ELECTROCHEMICAL DISINFECTION OF MARINE-BACTERIA ATTACHED ON A PLASTIC ELECTRODE

A plastic electrode, which consisted of graphite and silicone rubber, was employed for the electrochemical disinfection of attached marine bacteria, Vibrio alginolyticus. The viability of the bacteria attached on the electrode depended on the applied potential and time. Marine bacteria attached on a basal plane pyrolytic graphite electrode could be disinfected at potentials above 0.8 V vs. a saturated calomel electrode (SCE) applied for 20 min. The bacteria attached on a graphite-silicone electrode were disinfected at 1.0 V vs. SCE and 1.5 V vs. SCE, and 5.6 x 10(3) cells/cm2 of attached bacteria were disinfected to less than 5% of the initial number at times above 10 min. The residual chlorine concentration was less than the regulated value (0.02 ppm) and the pH value did not change after a potential of 1.5 V vs. SCE was applied to the graphite-silicone electrode for 30 min.