Title : Sims profiles of alteration films formed on the surface of alkali-resistant glass in acidic and basic environments
Abstract:
The aim of this study is to analyze in depth the elemental profiles of the alteration films formed on the altered surface of alkali-resistant zirconiumcontaining glasses in acidic and basic environments, using secondary ion mass spectroscopy (SIMS) or ion probe. For this, we have developed 5 glass compositions: V1 (with zirconium and without heavy metals) and V2 (with zirconium and heavy metals), then three glasses of fly ashes V3 (without zirconium and with heavy metals), V4 (with 30% of V3, zirconium and heavy metals) and V5 (with 60% of V3, zirconium and heavy metals). SIMS profiles obtained on the alteration layers of glasses V1, V2, V3, V4, and V5 using the ion probe made it possible to observe the behavior of the elements H, Na, K, Ca, Si, and Zr at 28 days and at pH=4 and 13, and to understand the different dissolution mechanisms involved. At pH=4 and 13, the profiles showed that a hydrated layer developed on the surface and was characterized by an enrichment in hydrogen H and a depletion in sodium Na regardless of the glass. These 5 glasses were also characterized by a surface enrichment in zirconium (except V3, which did not contain zirconium) regardless of the pH. Other elements behaviour (K, Ca, and Si) was strongly linked to the glass composition. SIMS profiles highlighted the low hydration of glasses V4 and V5 compared to the other glasses and confirmed the enrichment of the alteration layers in zirconium and their depletion in Na.
