Lime, as the most affordable basic material available on the market, is used: in the chemical industry for the production of combinations between organic and inorganic calcium; as adjuvant of the reaction in chemical syntheses; to alter the pH; in chemical decompositions or physical-chemical preparation processes. In the latter case, lime causes the sedimentation of many impurities and reaction products in a colloidal solution that forms insoluble combinations with Ca++ or OH-ions. In most cases, micronized calcium oxide or highly pure calcium hydroxide is used in the chemical industry for the following main purposes:
INORGANIC CHEMISTRY
- Production of calcium carbide and calcium cyanamide;
- Production of soda and potash;
- Production of calcium precipitate and calcium salts;
- Production of glass.
ORGANIC CHEMISTRY
- Production of ethylene and propylene oxides;
- Production of glycerine and polyvalent organic acids;
- Production of leather, food products and sugar.
In leather industry, lime is requested in form of calcium hydrate suspension for depilation, and for the calcination of leathers. In food industry, lime is used in the churning of milk to decrease its acidity, in the processing of residues from citrus fruits and grape, and in preserving apples and pre-packaged foods. In the industrial extraction of raw sugar, lime is an essential element, regardless if the starting base is cane or beetroot. From the juice obtained through squeezing or diffusion, lime separates the sugar content from unwanted concomitant substances.