Page 185 - Chemical and process design handbook

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CALCIUM CHLORIDE

Calcium chloride is obtained from natural brine that typically contains
14% sodium chloride (NaCl), 9% calcium chloride (CaCl ), and 3% mag-
2
nesium chloride (MgCl ). Evaporation precipitates sodium chloride, and
2
magnesium chloride is removed by adding slaked lime to precipitate mag-
nesium hydroxide.
MgCl + Ca(OH) → Mg(OH) + CaCl
2 2 2 2
Calcium chloride is used on roads for dust control in the summer and
deicing in the winter, since it is less corrosive to concrete than is sodium
chloride. Other applications of calcium chloride include thawing coal, as a
component of oil and gas well fluids, and as antifreeze for concrete.

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