Photocatalytic degradation of phenol using immobilized TiO2 in a specialized column reactor

Photocatalysis advanced oxidation process (AOP) was used to study degradation of phenol with use of titanium dioxide nano-particles (as a photocatalyst) coated on stainless steel sieve plates. Titanium dioxide (TiO2 Degussa P-25) was immobilized by a very simple and inexpensive method. Characteristics of prepared catalyst (TiO2 immobilized on sieve plate) including anatase-rutile phase ratio and crystal size of TiO2, morphology of catalyst surface and specific surface area, was inspected by XRD, SEM and BET analyses respectively. The XRD results did not reveal any significant change in the structure of TiO2 crystals as a consequence of the applied catalyst immobilization method and wastewater treatment processes. Well and uniform coating of TiO2 nano-particles on support was confirmed by SEM images. Also BET test, SEM images and weighting showed negligible wash out of TiO2 after all of treatment experiments (about 200 hours). Photocatalytic treatment experiments of synthetic wastewater containing phenol, was SHUIRUPHGLQDQ³$QQXODr Sieve-Plate Column 3KRWRUHDFWRU´ZKHUHWKHULQJVRIprepared catalyst was installed in the annulus through (which the synthetic wastewater flowed), and exposed to UV irradiation by a 15 Watt UV-Lamp situated properly inside the inner quartz tube. Phenol concentration and COD was measured every 1 hour during all of the treatment experiments to monitor the degradation rate of initial pollutant and overall pollution load (considering intermediate products) respectively. Efficiency of defined photoreactor using batch recirculation flow (7 hours) was determined in terms of phenol removal and decreasing COD level (%). The initial concentration of phenol was set at two levels, 0.5 and 1.0 (mM) and results were as follows: The Efficiency for phenol removal was 99.71% and 80.66% while the efficiency for decreasing COD level was 90.68% and 45.24% respectively.

Keywords:

Annular Sieve-Plate Column Photoreactor , Immobilized TiO2 , Phenol , Photocatalytic Degradation , Stainless Steel