What is ozone?
Ozone – a term known to everyone. It is mainly associated with the “ozone hole” and the characteristic smell of air after a storm. What is it and what are its properties? What purpose is it made by humans for?
Stratospheric and tropospheric ozone – differences
Ozone, also called tritylene, is an allotropic form of oxygen consisting of triatomic molecules. It is a non-flammable, water-soluble and thermally unstable gas, which under normal conditions is characterized by a blue color and a density higher than air. At a temperature in the range of -193 – 111 C, it takes the form of a violet liquid – in this state it tends to be explosive, e.g. when in contact with trace amounts of organic matter. Ozone is formed through electric discharge or due to solar radiation – depending on the atmosphere layer. The following variations are distinguished:
• stratospheric ozone called the ozone layer – formed in the stratosphere (upper atmosphere) due to the action of solar radiation on oxygen molecules; it is very valuable from the point of view of the Earth and its inhabitants, because it provides protection against harmful ultraviolet (UV) radiation,
• tropospheric ozone (ground level) – formed at the surface of the Earth and is air pollution dangerous to living organisms.
At this point, it should be remembered that ozone is present in all layers of the atmosphere, but it accumulates only in these two mentioned above. The ozone hole mentioned in the introduction is nothing but ozone depletion – the wider it is, the larger amounts of harmful UV radiation reach the Earth’s surface. The elevated concentration of tropospheric ozone is also dangerous because it contributes to the development of diseases of the respiratory and circulatory systems -its highest concentration is recorded in the spring and summer.
Properties and application of ozone
In addition to the features discussed so far, ozone has also very strong oxidizing, toxic and aseptic properties. Due to the latter, it is considered one of the most effective disinfectants. It is about 50 times more effective than chlorine and very quickly kills viruses, bacteria, fungi and spores, although due to the relatively short time of decomposition, ozone is unable to completely replace chlorine in the water treatment process. In addition, it is widely used, among others in:
• hospitals, where it is used to sterilize rooms,
• the food industry, e.g. ozone decontamination of the top layer of fruits and vegetables prolongs their freshness and thus the shelf-life date,
• automotive industry – ozonization allows to decontaminate the interior of the car, get rid of unpleasant odors or remove bacteria, mites, pollen and nicotine from the evaporator, etc.,
• cosmetology, e.g. for the production of cosmetics based on the ozonated olive oil.