Disinfection Performance and Mechanism of the Carbon Fiber-based Flow-Through Electrode System (FES) towards Gram-negative and Gram-positive Bacteria
2020
Abstract The disinfection performance of a carbon fiber-based flow-through electrode system (FES) towards Gram-negative bacteria (Escherichia coli and fecal coliform) and Gram-positive bacteria (Enterococcus faecalis and Bacillus subtilis) in normal saline was systematically investigated over a wide range of applied voltages (1-5 V) and hydraulic retention times (HRTs) (1-10 s). It was revealed that the Gram-negative bacteria were more vulnerable to FES for their thinner cell walls, and over 6.5 log removal (no live bacteria detected) was achieved at the applied voltage of 2 V and HRT of 2 s; while Gram-positive bacteria were inactivated at slightly higher voltages (3 V, 2 s) or longer HRTs (2 V, 5 s). Bacterial inactivation was attributed to the change and rupture of cell membrane mainly by anode direct oxidation without bacterial regrowth/reactivation. In addition, negligible generation of the free chlorine at low voltages (≤ 2 V) can avoid the formation of potential chlorinated disinfection byproducts (DBPs). Hence, FES can offer a potential alternative to conventional disinfection methods for bacteria inactivation in natural and contaminated water.
Keywords:
- Correction
- Source
- Cite
- Save
- Machine Reading By IdeaReader
38
References
8
Citations
NaN
KQI