Reaction of quartz glass in lithium-containing alkaline solutions with or without Ca

Abstract

The exact role of lithium ions (Li+) in controlling alkali–silica reaction is still unclear. Thus, the effects of Li+ on the reaction between reactive silica (quartz glass) and hydroxyl in alkaline solution with or without Ca were investigated by quartz glass powder or slice immersion experiments. When quartz glass was immersed in lithium-containing alkaline solutions, only Li2SiO3 was produced with the absence of Ca, but Li2SiO3 and calcium silicate hydrate (CSH) were formed with the presence of Ca. The quartz glass slice immersion experiment indicated that the mass loss of quartz slices was less than 1% only when Ca was present in the lithium-containing alkaline solution. This was because a dense, low-porosity and strongly bonded production layer mainly composed of CSH and Li2SiO3 crystals was formed on the glass surface and served as a barrier against the diffusion of OH− and alkali ions to the substrate glass.

Role of Aluminum and Lithium in Mitigating Alkali-Silica Reaction—A Review

“…In the presence of calcium, the effect of Li on the dissolutions changes drastically. A significant decrease in SiO 2 dissolution rate in 100 and 1,000 mM NaOH in the presence of both Li and Ca and the formation of a dense C-S-H containing Li were observed (Leemann et al, 2014;Zhou et al, 2018), indicating a destabilization of Li 2 SiO 3 in the presence of calcium. It has been speculated that this Li containing C-S-H layer is responsible for the slowdown of the silica dissolution in the presence of both Li and Ca.…”

“…Bagheri et al (2021) investigated the effect of Li + under high pH conditions (in 400 mM KOH) and found a clear acceleration of SiO 2 dissolution in the presence of Li + , which might be related to the ability of Li + to form surface complexes on silica. It should be noted that lithium can precipitate in the presence of silica as Li 2 SiO 3 (Zhou et al, 2018;Bagheri et al, 2021), which can lower the measured silicon concentration or mass loss in dissolution experiments (Kurtis and Monteiro, 2003;Tremblay et al, 2010;Leemann et al, 2014;Zhou et al, 2018;Oey et al, 2020;, leading to an apparent decrease in the observed dissolution rate. In the presence of calcium, the effect of Li on the dissolutions changes drastically.…”

“…The detailed study of the literature has indicated that Li might somewhat accelerate SiO 2 dissolution, but only in the absence of calcium, while in the presence of Ca and Li a clear decrease of the silica dissolution has been observed (Leemann et al, 2014;Zhou et al, 2018), which might contribute together with other factors to the lower the expansion observed for Li containing concretes.…”

“…Due to the lack of characterizations of the chemical composition and molecular structure, the amorphous Li-Si products are often described as "Li-Si complex" following the work of Lawrence and Vivian (1961). In some cases, also the precipitation of crystalline Li-containing products has been observed (Mo et al, 2003;Collins et al, 2004a;Feng et al, 2010), generally Li 2 SiO 3 , which seems to form in the absence of Ca and at low Ca but high Li contents (Zhou et al, 2018;Bagheri et al, 2021). However, so far no systematic investigations about the formation conditions of the amorphous and crystalline Li-containing products have been conducted.…”

Effect of LiNO3 on Expansion of Alkali–Silica Reaction in Rock Prisms and Concrete Microbars Prepared by Sandstone

“…Through MR experiments, Kim T [21] showed that the most likely mechanism to explain the excellent ability of Li+ ions to inhibit ASR involves the dense physical barrier, which is formed by the reaction products covers delimited areas on the exposed surface of the reactive aggregate. Zhou BF [22] found that quartz glass slices immersed in the alkaline solution with LiNO 3 and Ca(OH) 2 were well protected by a production layer consisting of Li 2 SiO 3 crystals and CSH that densely and firmly covered the surfaces of samples, but seriously corroded in solutions with only LiNO 3 or Ca(OH) 2 .…”