Keywords: electrokinetics, chemical oxidation, potassium permanganate, low-permeability soils, remediation, organics, clays, kaolin, oxidant transport, organic pollutants, electroosmosis, electromigration, electric potential, waste management, environment, environmental pollution, environmental management
Electrokinetic delivery of permanganate into low-permeability soils
A bench-scale study was conducted to investigate the feasibility of using electrokinetics as a method of delivering an oxidant into kaolin, a low-permeability soil. Potassium permanganate (KMnO4) was chosen as the oxidant, and in separate tests, KMnO4 was introduced at the anode, the cathode and both electrodes to investigate (1) the extent of oxidant transport via electroosmosis and electromigration and (2) to investigate the stability of the oxidant at each electrode location. Separate tests were performed under different voltage gradients to explore the effect of electric potential on oxidant transport and stability. Results indicate that (1) electromigration is not as effective as electroosmotic advection for the transport of permanganate into the soil and (2) permanganate may not be stable under the pH-redox conditions that are imposed by the application of electric potential. Additional research is being conducted to explore the stability of permanganate under electrokinetic environments and to determine whether a substantial amount of permanganate can be injected into low-permeability subsurface conditions.