Highly permeable porous YSZ hollow fiber membrane prepared using ethanol as external coagulant

Highly permeable porous yttria-stabilized zirconia (YSZ) hollow fiber membranes have been developed by a combined phase inversion and sintering technique. Ethanol substituting for usual water was used as the external coagulant in order to prepare YSZ hollow fiber membranes with low trans-membrane resistance. The prepared YSZ hollow fiber membranes show a special asymmetric structure with an outer skin layer, highly porous inner surface and sub-layer composed of long and large finger-like pores. The influences of sintering temperature on the microstructure, porosity and pore size distribution, bending strength and pure water flux were investigated in detail. Results show that YSZ hollow fiber membranes with high permeability and enough bending strength can be prepared using ethanol as the external coagulant and by controlling the sintering temperature. The outer-skinned YSZ hollow fiber membranes show a pure water flux of 2.27-4.30 m³ m^-2 h^-1 bar^-1 and a bending strength of 154.5-201.7 MPa when sintered between 1350 and 1400 °C. The prepared YSZ hollow fiber membranes are suitable to be used for microfiltration and as support for other composite membranes.