Removal of mercury and methylmercury from contaminated soils by applying an electric field

In this study, the removals of the mercury and methylmercury by applying an electric field have been investigated. The experimental results show that the non-uniform distributions of the pH, conductivity and potential gradien t would be formed during the treatment. These unexpected distributions woul d slow down the removal ofcontaminants. So the mercury and methylmercury co uld be only reduced to about 73.6% and 59.4% after 100-day treatment, respe ctively. Thus, the enhancement by using buffer solutions or cation exchange membranes was conducted to avoid the back-migration of the OH- generated a t the cathode. The results show that the removal efficiencies of the mercur y could attain 88% or more and that of the methylmercury could reach to 94% or more after only 60-day treatments by using either buffer solutions or c ation exchange membranes.