Abstract:
In this study, advanced photochemical oxidation processes, UV/H2O2 and photo-Fenton systems were investigated for phenol
degradation in wastewater with low-pressure mercury vapor lamp. The results indicated that in the UV/H2O2 system, a sufficient
amount of H2O2 was necessary, but a very high H2O2 concentration inhibited the photolysis rate. The optimum H2O2
concentration was achieved in the range of 0.05-0.1 mol/L at phenol concentration of 100 mg/L. No pH effects were observed in
the range of 4-10. The results of study showed that the UV/H2O2/Fe(II) system was the most effective treatment process under
acidic condition and generated a higher rate of phenol degradation at a very short time. It enhanced the oxidation rate by 3 times
the rate for the UV/H2O2 process. For all these reactions, the degradation rates are evaluated by determining their first-order rate
constants and half-life times. At the optimum condition, phenol completely disappeared with UV/H2O2 and UV/H2O2/Fe(II)
systems in less than 50 min and 20 min, respectively.

Ali Assadi, Akbar Eslami