Low Temperature Glass Sintering Based on Silico Sodium Resins
Abstract
By using silicate inorganic binders and glass waste it is possible to mould technical and artistic elements which later can be compacted by means of low temperature, and subsequently apply the sintering through high-temperature processing, which is generally lower than current melting glass processes, close to 1250 °C. The experimental phase established thermal ranges from 600°C to 750°C, a fact that allows for an effective sintering temperature (of around 650°C/18 hours). The mixtures and proportions for this experiment were fixed including ethyl silicate as a fluidizer in mixtures,as well as the size of glass grains.The results indicate good compaction of the samples after the initial phase (80°C/24h), allowing proper handling without alterations in samples edges.During heating treatment, mechanical resistance increases gradually (600-750°C), although the volume of porosity was inversely proportional. According to the matrix vs grain size relationship, the partial fusion of both materials is evident in the rounding of the glass grains as well as the resin bonds joined between them. The resins appeared in a homogenous fashion, covering and gluing the grains, a development which improves the joining of sintered samples. Samples with a mixture of sodium silicate and ethyl silicate resins experienced less melting between grains due to a lower volume of fluxing elements, which means a lower percentage volume of sodium (Na). This study concludes that a sintering process for new vitreous composites could be carried out between 650°C and 700°C, offering the opportunity for a substantial reduction in the amount of energy required to produce industrial glass.
Keywords: Water-glass, glass recycling, low temperature
References
[1] Provis, L. and van Deventer, J.S.J. (eds.) (2009). Geopolymers: Structures, Processing, Properties and Industrial Applications. (Cambridge: Woodhead Publishing).
[2] vanDeventer,J.S.J.,Provis,L.,andDuxson,P.(2012).Technicalandcommercialprogressintheadoption of geopolymer cement. Miner. Eng., vol. 29, pp. 9-104.
[3] Turner, L. and Collins. F. (2013). Carbon dioxide equivalent (CO2-e) emissions: A comparison between geopolymer and OPC cement concrete. Const. & Build. Mat., vol. 43, 125-130
[4] Villegas, M. A., et al. (2017) The glass sculpture. (Granada: University of Granada), p.350.
[5] Sáez-Pérez, M.P., et al. (2019). New low temperature glass composites from glasses recycling, applied for architectural conservation. 4th International Conferenceon Technological Innovation in Building6-8 March 2019, Madrid, pp. 260-262
[6] Mohajerani, A., et al. (2019). Recycling waste materials in geopolymer concrete. Clean Techn Environ Policy vol. 21, pp. 493–515.
[7] Rashidian-Dezfouli,H.,andRangaraju,P.R.(2017).Comparisonofstrengthanddurabilitycharacteristics of a geopolymer produced from fly ash, ground glass fiber and glass powder. Materiales de Construcción, vol. 67, http://dx.doi.org/10.3989/mc.2017.05416
[8] Torres-Carrasco, M., and Puertas, F. (2015). Waste glass in the geopolymer preparation. Mechanical and microstructural characterisation, J. Clean. Product., vol. 90, pp. 397–408.
[9] Rivera,J.F.,et al.(2018).Noveluseofwasteglasspowder:Productionofgeopolymerictiles.Advanced Powder Technology vol. 29 pp. 3448-3454.
[10] Puertas, F., Torres-Carrasco, M., and Alonso, M.M., (2015). Handbook of Alkali-Activated Cements, Mortars and Concretes. (Paris: Elsevier).
[11] Torres-Carrasco, M., Palomo, J.G., and Puertas, F. (2014). Disoluciones de silicato sódico procedentes del tratamiento de residuos vítreos. Estudio estadístico, Materiales de Construcción, vol. 64, issue 14, https://doi.org/10.3989/mc.2014.05213.