Liquid calcium chloride

Characteristics of liquid calcium chloride:

Liquid calcium chloride has the characteristics of conductivity, lower freezing point than water, heat dissipation when in contact with water, and good adsorption function. Its low freezing point can be used in various industrial manufacturing and public places.

The function of liquid calcium chloride:

1. Alkaline: Calcium ions hydrolyze to an alkaline state, while hydrogen chloride easily evaporates after chloride ion hydrolysis.

2. Conductivity: There are ions in the solution that can move freely.

3. Freezing point: The freezing point of calcium chloride aqueous solution is lower than that of water.

4. Boiling point: The boiling point of calcium chloride aqueous solution is higher than that of water.

5. Evaporation crystallization: Calcium chloride aqueous solution should be evaporated and crystallized in an atmosphere filled with hydrogen chloride.

De icing agent and cooling bath

Calcium chloride can lower the freezing point of water, and spreading calcium chloride hydrate on roads can prevent freezing and de icing and snow melting. However, the salt water generated by the melting of ice and snow can damage the soil and vegetation along the road and deteriorate the concrete on the road surface.

Calcium chloride solution can also be mixed with dry ice to prepare a low-temperature cooling bath. Add rod-shaped dry ice in batches to the saline solution until ice cubes appear in the system. The stable temperature of the cooling bath that can be maintained by different types and concentrations of salt solutions may vary. Calcium chloride is commonly used as a salt raw material, and the required stable temperature is obtained by adjusting the concentration. This is not only because calcium chloride is cheap and easy to obtain, but also because the eutectic temperature of calcium chloride solution (i.e. the temperature at which the solution solidifies into granular ice salt particles) is quite low, reaching -51.0 ℃. This allows for an adjustable temperature range from 0 ℃ to -51 ℃. This method can be implemented in Dewar flasks that can provide insulation, or in general plastic containers used to hold cooling baths when the volume of the Dewar flask is limited and a large amount of salt solution needs to be prepared. In this case, the temperature maintenance is also relatively stable.

As a source of calcium ions

Adding calcium chloride to swimming pool water can make it a pH buffering solution and increase its hardness, which can reduce the erosion of the pool wall concrete. According to the Le Chatelier principle and the same ion effect, increasing the concentration of calcium ions in pool water will slow down the dissolution of essential calcium compounds in concrete structures.

Adding calcium chloride to the water of marine aquariums can increase the amount of available calcium for aquatic organisms. Molluscs and coelacanths raised in aquariums use it to form a shell of calcium carbonate. Although using calcium hydroxide or a calcium reactor can achieve the same goal, adding calcium chloride is the fastest method and has the least impact on the pH value of water.

Other uses of calcium chloride

The exothermic nature of calcium chloride dissolution makes it suitable for use in self heating cans and heating pads.

Calcium chloride plays a role in accelerating the initial setting of concrete, but chloride ions can cause corrosion of steel bars, so calcium chloride cannot be used for reinforced concrete. Anhydrous calcium chloride can provide a certain degree of moisture to concrete due to its hygroscopicity.

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 fluids to suppress clay expansion. As a fluxing agent, it plays a role in lowering the melting point during the production of metallic sodium by electrolysis of molten sodium chloride in the Davy process. 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.

Calcium chloride is also an additive in plastics and fire extinguishers. It is used as a filter aid in wastewater treatment, as an additive in blast furnaces to control the aggregation and adhesion of raw materials to avoid settling of furnace materials, and as a diluent in fabric softeners.