Ozone is a very active form of oxygen. It is formed when oxygen is exposed to a high-energy field causing some oxygen molecules (O2) to break down to oxygen atoms (O). The oxygen atoms (O) then react with the oxygen molecules (O2) to form ozone (O3). Notice that this is a reversible reaction meaning that ozone can decompose back to oxygen.
Is ozone found in nature ?
Yes, ozone is formed by lightning.
In nature, ozone is produced by the action of lightning on the oxygen found in the air. The formation of ozone leads to the fresh smell that you find outside after a lightning storm. One type of ozone generator, known as the corona discharge type, mimics this natural process in its ozone generating cells.
Yes, ozone is found in the Earth's stratosphere.
Also, the ozone layer found in the upper stratosphere protects the earth's surface from harmful UV rays. UV rays cleave oxygen molecules into oxygen atoms which recombine to form ozone. UV rays also excite ozone molecules causing them to breakdown to oxygen to begin the cycle again. In this way, the energy of the UV rays is absorbed by the "ozone layer" protecting the Earth's surface from their harmful effects. UV-type ozone generators mimic this natural process.
What can ozone be used for ?
The very reactive nature of ozone makes it the ideal oxidant for air and water treatment. Ozone will:
- destroy bacteria and viruses
- precipitate heavy metals (example iron and manganese) allowing them to be filtered
- eliminate colour from water (for example, like the yellowish colour caused by tannin)
- remove rotten egg smell from water (caused by hydrogen sulfide)
- oxidise organic compounds to form compounds that can be easily flocculated and filtered or to form water (H2O) and carbon dioxide (CO2).
- eliminate bad odours from air
Applications include pool & spa treatment , home drinking water treatment, irrigation water treatment, smoke odour elimination from air, seafood storage… the list goes on and on.
The collage below shows but a few areas where ozone has been used successfully to improve water and air quality and to improve industrial processes.
What happens to unreacted ozone ?
Unreacted ozone converts back to oxygen - leaving behind no harmful by-products!