Electrokinetics and activated carbon: innovative synergy for sediment remediation

The remediation of contaminated dredged sediments remains crucial for enhancing environmental quality. Electrokinetic remediation is an environmentally friendly technology enabling the migration of pollutants from the sediment matrix. This article presents a laboratory study dedicated to examining the efficacy of electrokinetic remediation on the mobility and removal of heavy metals from dredged sediments, using a combination of chelating agents and surfactants coupled with activated carbon particles. The uniqueness of this study lies in the insertion of a third electrode, in the form of particles, directly into the sediment matrix. Results indicate that activated carbon particles positively affect the voltage gradient, increasing it by up to 1169%. Combined with citric acid, activated carbon particles increased electro-osmotic flow rates and promoted flow in the conventional direction. Utilizing the conductivity of activated carbon could be an economically viable alternative to reduce electric current consumption in EK tests and improve remediation levels. However, a variety of sediments, activated carbons, and reagents (citric acid and surfactants) must be tested to determine optimal usage conditions.