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Journal articles
Titanium in ground-granulated blast-furnace slag-like calcium-magnesium-aluminosilicate glasses: Its role in the glass network, dissolution at alkaline pH and surface layer formation
Abstract : Small TiO2 contents in the slag-glass significantly reduce their cementitious reactivity. We investigated the role of Ti in the glass network and its influence on slag-glass dissolution. XANES and EPR analysis showed that 67% of Ti as Ti(IV) with about 70% in [5] Ti and 30% in [4] Ti coordination, and 33% as Ti(III). The presence of Ti had only a minor impact on initial dissolution rates at pH 11 (R ≈ 10-6 molglass.s-1 .m-2). During dissolution, Ti accumulated in an amorphous layer at the glass-surface. Ti-coordination in this layer was 50% [5] Ti and 50% [6] Ti. At pH 11, the layer was mainly composed of TiO2 (66 wt%), but intermixed with a hydrotalcitelike phase at pH 13. The loss of cementitious reactivity in the presence of Ti appears to be not only due to stabilization of the glass structure but also to the formation of a Ti-rich surfacelayer, that may become passivating.
https://hal.archives-ouvertes.fr/hal-03689510
Contributor : Simon Blotevogel Connect in order to contact the contributor
Submitted on : Tuesday, June 7, 2022 - 12:10:25 PM
Last modification on : Monday, July 4, 2022 - 9:00:44 AM
Contributor : Simon Blotevogel Connect in order to contact the contributor
Submitted on : Tuesday, June 7, 2022 - 12:10:25 PM
Last modification on : Monday, July 4, 2022 - 9:00:44 AM