金属镍中空纤维膜表面处理及其透氢性能

Surface modification of metal nickel hollow fibre membranes and its hydrogen permeability

为提高金属镍中空纤维膜的氢气渗透性能,利用干湿纺丝法和高温烧结工艺制备致密的金属镍中空纤维膜,并采用物理打磨、硝酸刻蚀以及化学镀钯的方法对其外表面进行处理。结果表明:物理打磨外表面后,镍膜壁厚由初始的0.09 mm减小到0.04 mm,减小了渗透阻力,渗透通量在1 000℃下达到20.48 mmol/(m^2·s);采用10%硝酸刻蚀40 min后,镍膜的厚度减小到0.05 mm,加快了氢气的扩散过程,氢气通量提高56.36%,增加至24.11 mmol/(m^2·s);化学镀钯后镍膜表面负载了钯层,使得氢气的溶解速度加快,氢气渗透通量高达23.15 mmol/(m^2·s)。

In order to improve the hydrogen permeability of metal nickel hollow fibre membranes,the dense metal nickel hollow fibre membranes were fabricated by dry-wet spinning and high-temperature sintering technique,and modified by physical grinding,nitric acid etching and electroless palladium plating.The results showed that after sanding the outer surface,the wall thickness of nickel hollow fibre membrane decreased from 0.09 to 0.04 mm,which reduced the penetration resistance and the permeation flux reached 20.48 mmol/(m^2·s)at 1 000℃.After the hollow fibre was etched by 10%nitric acid for 40 min,the thickness of nickel hollow fibre membrane was reduced to 0.05 mm,which accelerated the diffusion process of hydrogen and the hydrogen flux increased by 56.36%to be 24.11 mmol/(m^2·s).The Pd layer tightly attached to the nickel surface actually catalyzes the hydrogen dissociation,the hydrogen permeation flux was up to 23.15 mmol/(m^2·s).