The amidoxime-modified ultrathin polyethylene fibrous membrane (called as AFM) is prepared by a two-step graft polymerization method. The nano-sized particle structures are constructed on the AFM adsorbents surface after grafting. The adsorption behaviors of AFM adsorbent are studied by laboratory scale adsorption experiments. The adsorption results show that the adsorption of uranium by AFM is an endothermic spontaneous behavior without additional driving force. The AFM absorbent shows high specific surface area, good mechanical property and outstanding reusability of >12 cycles. Furthermore, the AFM adsorbent has a high uranium adsorption capacity of 147.38 mg/g in 8 ppm U-spiked simulated seawater for 96 h and 7.46 mg/g in natural seawater for 56 days. The results show that the degree of grafting (DG) and thickness of the membrane are the two key factors affecting the adsorption capacity. The adsorbent with thinner membrane thickness has a higher adsorption capacity at a moderate DG. This is because at moderate DG, the thinner the membrane is, the easier the adsorption sites are contacted by uranium ions. This work presents a novel membrane adsorbent with high uranium adsorption capacity and long service life, which shows significant application potential for uranium extraction from seawater.

偕胺肟改性超薄聚乙烯纤维膜（简称AFM）采用两步接枝聚合法制备。接枝后在 AFM 吸附剂表面构建纳米级颗粒结构。通过实验室规模的吸附实验研究了 AFM 吸附剂的吸附行为。吸附结果表明，原子力显微镜对铀的吸附是一种吸热自发行为，没有额外的驱动力。AFM 吸收剂具有高比表面积、良好的机械性能和 > 12 次循环的出色可重复使用性。此外，AFM 吸附剂在 8 ppm U-spiked 模拟海水中 96 小时具有 147.38 mg/g 的铀吸附能力，在天然海水中 56 天具有 7.46 mg/g 的高铀吸附能力。结果表明，接枝度（DG）和膜厚度是影响吸附能力的两个关键因素。膜厚度较薄的吸附剂在中等 DG 下具有较高的吸附容量。这是因为在中等 DG 下，膜越薄，吸附位点越容易与铀离子接触。该工作提出了一种新型膜吸附剂，具有高铀吸附能力和长使用寿命，在海水提铀方面显示出巨大的应用潜力。