Advanced treatment of phenol by H2O2/UV/activated carbon coupling: Influence of homogeneous and heterogeneous phase

In this work, a heterogeneous catalytic wet peroxide process combining activated carbon (AC) and hydrogen peroxide (H2O2)/ultraviolet radiation was applied for the aqueous-phase removal of phenol. The influence of the pH and peroxide concentration were determined according to a factorial plan. The kinetic contribution of radical mechanisms (HO degrees) was estimated using a radical scavenger (tert-butyl alcohol). The degradation kinetics was modelled by a global pseudo-first-order kinetic model based on the sum of the effects during the treatment process. The results showed that these two variables significantly affected the percentage removal. The peroxide concentration exerted a positive effect (i.e., as the H2O2 concentration increased, the percentage removal also increased). Additionally, as the pH value increased, the degradation accelerated, and the kinetic constant (k(homogeneous)) increased from 0.00938min(-1) to 0.02772min(-1). The results obtained in the presence of AC demonstrated the ability of AC to ameliorate the degradation of phenol; for example, heterogeneous was 45.69 % to 41.35%.