New Insights into the Mechanism of the Catalytic Decomposition of Hydrogen Peroxide by Activated Carbon: Implications for Degradation of Diethyl Phthalate

This study investigated the catalytic decomposition of H 2 O 2 by activated carbon (AC) and its implications for degradation of diethyl phthalate (DEP). It was found that AC exhibited excellent catalytic ability for decomposition H 2 O 2 and degradation of DEP. HNO 3 modification altered the surface characteristics of AC together with the concentrations and types of AC free radicals (FRs), which further promoted generation of • OH. Positive correlations were found between FR concentration and generation of • OH ( R 2 = 0.856) and between the proportion of surface-bound hydroxyl groups (C–OH) and the decomposition rate of H 2 O 2 ( R 2 = 0.776), indicating that FRs in AC were the main contributor to • OH generation, whereas C–OH groups were predominantly responsible for decomposition of H 2 O 2 . Electron capturing studies demonstrated that the decomposition reaction likely involves the transfer of FR electrons to H 2 O 2 to induce formation of • OH.