Preparation and characterization of Ag-coated porous ceramic spheres for antibacterial activity of drinking water

초록

The metal silver has broad antibiotic activity toward Gram-positive, Gram-negative, fungal aerobic and anerobic microorganisms. Porous ceramic spheres for antibacterial activity of drinking water were prepared by gelcasting and pseudo-double-emulsion method. Metal silver on porous ceramic spheres was coated at various silver concentration in solution by impregnation method. The silver on porous ceramic spheres were characterized using various analytical method such as Atomic Adsorption Spcetrospopy(AAS), Scanning Electron Micrograph(SEM)-EDS and X-ray diffraction(XRD). Antibacterial activity of Ag-coated porous ceramic spheres was tested by shaking flask method and durability of media with devised reactors. The physical properties of porous ceramic spheres were as follows : total porosity : 78%, mean size of pores : 180㎛, windows size : 20～50㎛. Silver metals whose the mean size is range of 0.5～2.0㎛, were homogeneously coated in inner or outer pores of the porous ceramic spheres. Bacteria reduction rate and durability of Ag-coated media increased with the increasing silver content coated on the porous ceramic pellets. Moreover, the antibacterial activity against gram-negative was better than that against gram-positive. And the antibacterial possibility of Ag-coated ceramic spheres as a substitute was evaluated by durability test.