Photo-Catalysis

Photo-Catalysis

 

VOC oxidation & air sterilisation with the power of UV light !

 

 

 

Content

1. Oxidation Process description

2. Process description

3. Applications

4. Advantages

5. Dimensioning

 

 

 

1. Photo-Catalysis: Oxidation Process description

Photo-Catalysis consists in degrading organic contaminants on TiO2 coated surface activated with photons produced by short UV waves (UV-C) at room temperature. Once activated, the TiO2 coated surface contains electron-hole-pairs. Once an oxygen and a carbon containing molecule adsorb on such an electron-hole-pair, they become chemi-adsorbed on the surface and activated. In such an unstable state, the 2 activated and side-by-side molecules can only react with each other and water and CO2 molecules desorb from the surface.

 

2. Photo-Catalysis: Process description

 

In a photo-catalytic system, the lamps are mounted horizontally in a honeycomb structure coated with TiO2.

 

Thanks to the use of UV-C lamps, beside the photo-catalysis oxidation process, the photo-oxidation process also occurs, which means that the entering molecules are also photolysed and a part of the oxygen is transformed in highly reactive oxygen radicals en ozone .

 

 

The combination of the photo-oxidation and photo-catalysis processes allows the system to be very compact. Consequently, this system has been called Phoenix Compact”.

 

As for the photo-oxidation process, a catalyst module, situated after the photo-catalysis module, helps to complete the oxidation process and to convert the un-reacted ozone and oxygen radicals in O2.

 

3. Applications

  • Abatement of small organic molecules, like formaldehyde, acetaldehyde, methanol, formate, methylmercaptan… which weakly adsorb on the catalyst of a photo-oxidation process; they all require a short reaction sequence to be fully oxidized.
  • Final oxidation step of a standard photo-oxidation system

4. Advantages

  • Degradation at room temperature
  • Low investment (carbon steel), energy (lamp, fan) and maintenance costs
  • Long equipment life time
  • Compact, modular and silent system; indoor and outdoor location possible
  • No start-up time; no fluid supply and waste production

5. Dimensioning

  • Each duct has a section of 1m x 1m and a maximum flow capacity of 8000 m3/h
  • For higher flow, the number of ducts = flow/8000
  • For flows smaller than 3000m3/h, a section of 700 x 700mm is preferred