Stichnothe, Heinz; Czediwoda, Anette; Schönbucher, Axel:

Electrokinetic removal of cadmium from fine-grained soil.

In: Environmental Geotechnology, Proceedings of the International Symposium, 3rd, San Diego, June 9-12, 1996, Jg. 1 (1996), S. 780-785
Zeitschriftenaufsatz / Fach: Chemie
The electrokinetic remediation process offers a promising possibility for the removal of contaminated soil, if a cation exchange resin is employed. The pH gradient in the soil is a result of the electrokinetic soil treatment. Without regulation of the pH value metals will ppt. as hydroxide or carbonate and that causes a redn. of the electroosmotic flow. Normally, this problem is solved by a circulation system of the electrode compartments, this, however, produces great amts. of waste water . To avoid this problem, it is useful to employ a cation exchange resin in front of the cathode. The cations arriving at the resin will then be exchanged against protons, which neutralize the hydroxyl-ions that are produced at the cathode. The removal of 95-100% Cd from contaminated kaolin clay with different contents of com. available humic acid in lab. scale is shown and discussed.