Effect of alternating and direct current in an electrocoagulation process on the removal of cadmium from water

Central Electrochemical Research Institute, Karaikudi, India.
Water Science & Technology (Impact Factor: 1.11). 01/2012; 65(2):353-60. DOI: 10.2166/wst.2012.859
Source: PubMed


The main objective of this study was to investigate the effects of AC and DC on the removal of cadmium from water using iron as anode and cathode. The various operating parameters on the removal efficiency of cadmium were investigated. The results showed that the optimum removal efficiency of 98.1 and 97.3% with the energy consumption of 0.734 and 1.413 kWh/kL was achieved at a current density of 0.2 A/dm(2), at pH of 7.0 using AC and DC respectively. The adsorption process follows second order kinetics and the temperature studies showed that adsorption was endothermic and spontaneous in nature.

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    • "to complex precipitation kinetics, have a strong affinity with dispersed/dissolved ions as well as the counter ions to cause coagulation/adsorption. The advantages of EC include high removal efficiency, a compact treatment facility, relatively low cost, and the possibility of complete automation (Vasudevan and Lakshmi, 2011). "
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    • "Similarly the best results was obtained at pH 7 by Khosa et al. [13], Vasudevan et al. [6], Kumarasinghe et al. [15]and Kamaraj et al. [16] for the removal of heavy metal. "
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