イオン交換膜電気透析法の殺菌機構

Disinfection mechanism of electrodialyis system using ion exchange membranes has been investigated. One hundred minion (108) cens/cm3 of E. coli cells suspended in 0.1-0.6 M NaCl aqueous solution were passed through a desalting chamber at aflow rate of 3cm3/min at various current densities (0.27-1.63 A/dm2) in the visinity of the limiting current density (0.81A/dm2).
Intensities of electric field in the desalting chamber of each condition were calculated from measured values of electric potentials, and from the caluculated values relasionship between intensity of electric field and disinfection effbct were investigated.
In the both cases of changing current density and NaCl concentration, it was found that vaibility of cells percentage (%) decreased with an increase in the intensity of electric field. E. coli cells in suspension were found to be completely disinfected over the value of 2.30 V/cm in the electric field intensities. The result sug gest that disinfection effects of electrodialysis system were deeply concerned with intensities of the electric field.
Electric conductivity of a E. coli cell was caLiculated from measured electrolyte amount, weight and water content in the E. coli cells, and compared with that of solution in the desalting chamber using 0.1 M NaCl suspension at the current density of 1.35A/dm2 where electric field strength was 2.30V/cm. From the experiment, it was cleared that electric conductivity(0.248S/cm)of the E. coli cell was about four time as large as that (0.0057S/cm) of NaCl solution in the desalting chamber.
Taking the results in to account'it was concluded that the disinfection mechanism of electrodialysis system is an electrochemical electric conduction effbct in the surface and inside of E. coli cells, over the condition of limiting current density (0.81A/dm2).