Carbonato de sódio

O carbonato de sódio (CAS 497-19-8) é um sal inorgânico branco, inodoro, cristalino ou em pó, higroscópico e altamente solúvel em água, com ponto de fusão de aproximadamente 851 °C. Classificado quimicamente como um sal de carbonato alcalino, apresenta forte caráter básico em solução aquosa devido à hidrólise do ânion carbonato. É amplamente empregado como matéria-prima essencial na fabricação de vidro, sabões e detergentes, além de atuar como agente regulador de pH, amaciante de água e neutralizante em processos industriais. Seu uso abrange setores estratégicos como a indústria química, de tratamento de águas, de papel e celulose, bem como na síntese de outros compostos inorgânicos, como o bicarbonato de sódio e diversos fosfatos.

Sodium carbonate is a kind of important raw material for chemical industry with wide application. It is the important raw material for making glass, soaps, detergents, textiles, leather, spices, dyes, medicines, etc. It can be used for analysis reagents and also used for the pharmaceutical industry and photoengraving. It is widely used in glass, chemicals, paper making, metallurgy, pharmaceutical, and textile as well as food industries. It is TV dedicated reagent. It can be used for the food industry as the neutralizing agent, leavening agents such as for the manufacture of amino acids, soy sauce and pasta such as bread, bread and so on. It can also be prepared to dubbed alkaline and add into pasta to increase the flexibility and ductility. As the detergent, it can be used for wool rinse. It can also be applied to bath salts and pharmaceutical use and also be used as the alkali agent of tanning. Sodium carbonate is most used in industry with a small part using by the civilian. In the soda ash of industry purpose, it is mainly applied to light industry, building materials and chemical industry, accounting for about 2/3: followed by metallurgy, textiles, petroleum, defense, and pharmaceutical. The glass industry is the largest soda consumer sector with each ton of glass consuming 0.2 ton of soda ash. In the chemical industry, it can be used for manufacturing of sodium silicate, sodium dichromate, sodium nitrate, sodium fluoride, baking soda, borax, and trisodium phosphate. In the metallurgical industry, it is mainly used for fluxing agent, mineral flotation agent, and desulfurization agent for steel and antimony. It can also be used as water softener in printing and dyeing industry. In tanning industry, it can be used for the degreasing of raw hides, neutralizing chrome tanned leather and improving the alkalinity of the chrome liquid. It is also used in the production of synthetic detergent additive sodium tripolyphosphate and other sodium salt. It can be used as a buffer, neutralizing agent and dough conditioner. It can be used in cakes and pastas. Make appropriate use it according to actual requirement of production. It is mainly applied to float glass, funnels, optical glass. It can also be used in other sectors of chemical industry and metallurgy industry. It can reduce the flying the alkali dust through application of heavy soda ash, and thus reducing the material consumption, improving the working conditions as well as improving product quality while reducing its erosion on the refractory material to extend the life of the furnace. It is a kind of basic chemical raw material which is widely used in medicine, paper making, metallurgy, glass, textiles, dyes and other industries and can be used as a leavening agent in food industry. It can be used as analytical reagents, dehydrating agent, and battery additives.
Sodium carbonate is a white, crystalline and hygroscopic powder with a purity of > 98 %. There are two forms of sodium carbonate available, light soda and dense soda. Impurities of sodium carbonate may include water (< 1.5 %), sodium chloride (< 0.5 %), sulphate (< 0.1 %), calcium (< 0.1 %), magnesium (< 0.1 %) and iron (< 0.004 %). The purity and the impurity profile depends on the composition of the raw materials, the production process and the intended use of the product. For example the purity of the pharmaceutical grade must be higher than 99.5 % in Europe.Sodium carbonate is a strong alkaline compound with a pH of 11.6 for a 0.1M aqueous solution (The Merck Index, 1983; Johnson and Swanson, 1987). The pKa of CO3 2- is 10.33, which means that at a pH of 10.33 both carbonate and bicarbonate are present in equal amounts.