mechanical stirring, of alkali activated slurries) followed by sintering at 1000°C. The full potential of recycled glass, however, has not been disclosed yet. The present investigation, in fact, demonstrates that boro-alumino-silicate glass, from discarded pharmaceutical vials, may allow for sintering of cellular glass-ceramics at particularly low temperature, i.e. at 800°C. The full stabilisation of heavy metals from Plasmastone (already assessed for treatments at 1000°C) is not compromised, whereas the low processing temperatures favour the separation of magnetite, in turn imparting new functionalities (e.g. electromagnetic shielding) to waste-derived glass-ceramic foams.