Sodium Glass

An additional assumption is that diffusion is independent of other species in the glass matrix. This cannot be strictly true because interdiffusion of at least one additional species is necessary to maintain charge balance within the glass. Sodium is most likely to be the dominant interdiffusion ion, as has been demonstrated for Sr and Cs diffusion in rhyolite glass at higher temperatures (10) and as supported by rapid release rates of Na to solution found in the present study. Codiffusion of hydronium and alkali ions are ignored in the model. 

Used in manufacture of soap, glass, sodium salts, as a detergent and water softener... 

An extreme example of a glass that can be easily weathered is sodium silicate, also known as soluble silicate or, informally, waterglass. The sodium content in sodium silicate is so high that the glass can be dissolved in water and shipped as a liquid glass. Sodium silicate is used as an adhesive, cleaner, and protective coating material. 

ASTM definition of water glass sodium-silicate glass which is soluble in water. 

Colourless container glass Sodium-potassium crystal glass Lead crystal glass (24 % PbO) Simax (Pyrex) ... 

A large part of the sodium carbonate consumed (e.g. 50% in the USA) is utilized in the glass industry, of which ca. 40% is used in the manufacture of bottle glass. Sodium carbonate serves both as a raw material and as a flux for the glass melt to dissolve the sand (see Section 5.1.2.2). A further 19% is utilized in the manufacture of chemicals, of which ca. 10% is for the production of sodium phosphates, mainly pentasodium triphosphate, in addition to silicates (sodium metasilicate pentahydrate and sodium orthosilicate), sodium chromate, sodium dichromate, sodium hydrogen carbonate, sodium nitrate etc. About 13.5% is utilized in the soap and detergent industry and 2.5% in the paper and pulp industry. Small quantities of sodium carbonate are necessary in almost all industry... 

Use Paper pulp, detergents and soaps, plate and window glass, sodium salts, ceramic glazes, dyes. 

Silica gels, such as those in Fig. 6.6, are prepared by mixing solutions of water glass (sodium silicate with SiOj/NajO 3.22) and HCl. This is an example of condensation and produces (H0)3Si-0-Si(0H)j sols of about 1.5 nm at a pH of 6. Gelation times of 10 min result in gels so stiff they may be cm into cubes. The hydrogel has a pore volume of 2.0cm g and contains about 60%-70% H O. 

Another process developed by Bayer uses finely ground borosilicate glass, sodium and hydrogen ... 

Liquid glass (sodium silicate) pulverized silicate Not known Compaction Soil compaction (sub-base of contaminated soil)... 

A process was developed that is capable of transforming poorly durable sodium silicate glasses (12 to 21% Na20) into durable high silica glasses. Sodium hydrosilicates with up to 40%... 

From this we concluded that the replaced feldspar preparation was mostly a method for preparing hydrous silica containing a little alumina but substantially free of other metallic ions due to the extensive acid treatment to remove the alkali and calcium ions. We also concluded that purified silica hydrogel could be made less expensively from water glass (sodium silicate). 

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