The effect of critical operational parameters on the circulation-enhanced electrokinetics.
Electrokinetics (EK) is a technique for soil remediation. However, the acid produced due to the water electrolysis at the anode will cause soil acidification, which may destroy the soil constituents, and reduce contaminant removal efficiency. The formation of a base front produced at the cathode will result in the precipitation of metal hydroxides and a concomitant clogging of pore space. In this study, a circulation-enhanced EK (CEEK) system is designed to neutralize the pH of the working solution and soils for avoiding the above problems. Experiments are conducted by controlling different voltage gradients, electrode materials, and electrode emplacement, respectively. According to the experimental results, the CEEK system could effectively stabilize the current and the pH of processing solution at a neutral range. The strength of voltage gradient is proportional to the current magnitude of the CEEK system. The graphite electrode for CEEK is the better choice than the metal electrodes because graphite electrodes can achieve the lower electricity consumption. The electrode installed in the reservoir without attachment on soils can decrease the pH deviation of the soil matrix.
Chang
Jih-Hsing
JH
Department of Environmental Engineering and Management, Chaoyang University of Technology, 168 GiFeng East Road, WuFong Hsiang, 413 Taichung County, Taiwan. changjh@cyut.edu.tw
Liao
Ying-Chih
YC
D004553:Electric Conductivity; D004563:Electrochemistry; D006863:Hydrogen-Ion Concentration; D012987:Soil / Q000032:analysis*; D012989:Soil Pollutants / Q000302:isolation & purification*; D014867:Water / Q000032:analysis*
D012987:Soil; D012989:Soil Pollutants; D014867:Water