About Ozone

What is ozone?

Ozone (O3), sometimes called “activated oxygen”, contains three atoms of oxygen rather than the two atoms we normally breathe. Ozone is the second most powerful oxidant in the world and can be used to destroy bacteria, viruses, and odors.

How does ozone work?

The third oxygen atom of ozone makes it extremely reactive. This atom readily attaches itself to other molecules and changes the oxidation state of those molecules, therefore creating oxidation. When contaminants such as odors, bacteria, or viruses make contact with ozone, their chemical structure changes state.  This process is called oxidation. Ozone essentially reverts back to oxygen after it is used. This makes it a very environmentally friendly oxidant.

How is ozone produced?

There are basically two methods of producing ozone…ultra-violet and corona discharge. Corona discharge creates ozone by applying high voltage to a metallic grid sandwiched between two dielectrics. The high voltage passes through the dielectric to a grounded screen/plate and in the process, creates ozone from oxygen present in the chamber. Ultra-violet (UV) light creates ozone when a wavelength at 254 nm (nanometers) hits an oxygen atom. Both processes split oxygen molecules into single oxygen atoms (O). These atoms combine with another oxygen molecule (O2) to form ozone (O3).

Ozone Properties

Ozone is one of the most powerful oxidants used in water and air applications. See the different properties of ozone below:

Property Ozone Oxygen
Molecular Weight 48 32
Color light blue colorless
Smell smell after lightning storms odorless
Solubility in Water (0-deg C) 0.64 0.049
Density (g/l) 2.144 1.429
Electrochemical Potential (Volts) 2.07 1.23

Typical O3 half-life vs. Temperature

Temperature (C) Half-Life*
-50 3 months
-35 18 days
-25 8 days
20 3 days
120 1.5 hours
250 1.5 seconds
Dissolved In Water
Temperature (C) Half-Life
15 30 minutes
20 20 minutes
25 15 minutes
30 12 minutes
35 8 minutes

* These values are based on thermal decomposition only. No wall effects, humidity, organic loading or other catalytic effects are considered.

Ozone Solubility

The solubility of ozone depends on the water temperature and the ozone concentration in the gas phase.  As the concentration of ozone increases and the temperature of the water decreases the solubility of ozone into water increases.  See chart below:

ozone solubility


Learn more about ozone HERE