丁醇发酵受产物丁醇的抑制,产率和产物浓度低,过程经济性差,为减轻丁醇的抑制,制备了聚二甲基硅氧烷/聚偏氟乙烯(PIMS/PVDF)复合膜用于丙酮-丁醇-乙醇-水体系有机成分的分离.以分离因子和渗透通量为评价指标,考察了料液温度、质量分数和pH值对复合膜渗透汽化分离性能的影响.结果表明:料液温度升高能提高膜的分离性能；料液质量分数的增加能增大复合膜的总渗透通量和丁醇的分离因子,但丙酮和乙醇的分离因子则有所降低；料液pH值的影响不明显.将复合膜应用于丁醇发酵过程,进行丁醇发酵与分离的耦合,使淀粉利用率提高了51.2％,溶剂质量分数提高了87.3％,耦合阶段生产强度达到了1.33 g/(L·h),提高了73.7％,并且丁醇在渗透液中得到浓缩.因此,所制备的PDMS/PVDF复合膜能够应用于丁醇发酵过程,显著提高丁醇发酵过程的经济性.%Butanol fermentation is inhibited by butanol product, leading to low productivity, low product concentration and poor economic feasibility. In order to decrease the inhibition of butanol, PDMS/PVDF membrane was prepared for separating acetone, butanol and ethanol from aqueous solutions. Taking separation factor and flux as evaluating index, the effects of feed temperature, mass fraction and Ph on pervaporation performance were investigated. The results indicate that the membrane separation performance ascends with increasing feed temperature; the increase of feed mass fraction improves the total flux and the separation factor of butanol but reduces the separation factors of acetone and ethanol; the Ph of feed liquid has little influence. By utilizing PDMS/ PVDF membrane in butanol fermentation, coupled with butanol fermentation and separation, the utilization ratio of cassava starch and the solvent mass fraction are increased by 51. 2% and 87. 3% , respectively. The production intensity during the period of coupling is 1.33 g/( L ? H) , increasing by 73.7% , and butanol is condensed in the penetrant. So the PDMS/PVDF membrane can be used for butanol fermentation, and the economics of butanol fermentation process can be improved.
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