新型渗透蒸发膜聚甲基双苯基硅氧烷膜的制备和分离

Preparation and separation of novel pervaporative membrane——Polymethyldiphenylsiloxane membrane

采用2种不同配方制备出苯基含量不同的聚甲基双苯基硅氧烷(PMPhS)膜并用于分离苯-水体系。接触角测定结果表明2种膜比PDMS膜亲苯疏水性增强。以渗透通量和分离因子为评价指标,研究了原料液温度、流动状况、质量分数、膜下游侧压力对渗透蒸发分离性能的影响,结果表明,随着原料液温度、流速以及料液浓度的提高,通量和分离因子都增加,随着下游侧压力的升高,通量和分离因子均降低。

Polymethyldiphenylsiloxane （PMPhS） membranes with different phenyl contents were prepared from two different recipes for the benzene/water mixture separation. The thickness of unswelling PMPhS membrane is 50- 300 μm. Contact angle measurement indicates that the membranes are more hydrophobic and of higher benzene solubility than polydimethylsiloxane （PDMS）. The effects of feed temperature, feed flowing state, feed mass fraction, and the downstream side pressure on the separation performance of membranes during pervaporation process were investigated by using permeation flux and separation factor as the evaluation index. Experimental results showed that with the increasing of feed mass fraction, feed flow rate, and feed temperature, the permeation flux and separation factor increased; with the increasing of downstream pressure, permeation flux and separation factor decreased.