Calcium chloride is a chemical substance composed of chlorine and calcium elements, with the chemical formula CaCl2, slightly bitter. It is a typical ionic halide, which is white, hard fragments or particles at room temperature. Its common applications include saline water used in refrigeration equipment, road ice melting agents, and desiccants.
Colorless cubic crystal, white or grayish white, in the form of granules, honeycomb blocks, spheres, irregular granules, or powders. Slightly toxic, odorless, and slightly bitter in taste. Extremely hygroscopic and prone to deliquescence when exposed to air. It is easily soluble in water and has a solubility of 74.5 g/100g of water at 20 ºC. At the same time, it emits a large amount of heat (the dissolution enthalpy of calcium chloride is -176.2 cal/g), and its aqueous solution is neutral. Easily soluble in various polar and proton solvents, with solubility in the following solvents (g/100mL solvent) at 20 ºC: methanol: 29.2, anhydrous ethanol: 25.8, n-propanol: 15.8, n-butanol: 25.0, n-pentanol: 11.5, ethylene glycol: 21.6 (25 ºC), formic acid: 43.1, acetic acid: 15.0 (30 ºC), hydrazine: 16.0. However, in dipole solvents and low polarity solvents, such as ether and tetrahydrofuran, they are only slightly soluble or difficult to dissolve. React with ammonia or ethanol to generate CaCl2 · 8NH3 and CaCl2 · 4C2H5OH complexes, respectively. The solution crystallizes at low temperature and precipitates hexahydrate. When it is gradually heated to 30 ºC, it will dissolve in its own crystal water. After continuous heating, it will gradually lose water. When it is heated to 200 ºC, it will become dihydrate. When it is heated to 260 ºC, it will become white porous anhydrous calcium chloride. During the heating and dehydration process of hydrated calcium chloride, some parts undergo hydrolysis reactions, resulting in small amounts of CaO impurities in the product.
Industrial use
1. Used as a versatile desiccant, such as for drying gases such as nitrogen, oxygen, hydrogen, hydrogen chloride, sulfur dioxide, etc. Used as a dehydrating agent in the production of alcohols, esters, ethers, and acrylic resins. Calcium chloride aqueous solution is an important refrigerant used in refrigerators and ice making, which can accelerate the hardening of concrete and increase the cold resistance of building mortar. It is an excellent building antifreeze. Used as a port defogger, road dust collector, and fabric fire retardant. Used as a protective agent and refining agent for aluminum magnesium metallurgy. It is a precipitant for producing lake pigments. Used for deinking waste paper processing. It is the raw material for producing calcium salts.
2. Chelating agent; Curing agent; Calcium fortifier; Refrigerant for refrigeration; desiccant; Anticoagulant; Microbial suppressants; Pickling agent; Organizational improvers.
3. Used as a desiccant, road dust collector, defogger, fabric fire retardant, food preservative, and in the manufacture of calcium salts.
4. Used as a lubricant additive.
5. Used as an analytical reagent.
6. Mainly used for treating tetany, urticaria, exudative edema, intestinal and ureteral colic, magnesium poisoning, etc. caused by decreased blood calcium.
7. Used as a calcium fortifier, solidifying agent, chelating agent, and desiccant in the food industry.
8. Can increase the permeability of bacterial cell walls