Electrokinetics removing

Pamukcu, S., and Wittle, J. K. (1992) Electrokinetic Removal of Selected Heavy Metals From SoilEnvironmental Progress, AIChE, 11(4), 241-250. 

Ko, S.-O., Schlautman, M.A., and Carraway, E.R. (2000). Cyclodextrin-enhanced electrokinetic removal of phenanthrene from a model clay soil. Environ Sci. Technol., 34, 1535-1541. 

Ribeiro, A.B. and Mexia, J.T. (1997) A dynamic model for the electrokinetic removal of copper from a polluted soil.f. Hazardous Mat., 56, 257-271. 

R. E. Saichek and K. R. Reddy, Effects of System Variables on Surfactant Enhanced Electrokinetic Removal of Polycyclic Aromatic Hydrocarbons from Clayey Soils, Environ. Technol., 24, 503-515 (2003). 

Kim, S. O. and Kim, K. W. (2001). Monitoring of electrokinetic removal ofheavy metals in tailing soils using sequential extraction analysis. J. Hazard. Mater. 85(3), 195-211. 

Kim, S. O., Moon, S. H., Kim, K. W., and Yun, S. T. (2002b). Pilot scale study of the ex-situ electrokinetic removal of heavy metals from municipal wastewater sludges. Water. Res. 36, 4765-4774. 

Reddy, K. R., Xu, C. Y., and Chinthamreddy, S. (2001). Assessment of electrokinetic removal of heavy metals from soils by sequential extraction. J. Hazard. Mater. 84(2-3), 279-296. 

Numerous studies are reported on the electrokinetic removal of heavy metals from soils (Chapter 4). Many of these studies used ideal soils, often kaolinite, as a representative low-permeabiUty soil, which were spiked with a selected single cationic metal (such as lead and cadmium) in predetermined concentration. The spiked soil is loaded in a small-scale electrokinetic test setup and electric potential is applied. The transport and removal of the metal after specified test duration are determined. It is shown that cationic metals exist in soluble ionic form due to reduced pH near the anode regions and they are transported toward the cathode. However, when they reach near the cathode, they get sorbed or precipitated due to increased pH resulting from OH transport from the cathode. The actual removal from the soil is often negligible. 

Sequential approaches are developed where (a) anionic metals are removed first and then cationic metals when mixed metal contamination is present and (b) organic compounds are removed first followed by the removal of heavy metals when coexisting heavy metal and organic contaminants are found. For example, the simultaneous electrokinetic removal of inorganic and organic pollutants (SEKRIOP)... 

Pamukcu S, Wittle JK. (1992). Electrokinetic removal of selected heavy metals from soil. Environmental Progress ll(3) 241-250. 

Saichek RE, Reddy KR. (2003). Effect of pH control at the anode for the electrokinetic removal of phenanthrene from kaolin soil. Chemosphere 51(4) 273-287. 

Reddy KR, Saichek RE. (2004). Enhanced electrokinetic removal of phenanthrene from clay soil by periodic electric potential apphcation. Journal of Environmental Science and Health Part A 39(5) 1189-1212. 

Ribeiro AB. (1994). Electrokinetic removal of heavy metals from a polluted soil. In Cornett Course—Pollution Control and Removal of Pollutants (Nitrates, Nitrites, Heavy Metals) from surface and groundwaters. March 21-23, Lisbon, Portugal Instituto Superior Tecnico. 

On the Russian territory, some lands in the Urals and in Siberia are also contaminated by radionuclides. In the Ural region, heavily contaminated soils can be found along the valley of the river Techa (Fig. 5.7). Significant territory is contaminated by radionuclides around the manufacturing association Mayak (Table 5.6). Electrokinetic removal of the radionuclides on these territories is very urgent. 

The most efficient electrokinetic removal of radioactive nuclides from polluted ground can be achieved in combination with electrochemical leaching, that is, with... 

Soil pH plays an important role in the adsorption and desorption of pollutants and, ultimately, influences transport. Generally, the desorption of cationic metals would be enhanced by acidic conditions because of ion exchange reactions between hydrogen ions and cationics. However, anionic pollutants would be desorbed more easily in an alkaline condition than in an acidic environment, indicating that the process fluid should be changed for the electrokinetic removal of anionic pollutants. 

Electrokinetic removal of nitrate from saline soil has been reported by several research groups. Application of an electric potential over a saline soil field resulted in increased salt content in drainage water and salt accumulation near the cathode (Gibbs, 1966). In addition, it was found that solute movement increased with greater electrical voltage. Cairo, Larson, and Slack (1996) reported that nitrate concentration increased from anode to cathode in saturated soil as solute flowed toward a horizontal drainage tube located adjacent and parallel to the cathode after application of a direct current (DC) electrical potential in field lysimeter experiments. However, after the soil became unsaturated, continued electrical input resulted in nitrate movement toward the anode. 

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