Removal of color compounds from recycled water using combined activated carbon adsorption and AOP decomposition

In this study, a hybrid adsorbent (TiO₂/AC) with photocatalytic ability was prepared by coating TiO₂ nanoparticles on the surface of activated carbon granules, and was used to remove color and trace organic compounds remained in the actual treated effluent. The adsorbed organic compounds were then decomposed using advanced oxidation processes (AOPs) including UV/TiO₂ and UV/TiO₂/H₂O₂, and the used adsorbent were regenerated for reuse. The effects of UV irradiation time and H₂O₂ concentration on the efficiency of regeneration were investigated. The data obtained in this study demonstrated that TiO₂/AC could efficiently (around 90%) remove color and A ₂₅₄ (the organics absorption at the wavelength of 254 nm) from the actual treated effluent within 1 h of adsorption treatment. The photocatalytic process (UV/TiO₂) was effective for the regeneration of used TiO ₂/AC, and this regeneration process could be significantly enhanced with the assistance of H₂O₂.