Cleaner Air

A single BIOIZER^® bulb eliminates contaminants for up to 3200 cubic feet per 25 watt lamp using photocatalytic oxidation. To be effective, the bulb must be turned on and exposed to the air.  It will not destroy contaminants in an enclosed fixture.  For applications where the light is shielded by a lens or fixture, BIOIZER offers a variety of lens, lamps, parabolics and fixtures.

Sunlight is both a source of life and destruction. The sun’s powerful ultraviolet rays continually cause chemical reactions - activating powerful redox reactions in which atoms are chemically changed. These reactions have been studied for well over three decades as researchers look for ways to turn destruction into beneficial applications.

Photocatalytic oxidation (PCO) is an emerging technology where water or air is purified by the chemical action of light. Photocatalytic oxidation converts toxic compounds, even carbon monoxide and nitrous oxide, into benign constituents such as carbon dioxide, water and dilute mineral acids without wearing out or losing its effectiveness. BIOIZER technology uses photocatalytic oxidation (PCO) to eliminate a wide range of chemical and biological contaminants. Unlike adsorbents, photocatalysts chemically destroy these contaminants without producing harmful chemical residue, such as ozone.

PCO takes place when UV light (sunlight) activates a semiconductor photocatalyst in the presence of oxygen and moisture. Activation of the catalyst generates hydroxyl radicals and superoxide ions, powerful oxidizing species that attack and break down organic compounds.

BIOIZER uses one of the most popular photocatalystic materials - titanium dioxide (TiO2), which offers a combination of stability, photoactivity, low-cost, and non-toxicity. Titanium dioxide is unaffected by acids, bases, or organic solvents, and stable up to several hundred degrees.

In the photocatalytic process, the UV light can be supplied by ambient sunlight or electric lamps. For industrial applications, UV backlights or arc lamps are used; however, ordinary indoor fluorescent lighting typical produce enough UV energy to activate the catalyst.  Fluorescent lamps are ideal in indoor applications.  In outdoor applications, direct or diffuse sunlight is effective, thus the process functions on clear or cloudy days.

Photo activated reactions on a titanium dioxide particle. The TiO2 particles must be accessible at the surface of the coating for contact with the air and adsorbed contaminants.

In the illustration above, the photoactive coating is shown directly applied to the underlying substrate that is inert to oxidative attack. Glass, ceramic, some metals, and fluoropolymers can be coated in this fashion. If the underlying substrate is vulnerable to oxidation, for example, organic paint or most polymers, the substrate must be protected from the attack by the photocatalyst. BIOIZER accomplishes this with an inert underlying protective layer.

Although the efficacy of TiO2-based photocatalysis is well documented, there are several challenges for effective utilization of a transparent, photocatalytic coating:

• The photocatalyst must be exposed at the surface,
• The photocatalyst must adhere to the surface,
• The underlying substrate must be protected from attack by the photocatalyst,
• The photocatalyst coating must be optically transparent so that visible light is unaffected.

BIOIZER meets these challenges through a patent-protected process that has been extensively tested.