Degradation of phenol by ozone in the presence of Fenton reagent in a rotating packed bed

The degradation of phenol using ozone combined with Fenton reagent (O3/Fenton) in a rotating packed bed (RPB) was investigated in this study, and the O3/Fenton process was compared with O3 process. The phenol degradation rate in O3/Fenton process was roughly 20% higher than that in O3 process and reached 98.3% at H2O2 concentration of 1.6 mM. It was also found out that phenol degradation rate was significantly affected by the rotation speed of RPB, inlet ozone concentration and H2O2 concentration. Phenol degradation rate increased with increasing rotation speed, H2O2 concentration and inlet ozone gas concentration, and reached maximum at a temperature of 25 °C, initial pH in the range of 5–6.8 and Fe(II) concentration of 0.1 mM. The BOD/COD of the phenol solution increased from 0.2 to 0.58 after the solution was treated in O3/Fenton-RPB system at pH of 6.8. Analysis of the intermediates showed comparatively more complete phenol degradation in O3/Fenton process.