(769c) Efficiency Factors In Photocatalytic Reactors for Air Treatment

Authors: 
Garcia Hernandez, J. M., University of Western Ontario
de Lasa, H. I., University of Western Ontario


Efficiency Factors are key parameters for assessing photocatalytic degradation efficiency and photocatalytic reaction pathways in air treatment units. While the PTEF (Photochemical Thermodynamic Efficiency Factor) and QY (Quantum Yield) has been considered for photocatalytic conversion of organic pollutants in water (1), definition of efficiency factors in air treatment reactors is a new initiative of CREC researchers. Efficiency calculations are performed in the present study, using data for acetone and acetaldehyde photocatalytic degradation in air with low concentration of water. Efficiency factors are established in two Photo-CREC-Air reactor scales of 14.7 liters and 60 liters capacity (2,3,4). On the basis of the number of OH consumed, the enthalpy of OH formation and the radiation absorbed in the mesh supported photocatalyst, it is shown that quantum yields both for acetone and acetaldehyde supersede in cases the value of 1 (equivalent to 100%) while PTEFs remaining below the level of 1 as required by thermodynamic constrains. On this basis, a chain reaction mechanism can be supported for photocatalytic conversion of organic pollutants in air.

  1. Serrano B., Ortiz A., Moreira J., de Lasa H., “Photocatalytic Thermodynamic Efficiency Factors (PTEF). Practical Limits in Photocatalytic Reactors” Vol. 9, N5, 6824-6832 Ind.Eng.Chem.Res. (2010).
  2. Ibrahim H., de Lasa H., “Kinetic Modeling of the Photocatalytic Degradation of Air Borne Pollutants”, AIChE J., Vol.50, 1017-1027  (2004).
  3. Romero-Vargas S., Ibrahim H., de Lasa H.“ Flow Field Investigation in a Photocatalytic Reactor for Air Treatment (Photo-CREC-air).  Chem,.Eng.Sci. Vol. 61, 3343-3361 (2006)
  4. Garcia Hernandez J, Serrano B., de Lasa H.,”The Photocatalytic Energy Efficiency Factors (PTEF) in Photocatalytic Reactors for Air Treatment” Chem.Eng.J. Vol.165, 891-901 (2010).