The results of studying the effect of nontraditional additives, namely, metallic aluminum and zinc powders on the process of silicate and glass formation using polythermal and thermogravimetric analysis, are described. The specifics of the glass-melting process for decorative glasses using the nontraditional additives are considered.Decorite is a special class of decorative opacified glasses for architecture and construction simulating natural marble, jade, or agate [1].The guiding idea in developing new types of sheet glasses was to have their compositions as standardized as possible, i.e., as close as possible to the composition of industrially made sheet glass and to avoid toxic or scarce opacifying agents. Such compositions should ensure decorative qualities and a high degree of opacification together with good technological properties of glass melt suitable for high-efficiency mechanized technologies, including the float process.A fundamentally new solution in the synthesis of decorative glasses opacified through liquation due to sulfur sulfide ions is using metal powders as modifying additives.The production of new types of glasses based on the reference float-glass composition used in the industry and powder metals has certain technological peculiarities, since the decorative and opacifying properties of the glass melt are related to the presence of iron and zinc sulfurous compounds in the melt, whose formation depends on the redox potential of the batch, the sulfide level of the melt, and the technology of synthesis [2].The sulfidizing mechanism in general can be represented as a scheme (Fig. 1). As sodium sulfate Na 2 SO 4 is used as the main sulfur-bearing material, the reducing atmosphere just in the gas furnace is insufficient for the formation of sulfide S 2-. It is necessary to have reducing conditions inside the glass melt, since a reducing medium decreases the temperature of the beginning of sulfide formation and increases its yield [3].Powdered metallic aluminum introduced as a modifying reducing additive creates thermodynamically efficient sulfidizing conditions and provides a high reducing potential of the batch and a reducing melting regime. A significant advantage of aluminothermic reduction is the exothermic type of the reactions, since oxidation of aluminum is accompanied by a substantial heat release, which is significantly higher than in oxidation of other metals:Powdered metallic zinc introduced as the second modifying additive and as the main zinc-bearing component supports the reducing activity of powdered metallic aluminum and thus intensifies the reducing potential of the batch; moreover, having enhanced affinity to sulfur, it increases the sulfide level of the melt, preventing the volatilization and oxidation of sulfur and binding it in a stable compound of zinc sulfide [4].It is established that only the joint presence of metallic aluminum and zinc powders and sodium sulfate produces marble-like opacification, whereas an increase in the content of the sulfate component changes the ...
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