TIO2-MEDIATED PHOTOCHEMICAL DISINFECTION OF ESCHERICHIA-COLI USING OPTICAL FIBERS

We have constructed a system for photochemical disinfection of bacteri a using a suspension of titanium dioxide and diffuse-light emitting op tical fibers (DLEOFs). Disinfection of bacteria at high TiO2 concentra tions was light-limited when conventional optical fibers were used to supply light to the cell suspension. However, when using DLEOFs that e mit light laterally from their surface, light distribution throughout a suspension of Escherichia coli was greatly improved even in the pres ence of high TiO2 concentrations. A 4-fold increase in photochemical d isinfection was obtained at high TiO2 concentrations using DLEOFs rath er than conventional optical fibers for light supply. The use of DLEOF s should provide a generally applicable method for photodisinfection o f water supplies.