Chemical conditioning of electrode reservoirs during electrokinetic soil flushin

2019-05-14 19:18:14

soil Pb HCl cathode HAc

责任者: Reed, Brian E.;Berg, Mitchell T.;Thompson, John C.;Hatfield, Jarrod H. 单位: West Virginia Univ, Morgantown, WV, USA 来源出处: Journal of Environmental Engineering,1995,121(11):805-814 摘要: The in-situ remediation of a lead-contaminated soil (silt loam, KH = 5 × 10-8 cm/s, soil Pb = 1,000 mg/kg) by electrokinetic (EK) soil flushing [60 V (DC)] was studied. Research focused on the chemical conditioning of the electrode reservoirs with either 500 μS/cm (as NaNO3, baseline behavior), acetic acid (HAc), HCl, or EDTA. For baseline tests there were significant amounts of lead transported through the soil, but the Pb precipitated or was readsorbed on the soil adjacent to the cathode because of the high soil pH in that region. The addition of 1 M HAc to the cathode reservoir prevented the formation of the basic conditions in the soil, and about 65% of the Pb was transported into the cathode. When HCl was added to the anode and HAc was added to the cathode, more than 75% of the lead resided in the cathode. Pb removals in the EDTA experiments were greater than those observed in the baseline experiments and were similar to those observed in the HCl-HAc experiments. A low anode reservoir pH resulting from a high current was the most likely reason. 关键词: Electrochemistry;Electrochemical electrodes;Osmosis;Contamination;Lead;Soils;pH;Flow of fluids;Silt;Electrode reservoirs;Chemical conditioning;Remediation;Soil flushing;Electrokinetics;Loam;Electroosmosis