Removal of phenol from contaminated kaolin using electrokinetically enhanced in situ chemical oxidation

The application of electrokinetic treatment to phenol contaminated soil combined with the addition of a chemical oxidant (permanganate) to the catholyte has been evaluated. It was found that the counter-current flow of the phenol (by electrosmosis) and permanganate (by electromigration) leads to a rapid oxidation of the phenol in the soil. After 5 days of treatment over 90% of the phenol (initial concentration 1 g kg(-1) dry soil) in a 15 cm long container of kaolin was removed by electrokinetic treatment with a voltage gradient of 1 V cm(-1) and an initial concentration of KMnO4 of 9 g L(-1) in the catholyte. This level of treatment was achieved with an electrical energy consumption of less than 15 kWh per m3 of soil treated.