Wet peroxide oxidation process catalyzed by Cu/Al 2 O 3 : phenol degradation and Cu 2+ dissolution behavior.

Catalytic wet peroxide oxidation (CWPO) has become an important deep oxidation technology for organics removal in wastewater treatments. Supported Cu-based catalysts belong to an important type of CWPO catalyst. In this paper, two Cu catalysts, namely, Cu/Al 2 O 3 -air and Cu/Al 2 O 3 -H 2 were prepared and evaluated through catalytic degradation of phenol. It was found that Cu/Al 2 O 3 -H 2 had an excellent catalytic performance (TOC removal rate reaching 96%) and less metal dissolution than the Cu/Al 2 O 3 -air case. Moreover, when the organic removal rate was promoted at a higher temperature, the metal dissolution amounts was decreased. Combined with hydroxyl radical quenching experiments, a catalytic oxidation mechanism was proposed to explain the above-mentioned interesting behaviors of the Cu/Al 2 O 3 -H 2 catalyst for CWPO. The catalytic test results as well as the proposed mechanism can provide better guide for design and synthesis of good CWPO catalysts.