Removal of 2,4‐dichlorophenol by aluminium/ O 2 /acid system

Background Although the oxidative removal of organic compounds by the Al/ O 2 /acid system has been previously studied, the in situ generation of reactive oxygen species ( ROS ) and its influencing factors are not well understood. 2,4‐dichlorophenol (2,4‐ DCP ) is one of the priority control pollutants and widely present in the environment. In this study, the oxidative removal of 2,4‐ DCP by the Al/ O 2 /acid system was investigated, especially the in situ generation of ROS and influencing factors . Results More than 90% of 2,4‐ DCP was removed within 10 h in pH 2.5 solutions initially containing 10 g L −1 Al and 8.25 mg L −1 dissolved oxygen. The removal of 2,4‐ DCP was acid and oxygen driven and was accompanied by the release of chloride ions. While the reduction of oxygen to H 2 O 2 by Al was obtained only under conditions of pH < 4.0, the subsequent Al‐mediated transformation of H 2 O 2 to • OH was achieved under pH < 5.0 conditions. Furthermore, five primary intermediates were identified and oxidation pathways of 2,4‐ DCP by the Al/ O 2 /acid system were proposed . Conclusions This work describes a potential method for the removal of 2,4‐ DCP in aqueous environments. Oxygen levels and solution pH played important roles in the removal of 2,4‐ DCP by Al/ O 2 /acid system. © 2013 Society of Chemical Industry