Notice of RetractionInactivation Kinetics of Adsorptive Bacteria with Free Chlorine in GAC Treatments

Notice of Retraction

After careful and considered review of the content of this paper by a duly constituted expert committee, this paper has been found to be in violation of IEEE´s Publication Principles.

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The documented release of carbon fines from granular activated carbon (GAC) filters has high resistance to chlorination and may adsorb plentiful bacteria through the disinfection barrier. But it is not known the course of resistance and primary and secondary influencing factors. Using response surface analysis and numerical model, we determined the optimal levels of the main factors and detected the disinfection efficiencies and kinetic inactivation models of attached bacteria and fines. Under the optimal conditions, the disinfection efficiencies increased from 40-50% to 89%. Largest disinfection efficiencies were obtained at mild particles level (200 CNT/ml) and disinfection efficiencies (1.507 mg·L^-1). The prolong time of the chlorine contact time had almost no effect on the disinfection efficiencies. Using two-parameter dynamic model, the main reaction constants of chlorination were determined. And the reaction of chlorine was the first order reaction (n=1) with rate constant k₂ of 0.6897. Average reaction activation energy with chlorine was only 15.048kJ/mol. The appropriate disinfection range of HOCl was at pH6.5-7.8 for adsorptive bacteria. The results showed that under the conditions of conventional water treatment, the action of chlorine dosing to control adsorptive bacteria in GAC effluent was limited.