Removal of 2,4,6-Trichlorophenol from Spiked Clay Soils by Electrokinetic Soil Flushing Assisted with Granular Activated Carbon Permeable Reactive Barrier

Abstract

A study was performed on the removal of 2,4,6-trichlorophenol (TCP) from synthetic polluted soils using electrokinetic soil flushing (EKSF) assisted by a granular activated carbon-permeable reactive barrier (GAC-PRB). The polluted soils consist of spiked kaolin and were obtained by directly mixing kaolin with a 200 mg dm–3 TCP solution. Remediation tests were conducted at the bench-scale. The obtained results demonstrated that EKSF assisted with GAC-PRB is a very efficient technology for the removal of TCP from soils. For a given remediation period, the applied electric field is a very important parameter that influences the removal efficiency. Under optimized conditions, the one week-long remediation test obtained removals greater than 80% with energy consumptions below 200 kWh m–3. The effects of the electric field on the temperature and TCP profiles were also assessed and explained in terms of ohmic drops and electrokinetic processes.