During the last two decades, electrocoagulation (EC) process has known a large success as an electrodisinfection (ED) technology especially if iron (Fe) electrodes are used instead of aluminum ones as sacrificial anodes. This review discusses the pertinent findings of the Delaire et al. excellent work who focused on microbes removal via Fe-EC and attracted the attention on the interactions between bacterial phosphate groups and Fe (III) precipitates. Employing the model indicator Escherichia coli, physical elimination through enmeshment in EC precipitate flocs was shown the main procedure of bacteria reduction in the existence of HCO3-, which importantly prevents demobilization, probably because of a decrease in the lifetime of reactive oxidants. The fixation of EC precipitates onto cell membranes, which leads to microbes’ encapsulation in flocs, is directed firstly via interactions among EC precipitates and phosphate functional groups on bacteria surfaces. EC precipitate fixation is greatly independent of cell membrane composition, consistent with comparable densities of phosphate functional groups on Gram-positive and Gram-negative cells. Such findings are crucial to anticipate the efficiency of Fe-EC to remove bacterial pollutants from the water with changing chemical compositions. In spite of the huge advances in studying the EC process as an ED technique, considerable efforts remain to be performed to reach its better acceptation in the industrial world.
Iron Electrocoagulation Process for Disinfecting Water – A Review, Applied Engineering.
Vol. 3, No. 2,
2019, pp. 154-158.
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