Aizo Yamauchi

Immobilization of biocatalysts with poly(vinyl alcohol) supports

Two polymer materials, poly(vinyl alcohol) (PVA) superfine fibers and photocrosslinkable PVA bearing styrylpyridinium groups, have been developed to immobilize biocatalysts. The former has a large surface consisting of relatively large-size pores and the fibers can immobilize a large amount of biocatalyst on their surface by ionic interaction. The latter entraps many kinds of biocatalysts by cyclodimerization caused by visible light irradiation. The biocatalysts on/in these supports maintain high activity and thermal stability. These materials can easily be formed into various shapes suitable for various applications. A new bioreactor system was constructed for evaluating a variety of biocatalysts and supports.

Thermoresponsive Polymer Hydrogel

In recent years, materials responding external stimuli have become of major interest and have been applied to sensor or memory media.

Preparation of new support for immobilization of activated sludges

A new support was prepared by the combination of an oxygen enrichment hollow fiber membrane and fibrous support for immobilization of activated sludge microorganisms. A biofilm of activated sludges immobilized and grown on the support were shown to be highly active. It was confirmed that a wastewater treatment method using this new support was efficient for TOC and TN removal.

Oxygen transfer from silicone hollow fiber membrane to water

Silicone rubber hollow fiber was able to enrich the oxygen concentration in air by about 30%, and oxygen was transferred sufficiently from the membrane to water. When an aeration tank was filled with hollow fiber to up to 10% of its volume, the oxygen utilization rate, Rr, was about seven times as much as the value in the standard activated sludge method. It is suggested that there is some possibility of improving the efficiency of aerobic wastewater treatment by using this system.

Immobilization of Bioactive Substances with PVA Supports

A variety of methods and materials for immobilizing biocatalysts have been proposed and tested. All of the different methods or materials has some advantages and disadvantages. No one technique or support seems to have a clear edge over the others. In any case, the technique or support, which can make the most of the advantage and minimize the disadvantage, should be selected.