采用干湿相转化法纺制了聚砜(PSF)中空纤维超滤底膜,并采用溶液浸渍法制备PDMS/PSF中空纤维复合膜.研究了PDMS膜的溶胀性能和PDMS/PSF膜渗透汽化性能,考察了PDMS/PSF膜的稳定性以及料液温度、料液丙酮浓度和渗透物侧压力等因素对膜渗透汽化性能的影响.结果表明,PDMS膜对丙酮有很强的吸附能力而对水的吸附能力则相对较弱,渗透液中丙酮浓度大于膜溶胀液中丙酮浓度,远远大于浸泡液中丙酮浓度,连续操作72 h膜的渗透汽化性能保持稳定,渗透通量随料液温度以及料液浓度的升高而增加,分离系数随料液浓度的增加而降低,基本不受温度的影响.当丙酮质量分数5％、料液温度为60℃时,渗透通量为632 g/(m2·h),分离系数为35.8,丙酮和水的表观活化能分别为45.7和49 kJ/mol.%Polysulfone (PSF) ultrafiltration hollow fiber base membranes were fabricated by the dry/wet-spinning method PDMS/PSF hollow fiber composite membranes were prepared by coating PDMS solution on the outer surface of PSF ultrafiltration membranes using dip-coated method. PDMS swelling behavior and pervaporation performance of PDMS/PSF membranes were studied. PDMS/PSF membranes were used to separate dilute acetoneaqueous solution by pervaporatioa Membrane stability and the effects of feed temperature, feed concentration and permeate pressure on membrane performance were studied. Working for 72 hours continuously, the pervaporation performance of PDMS/PSF membrane kept stable. Swelling experiments show that PDMS membrane has a strong adsorption capacity to acetone and a weak absorption capacity to water; acetone concentration in permeate is greater than that in the swelled membranes and is largely greater than that in soaking solution. Permeate flux increases with the increasing of feed temperature and feed concentration. Separation factor decreases with the increasing of feed concentration and is independent of feed temperature. When acetone mass fraction is 5 %, permeation flux is 632 g/(m2 · H) and separation factor is 37. The apparent activation energy of actone and water were 45. 7 and 49 kj/mol, respectively.
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