Combined effects of lithium and borate ions on the hydration of calcium sulfoaluminate cement
- CEA, DEN, DTCD, SPDE, F-30207 Bagnols-sur-Cèze cedex (France)
- LMCPA, Université de Valenciennes et du Hainaut Cambrésis, 59600 Maubeuge (France)
- Ecole des Mines de Douai, LGCgE-GCE, 59508 Douai (France)
This work investigates the combined influence of borate and lithium ions on the hydration of two calcium sulfoaluminate (CSA) cements containing 0 or 10 wt% gypsum. On the one hand, borates are known to retard CSA cement hydration due to the rapid precipitation of ulexite. On the other hand, lithium ions accelerate CSA cement hydration thanks to the fast precipitation of Li-containing aluminum hydroxide. When borates and lithium are present simultaneously, these two mechanisms are superimposed. With a gypsum-free cement, a third process is additionally observed: lithium promotes the initial precipitation of a borated AFm phase which is later converted into a borated AFt phase when hydration accelerates. Lithium salts can counteract the retardation by sodium borate. However, their influence is limited once a sufficient amount of Li-containing Al(OH){sub 3} seeds is formed. For the CSA cements under investigation, the threshold lithium concentration is close to 0.03 mmol/g of cement and similar with or without borate.
- OSTI ID:
- 22697115
- Journal Information:
- Cement and Concrete Research, Vol. 97; Other Information: Copyright (c) 2017 Elsevier Science B.V., Amsterdam, The Netherlands, All rights reserved.; Country of input: International Atomic Energy Agency (IAEA); ISSN 0008-8846
- Country of Publication:
- United States
- Language:
- English
Similar Records
Physico-chemical mechanisms involved in the acceleration of the hydration of calcium sulfoaluminate cement by lithium ions
Hydration of Portland cement with additions of calcium sulfoaluminates