The immobilization of clostridium acetobutylicum by adsorbing on the inorganic carrier material and its application

In order to prevent the membrane fouling by cells during the in-situ recovery process of the pervaporation membrane, the immobilization of Clostridium acetobutylicum XY16 on different inorganic carriers and its effects on butanol fermentation were investigated. The results show that the zeolite can well adsorb the cell with negative charge, and the zeolite can be further modified by treating it with cationic modification. The zeta potential of zeolite surface was changed after the zeolite was modified by loading it with iron (III), then its efficiency of cells immobilization was increased, and the butanol production was enhanced. In the batch fermentation, when the glucose concentration in fermentation medium is 60 g·L^-1 and the added Fe³⁺-zeolite amount is 18% (W/V), the conversion ratio of the total solvent is 0.31 g·L^-1 and the immobilized efficiency is 87% which increases by 22%; the butanol concentration of 13.5 g·L^-1 and total solvent's of 20 g·L^-1 can be obtained, which increase respectively by 8% and 11.1% compared with those when unmodified zeolite is used. The batch fermentation experiment of immobilized cells by Fe³⁺-zeolite was repeated for four times, and each time the yield of total solvent is higher than that of batch fermentation with free cells. It shows that the Fe³⁺-zeolite is suitable to be used as immobilized carrier for butanol production by Clostridium acetobutylicum XY16.