Abstract
Recently, biomass immobilization technique has been put to practical use in advanced waste water treatment processes. The conventional immobilization technique, however, poses a problem with respect to mass transfer resistance for substrate and product molecules to the microorganisms inside immobilization gel matrices. The problem can be solved by utilization of functional gels as immobilizing media, which reversibly shrink and swell when external conditions change such as temperature, pH, and solvent composition. In this study, visible light-stimulus-responsive NIPA-CH (N-isopropylacrylamide-Chlorophyllin) gels were applied to examine a possibility of utilization in waste water treatment processes. The purpose of this study is to investigate physical properties of NIPA-CH gels such as swelling ratios, repetitive behaviors, and the influence of the swelling capacity on the immobilized microorganisms. The NIPA-CH gels showed sufficient swelling ratios under cyclic visible light stimuli, and it was suggested that the mass transfer of substrates would be enhanced by the shrinking and swelling effects of the visible light-stimulus responsive NIPA-CH gels.
