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 appears as white, hard fragments or particles at room temperature. Its common applications include saltwater used in refrigeration equipment, road deicing agents, and desiccants.
Calcium chloride is a colorless cubic crystal, white or grayish white, in the form of granules, honeycomb blocks, spheres, irregular granules, and powders. Slightly toxic, odorless, and slightly bitter in taste. Exposed to the air, it is highly susceptible to deliquescence. It is easily soluble in water and has a solubility of 74.5 g/100g of water at 20 ℃. At the same time, it releases a large amount of heat (the dissolution enthalpy of calcium chloride is -176.2 cal/g), and its aqueous solution is neutral. Easy to dissolve in various polar and protonic solvents, solubility in the following solvents (g/100mL solvent) at 20 ℃: methanol: 29.2, anhydrous ethanol: 25.8, n-propanol: 15.8, n-butanol: 25.0, n-pentanol: 11.5, ethylene glycol: 21.6 (25 ℃), formic acid: 43.1, acetic acid: 15.0 (30 ℃), hydrazine: 16.0. But in dipole solvents and low polarity solvents, such as ether, tetrahydrofuran, etc., they are only slightly soluble or insoluble. React with ammonia or ethanol to generate CaCl2 · 8NH3 and CaCl2 · 4C2H5OH complexes, respectively. At low temperatures, the solution crystallizes and precipitates hexahydrate. When gradually heated to 30 ℃, it dissolves in its own crystalline water and gradually loses water. When further heated to 200 ℃, it becomes dihydrate. When further heated to 260 ℃, it becomes white porous anhydrous calcium chloride. During the heating and dehydration process of hydrated calcium chloride, some parts undergo hydrolysis reactions, resulting in the presence of 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 for 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 fireproof agent. Used as a protective 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 freezing; Desiccant; Anti caking agents; Microbial suppressants; Pickling agent; Organizational improvement agents.
3. Used as a desiccant, road dust collector, defogger, fabric fireproof agent, food preservative, and in the production of calcium salts.
4. Used as a lubricant additive.
5. Used as an analytical reagent.
6. Mainly used to treat tetany, urticaria, exudative edema, intestinal and ureteral colic, magnesium poisoning caused by decreased blood calcium.
7. Used as a calcium fortifier, solidifying agent, chelating agent, and drying agent in the food industry.
8. Can increase the permeability of bacterial cell walls.
Food use:
As a food ingredient, calcium chloride can act as a multivalent chelating agent and solidifying agent. It has been approved by the European Union for use as a food additive, with the E code E509. Generally recognized as safe (GRAS) by the US Food and Drug Administration. It is estimated that each person consumes 160 to 345 milligrams of calcium chloride food additives per day.
Calcium chloride can be used as a curing agent in canned vegetables. It can also solidify soy curd to form tofu, and serve as a raw material for cooking molecular foods by reacting with sodium alginate to gelatinize the surface of vegetables and fruit juices to form small balls similar to caviar. Add as an electrolyte to sports drinks or some soft drinks, including bottled water. Due to its strong salty taste, calcium chloride can be used as a substitute for salt in the production of pickled cucumbers without increasing the sodium content of food. Calcium chloride can lower the freezing point property and is used to delay the freezing of caramel in chocolate bars filled with caramel.
Calcium chloride is added to beer brewing solutions that lack minerals, as calcium ions are one of the most influential minerals in the beer brewing process. They affect the acidity of malt juice and have an impact on yeast activity. And calcium chloride can bring sweetness to the brewed beer.
Other aspects: Hydrated calcium chloride solid can be used as a phase change energy storage material. For example, hexahydrate calcium chloride can be used for industrial waste heat recovery and solar radiation heat absorption at medium and low temperatures due to its melting point of 30 ℃ and melting heat (i.e. the heat absorbed during the transformation of substances from solid to liquid at the same temperature) reaching 190 kJ/mol. However, it is similar to all inorganic hydrate salt phase change materials and has a serious problem of undercooling (its undercooling reaches 20 ° C), which requires the addition of nucleating agents to overcome.
Calcium chloride plays a role in accelerating the initial setting in concrete, but chloride ions can cause corrosion of steel bars, so calcium chloride cannot be used in reinforced concrete. Anhydrous calcium chloride can provide a certain amount of moisture to concrete due to its hygroscopicity.
Calcium chloride is also an additive in plastics and fire extinguishers. It serves as a filter aid in wastewater treatment and as an additive in blast furnaces to control the aggregation and adhesion of raw materials, thereby avoiding furnace material settling. It also acts as a diluent in fabric softeners.
The exothermic nature of calcium chloride dissolution makes it suitable for use in self heating cans and heating pads.
In the petroleum industry, calcium chloride is used to increase the density of solid-free saltwater, and can also be added to the aqueous phase of emulsified drilling fluid to suppress the expansion of clay. As a flux, it plays a role in reducing the melting point in the production of metallic sodium by the David method of electrolytic melting of sodium chloride. When making ceramics, calcium chloride is used as one of the material components, which suspends clay particles in the solution, making it easier to use clay particles during grouting.
matters needing attention：
If dust is accidentally inhaled, ingestion can be harmful to health. Dust can burn, irritate the nasal cavity, mouth, and throat, and can also cause nosebleeds and damage nasal tissue; Dry powder can irritate the skin, while the solution can severely irritate or even burn the skin.
After skin contact, remove contaminated clothing and rinse with plenty of flowing water.
If the eyes come into contact and lift the eyelids, rinse with flowing water or physiological saline and seek medical attention.
If accidentally inhaled or ingested: Remove from the scene to a place with fresh air. If breathing is difficult, administer oxygen and seek medical attention. Drink plenty of warm water to induce vomiting. Seek medical attention.
Emergency response：
Isolate the contaminated area and restrict entry and exit. Avoid dust, sweep carefully, place in a bag and transfer to a safe place or transport to a waste disposal site for disposal.
Operation precautions：
Close operation and strengthen ventilation. Operators must undergo specialized training and strictly adhere to operating procedures. It is recommended that operators wear self-priming filter type dust masks to avoid generating dust. When handling, it is important to load and unload with care to prevent damage to the packaging and containers.
Storage precautions：
Store in a cool and ventilated warehouse. The packaging container must be sealed to prevent moisture. Separate from deliquescent items.