Preparation and Properties of Foam Glass-ceramic from Diatomite

Abstract

The results of the study of raw mix preparation and foam glass-ceramics production using diatomite as a raw material were presented in the following article. A mixture of diatomite and 40% NaOH solution was subjected to heating at a constant temperature of 775 °C. Samples of foam glass-ceramic from diatomite with an average density of 290 - 580 kg/m³, compressive strength of 1.7 - 7.8 MPa and thermal conductivity of 0.08 - 0.14 W/(m·K) were obtained. The investigations have shown that the hydrothermal pretreatment of mixture at the temperature of 90 °C may lead to the acceleration of the leaching of amorphous SiO₂ from diatomite. It was discovered that the resulting soluble alkali silicates promote the process of foaming during heating and reduce the average density of the obtained samples. The optimal duration of the leaching process was estimated to be 30 minutes, which corresponds to the yield of SiO₂ equal to 42.5% by the weight of dry diatomite.

Keywords

diatomite / liquid glass / foam glass-ceramics

References

[1] Demidovich BK. Penosteklo[M]. Minsk: Nauka i tekhnika, 1975

[2] Manevich VE, Subbotin K Yu. Foam Glass and Problems of Energy Conservation[J]. Glass and Ceramics, 2008, 65: 105-108.

[3] Spiridonov Y A, Orlova LA. Problems of Foam Glass Production[J]. Glass and Ceramics, 2003, 6: 313-314.

[4] Bobkova NM, Barantseva SE, Trusova EE. Production of Foam Glass with Granite Siftings from the Mikashevichi Deposit[J]. Glass and Ceramics, 2007, 64: 47-50.

[5] Vereshchagin VI, Sokolova SN. Effect of Technological Parameters on the Properties of Granular Porous Crystal Glass Material Based on Zeolite-bearing Rock[J]. Glass and Ceramics, 2009, 66: 46-49.

[6] Fernandes HR, Tulyaganov DU, Ferreira JM. Preparation and Characterization of Foams from Sheet Glass and Fly Ash Using Carbonates as Foaming Agents[J]. J. Ceram. Int., 2009, 35: 229-235.

[7] Bernardo E, Cedro R, Florean M, Hreglich S. Reutilization and Stabilization of Wastes by the Production of Glass Foams [J]. J. Ceram. Int., 2007, 33: 963-968.

[8] Balayan MA, Balekaev AG. Properties of Siliceous Solutions Based on Ural Diatomites[J]. Glass and Ceramics, 1988, 45: 325-327.

[9] Hans R, Dorit B, Jörg T. Structural Evolution of Sodium Silicate Solutions Dried to Amorphous Solids[J]. J. Non-cryst. Solids, 2001, 293-295: 752-757.

[10] Raghvan S, Helfried N. Phase Evolution on Heat Treatment of Sodium Silicate Water Glass[J]. J. Non-cryst. Solids, 2008, 354: 896-900.

[11] Iler RK. The Chemistry of Silica: Solubility, Polymerization, Colloid and Surface Properties and Biochemistry of Silica[M]. New York: Wiley, 1979

[12] Lazutkina OR, Kazak AK, Temereva AA, Nedopolz SO. Prospects of Using Diatomite Material from the Sverdlovsk Region in Enameling Production[J]. Glass and Ceramics, 2006, 63: 97-99.

[13] Sokolovich VE. Rapid Method of Determining the Modulus of Sodium Silicate Solution[J]. Glass and Ceramics, 1963, 20: 471-472.