Use of Sodium Silicate Gel as Precursor of Binder for Cold Consolidated Materials

Abstract:

Consolidation of cements and geopolymers can be explained by the formation of alkali silicate or alumino-silicate gels formed in situ during materials setting. To control such a system, a study concerning the use of sodium silicate gel as binder was initiated to manufacture consolidated materials with different size distribution of silica. The gels used as precursor of binder were synthesised by acidifying with hydrochloric acid, a concentrated sodium silicate. Consolidated materials were obtained by mixing the previous solution before gelation with granular materials (fine silica powder and sands). The existence domain of consolidated materials depends on the size distribution of sand. Consolidation of material is strong when the amount of silica is high. This result suggests a dissolution / precipitation reaction between gel and silica. Therefore, consolidation could be explained by the dissolution of small particles of silica and their precipitation into the grain boundary of sand. Mechanical properties are closed to those of cement materials.

• Periodical: Advances in Science and Technology (Volume 69)
• Pages: 57-62
• DOI: https://doi.org/10.4028/www.scientific.net/AST.69.57
• Online since: October 2010
• Authors: Monique Tohoué Tognonvi, Séka Simplice Kouassi, Toyotaka Maeda, Julien Soro, Sylvie Rossignol, Jean Pierre Bonnet
• Keywords: Concentrated Sodium Silicate Solution, Consolidated Material, Dissolution-Precipitation, Shrinkage, Ternary Diagram

References

[1] J.W. Phair and J.S.J. Van Deventer: Characterisation of fly ash-based Geopolymers activated with sodium aluminate. Ind. Eng. Chem. Res., vol. 41 (2002), p.4242.

DOI: 10.1021/ie010937o

[2] J.W. Phair, J.S.J. Van Deventer and J.D. Smith: Mechanism of polysialation in the incorporation of zirconia into fly ash-based geopolymers. Ind. Eng. Chem. Res., vol. 39 (2000), p.2925.

DOI: 10.1021/ie990929w

[3] H.E. Bergna and W.O. Roberts: in Colloidal silica: fundamentals and applications, edited by CRC Press Taylor and Francis Group, Wilmington (2006).

[4] K. Yamada, T. Hashimoto and Y. Furumi, Ceramics, vol. 11 (1976), p.785.

[5] K. Sangwal, B. Wiktorowska and T. Sokolowski in: Elementary Crystal Growth, edited by Saan Pub., Lublin (1994).

[6] M.T. Tognonvi, in: Physico-chimie de la gélification du silicate de sodium en milieu basique. PhD thesis, University of Limoges, France, (2009).

[7] R.K. Iler, in: The Chemistry of Silica, edited by John Wiley and Sons, New York (1979).

[8] K.G. Knauss and T.J. Wolery: The dissolution kinetics of quartz as a function of pH at 70°C. Geochem. Cosmochim. Acta, vol. 52 (1987), p.43.

[9] J.H. Henderson, J.K. Syers, M.L. Jackson, Quartz dissolution as influenced by pH and the presence of a disturbed layer,. Israel J. Chem., vol. 8 (1970), p.357.

DOI: 10.1002/ijch.197000042

[10] M. Mgaidi, F. Jendoubi, D. Oulahna, M. El Maaoui and J.A. Dodds: Kinetics of the dissolution of sand into alkaline solutions: application of a modified shrinking core model. Hydrometallurgy, vol. 71 (2004), p.435.

DOI: 10.1016/s0304-386x(03)00117-8

[11] J.A. Van Lier, P.L. De Bruyn and J. Th.G. Overbeek: The solubility of quartz. J. Phys. Chem., vol. 64 (1960), p.1675.