Modification of porous silica with activated carbon and its application for fixation of yeasts

Mixtures of small silica particles and activated carbon were heated at 1250 -1450 degreesC in an inert atmosphere to make nano- and macro-sized porous silica for incorporating yeast in the porous strucrure. Without activated c arbon, porous silica of 45-60% porosity and 15-30 mum pore diameter was pro duced with a specific surface area below 1 m(2)/g. By the addition of 8 wt% of activated carbon granules, the surface area of porous silica increased to 100 m(2)/g at 1250 degreesC. It was confirmed that there were micropores (1.2 nm) and mesopores(4.0 nm) due to activated carbon granules in porous s ilica when granule type activated carbon was used. However, in the case of activated carbon fiber, its micro- and mesoporous structure was destroyed i n the firing process. The fixation of Z. rouxii yeasts was promoted on the porous silica with activated carbon.