Calcium chloride (CaCl2) is a simple chemical compound of calcium and chlorine. It is extremely deliquescent (has an affinity for water) and highly soluble. Every year millions of tons of it are produced worldwide and its bulk price gravitates around $130/ton ($182 in the USA). It is delivered commercially in small white pellets or as a white dust.
Calcium chloride is produced in a liquid state as a by-product of the Solvay process used for the manufacture of sodium carbonate.
CaCO3(s) + 2 HCl → CaCl2(aq) + H2O(l) + CO2(g)
Calcium chloride has quite a few uses.
First, it is used as an antifreezing agent for ice and snow removal nearly everywhere - roads, highways, parking lots, golf links, sideways and so on. This is because the dissolving process is highly exothermic (releases heat) and rapidly produces temperatures of around 60°C (140°F). Unlike the more-common rock salt (sodium chloride) the white pellets of the calcium chloride are relatively harmless to plants and soil. It is also more effective at lower temperatures than regular salt.
It is also used in construction as an accelerator of concrete setting, maintains unpaved roads and fortifies road bases for new construction.
Calcium Chloride maintains workability in concrete with reduced water usage. In addition, faster setting means that manpower and labor hours can be reduced. And the number of forms required for a project can be minimized, since they can be re-used faster at the job-site.
It is once again calcium chloride's ability to regulate moisture on road surfaces that is the key to building roads that last. Uniform compaction and residual calcium chloride helps protect road bases from winter freezing and related frost damage. This is also due to the exothermic reaction of the compound with water and the properties of the sollution (has a freezing point of -51°C)
Calcium Chloride protection of unpaved roads and road bases is cumulative and long-lasting. The migration of calcium Chloride from road bases is minimal. Studies have shown that calcium chloride is still present and providing stabilization in road sub-bases nearly 30 years after initial construction.
Calcium Chloride is often used in mines and on roads for prevention and removal of all sort of dust as its hygroscopic nature keeps a liquid layer on the surface of the roadway or at certain places in mines, which hold the dust down.
Some of the other uses include:
1. As a drying agent in pertrochemical industry
2. As a coagulant in the rubber indurstry
3. As an additive in paper industry, and de-inking of waste paper
4. As an ingredient in some foods, especially picles, to give a salty taste while not increasing the food's sodium content.
5. Аs a drainage aid for wastewater treatment.
6. As an additive in fire extinguishers
7. As a chloridizing agent in all water treatment - swimming pools, tap water etc.
8. As an antiseptic for wheat, vegetables, fruits, etc.
Calcium Chloride is an irritant! Rubber gloves and goggles should be worn, and care must be taken to avoid inhalation. The potential health hazards are as follows:
Inhalation:
Granular material does not pose a significant inhalation hazard, but inhalation of dust may cause irritation to the respiratory tract, with symptoms of coughing and shortness of breath.
Ingestion:
Low toxicity material but ingestion may cause serious irritation of the mucous membrane due to heat of hydrolysis. Large amounts can cause gastrointestinal upset, vomiting, abdominal pain.
Skin Contact:
Solid may cause mild irritation on dry skin; strong solutions or solid in contact with moist skin may cause severe irritation, even burns.
Eye Contact:
Hazard may be either mechanical abrasion or, more serious, burns from heat of hydrolysis and chloride irritation.
Chronic Exposure:
No information found.
First Aid Measures include removing irritant in case of inhalation, water flushing in case of skin or eye contact, and inducing vomiting in case of ingestion. Calcium Chloride's Health Rating according to SAF-T-DATA(tm) is 1 (slight hazard).
Tags: science, calcium chloride dust, uses, formulas, dust, liquid
