Glass manufacturing, chemicals used sodium carbonate

Although sodium carbonate is needed in the manufacture of glass, very little is found in nature. It is made using two very abundant chemicals, calcium carbonate (marble) and sodium chloride (salt). The process involves many steps, but the overall reaction is... 

IJmnate. Sodium uranate, uranium yellow, Na2U04, yellow solid, insoluble, formed by reaction of soluble uranyl salt solution and excess sodium carbonate solution. Used (1) in the manufacture of yellowish-green fluorescent glass, (2) in ceramic enamels, (3) as a source of uranium for chemical reactions. 

Uses of sodium carbonate. In its various forms, more than 3 million tons of soda are used annually. Approximately one-half of this amount is used in the production of other chemicals, about one-fourth is used in the manufacture of glass, and the remainder is used for a variety of purposes including the production of pulp and paper, soap, textile products, and petroleum. Appreciable quantities of sodium carbonate are also used in water softening. 

For many centuries, sodium carbonate has been recovered from the beds of dried lakes and inland seas. It is also found in the mineral trona, Na2C03 NaHC03 2H20, which is now the commercial source of the compound in the United States. Sodium carbonate ranks high on the list of chemicals most used, and the majority of it is used in the manufacture of glass. 

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... 

Glass production starts with a mixture of raw materials, which for glass manufacture often contain a high proportion of naturally occurring minerals (for example, sand and limestone). However, some industrial chemicals such as sodium carbonate (NaiCOs) and alumina (AI2O3) are also used. The mixture containing the raw materials in the... 

Sodium carbonate (called soda ash) is used in all kinds of industrial processes, including water treatment and the manufacture of soaps, detergents, medicines, and food additives. Today about half of all Na2C03 produced is used in the glass industry. Sodium carbonate ranks eleventh among the chemicals produced in the United States. For many years, Na2C03 was produced by the Solvay process, in which ammonia is first dissolved in a saturated solution of sodium chloride. Bubbling carbon dioxide into the solution precipitates sodium bicarbonate as follows ... 

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