Chlorine is a naturally occurring substance. Hypochlorite is a chemical compound containing chlorine in an oxidated state, meaning that it has lost electrons. The two most common forms are sodium hypochlorite and calcium hypochlorite.
The production of hypochlorite dates back to 1789. It was produced when chlorine gases passed through a sodium carbonate solution. The resulting sodium hypochlorite was called Javel water, named after the place in France where the procedure was done. This is a liquid chemical compound normally used for cleaning and purification, and in a solution, it is commonly known as chlorine bleach. Some water purifiers and cleaning supplies also contain the substance.
The first hypochlorite production method was not as efficient as current methods, and the solution was considerably weaker. After Javel water was produced, people continued seeking better ways of making it. Doing so resulted in a process that involved extracting chlorinated lime, known as calcium hypochlorite or bleaching powder.
Chlorinated lime is usually a white or grayish-white powder, but it is also available as tablets. It is a strong oxidizer and is considered more stable than sodium hypochlorite. It is also believed to provide more chlorine.
One of its most popular uses is to make swimming pools and hot tubs hygienic. It can also be used to purify drinking water. In industrial settings, it is often used to clean bed sheets and other cloth materials.
Choosing whether to use sodium or calcium hypochlorite as a purifier normally depends on the amount of water being used. The calcium compound is usually reserved for jobs that involve less than five million gallons of water per day. This includes small water systems, such as those that are installed in developing countries. The type of water may also be taken into account. The sodium compound is typically preferable for hard water.
Although the use of sodium and calcium hypochlorite are common in both household and industrial settings, these chemical compounds can be dangerous. They can be health hazards if swallowed, although in most cases they are not fatal if only a small amount is ingested. If these compounds are ingested, experts usually recommend the person drink water or milk. Only minor stomach irritation should result, which will eventually subside.
These chemicals can also be dangerous if they are inhaled. The risk posed by inhalation increases when the substances are mixed with ammonia. When combined, chlorine and ammonia can produce a toxic gas that results in serious breathing problems. Calcium hypochlorite is corrosive, and appropriate measures should be taken to ensure that the powder is not inhaled into the lungs.
Hypochlorite compounds are usually regarded as unstable. The calcium compound, however, is regarded as more stable than its sodium counterpart. Both tend to decompose in sunlight, but special measures are often taken to counteract this reaction in chemicals that will be exposed to the sun, such as swimming pool sanitizers.