聚醚砜分子量对相转化法YSZ中空纤维陶瓷膜结构与性能的影响

Effect of PES Molecular Weight on Microstructure and Properties of YSZ Hollow Fiber Membranes Derived from Phase Inversion Method

采用不同分子量聚醚砜(PES)作为聚合物结合剂,通过相转化法和高温烧结制备了非对称结构YSZ中空纤维陶瓷膜。研究了不同分子量聚醚砜制备的铸膜浆料粘度变化对相转化过程及膜的微观结构与孔隙率和孔径、纯水和氮气渗透通量及抗弯强度等性能的影响。结果表明,采用分子量较小的PES制备的中空纤维膜由内侧大指孔结构和外侧小指孔结构构成。随着PES分子量和铸膜浆料粘度提高,外侧指孔长大而内侧指孔减小,且出现明显的中间海绵层。随着浆料粘度提高,膜孔隙率明显下降。采用PES E3010作为聚合物原料时,制备的YSZ中空纤维膜具有最大的外表皮层分离孔径,表现出最高的渗透性能和抗弯强度,在1400℃保温3 h烧结时,膜纯水通量和抗弯强度分别可达到9.35 m^3/(m^2·h·MPa)和113.9 MPa。

Polyethersulfone （PES） with different molecular weights were used as polymer binder to fabricate the asymmetric structure yttria- stabilized zirconia （YSZ） hollow fiber membranes by a combined phase inversion and sintering technique. The effect of PES molecular weight on the viscosity of suspensions and the resultant membrane microstructure and porosity, pore size, pure water and nitrogen fluxs, bending strength were investigated. Results show that when PES with low molecular weight was applied, the prepared membrane was composed of inner large finger-like pore structure and outer small finger-like structure layers. With the increase of PES molecular weight, the outer finger- like pores enlarged, while the size of inner finger-like pores decreased, and sponge-like structure layer occurred in the middle of the membrane wall. The porosity of the prepared membrane decreased with the increase of suspension viscosity. The YSZ hollow fiber ceramic membrane derived fxom PES E3010 showed the largest pore size of outer skin layer, and demonstrates the highest permeate flux and bending slrength. When sintered at 1400 ℃ for 3 h, the pure water flux and bending strength of 9.35 m3/（m2 ·h·MPa） and 113.9 MPa can be obtained, respectively.