Electrochemical sterilization of bacteria adsorbed on granular activated carbon

Abstract

The electrochemical sterilization of bacteria adsorbed on granular activated carbon (GAC) was demonstrated. The survival ratio of bacteria on GAC was dependent upon the applied potential. The survival ratio of Escherichia coli, Staphylococcus aureus, Bacillus subtilis and Saccha-romyces cererisiae vs. saturated calomel electrode (SCE) was below 1% at 0.75, 0.8, 1.0 and 0.65 V, respectively. The electrochemical sterilization of tap water containing E. coli was carried out when 3.5 ml of the cell suspension (4.0× 10-~ cells/ml) was incubated with 2.0 g of GAC for 5 h at [1.7 V vs. SCE. The number of E. coil adsorbed on GAC and the cell concentration in the water decreased rapidly. E. coli pp. GAC were electrochemically killed and the cell numbers did not increase.