Asymmetric alumina hollow fibres produced by the phase inversion/sintering method present advantages in that high area/volume ratios and low mass transfer resistances are achieved due to the geometric configuration and the pore size distribution, respectively. Here we characterise hollow fibres that were prepared with different internal coagulants and at different sintering temperatures. Additionally, a palladium membrane was deposited on these different hollow fibres and hydrogen permeabilities through them were compared. More fingers were obtained when a mixture of solvent with water was used as internal coagulant, instead of pure water. At the same sintering temperature, nitrogen permeance through the fibre was increased 5-fold when a mixture of solvent and water was used as internal coagulant instead of pure solvent, and the water flux was increased 7-fold. The decrease in the sintering temperature increased the water permeance through the fibre from 21.4 to 63.9 L h -1 m -2 kPa -1 , but decreased its mechanical strength from 74 to 41 MPa. The hydrogen permeance at 450 ?°C was increased from 5.54x10 -5 to 3.06 x10 -3 mol m -2 s -1 kPa -1 when using a more permeable hollow fibre as substrate. These results elucidate better conditions to fabricate hollow fibres that present low mass transfer resistances.
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机译：通过相转化/烧结方法生产的不对称氧化铝中空纤维的优点在于，分别由于几何构型和孔径分布，实现了高的面积/体积比和低的传质阻力。在这里，我们表征了用不同的内部凝结剂和不同的烧结温度制备的中空纤维。另外，钯膜沉积在这些不同的中空纤维上，并比较了通过它们的氢渗透率。当使用溶剂与水的混合物代替纯水作为内部凝结剂时，可获得更多的手指。在相同的烧结温度下，当使用溶剂和水的混合物代替纯溶剂作为内部凝聚剂时，通过纤维的氮气渗透率增加5倍，并且水通量增加7倍。烧结温度的降低使通过纤维的透水率从21.4 Lh -1 m -2 kPa -1增加到63.9 L h -1 m -2 kPa -1，但机械强度从74 MPa降低到41 MPa。当使用更具渗透性的中空纤维作为基材时，在450℃下的氢渗透率从5.54×10 -5增加到3.06×10 -3 mol m -2 s -1 kPa -1。这些结果阐明了制造具有低传质阻力的中空纤维的更好条件。
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