State Key Laboratory of Marine Resource Utilization in South China Sea, Hainan University, Haikou 570228, P. R. China.
Research Institute, Zhejiang University-Taizhou, Taizhou 318000, P. R. China.
ACS Appl Mater Interfaces. 2021 May 12;13(18):21272-21285. doi: 10.1021/acsami.1c02882. Epub 2021 May 4.
Although eco-friendly amidoxime-based adsorbents own an excellent uranium (U)-adsorption capacity, their U-adsorption efficiency is commonly reduced and even damaged by the biological adhesion from bacteria/microorganisms in an aqueous environment. Herein, we present an antibiofouling ultrathin poly(amidoxime) membrane (AUPM) with highly enhanced U-adsorption performance, through dispersing the quaternized chitosan (Q-CS) and poly(amidoxime) in a cross-linked sulfonated cellulose nanocrystals (S-CNC) network. The cross-linked S-CNC not only can elevate the hydrophilicity to improve the U-adsorption efficiency of AUPM but also can enhance the mechanical strength to form a self-supporting ultrathin membrane (17.21 MPa, 10 μm thickness). More importantly, this AUPM owns a good antibiofouling property, owing to the broad-spectrum antibacterial quaternary ammonium groups of the Q-CS. As a result, within the 1.00 L of low-concentration (100 ppb) U-added pure water (pH ≈ 5) and seawater (pH ≈ 8) for 48 h, 30 mg of AUPM can recover 93.7% U and 91.4% U, respectively. Furthermore, compared with the U-absorption capacity of a blank membrane without the Q-CS, that of AUPM can significantly increase 37.4% reaching from 6.39 to 8.78 mg/g after being in natural seawater for only 25 d. Additionally, this AUPM can still maintain almost constant tensile strength during 10 cycles of adsorption-desorption, which indicates the relatively long-term usability of AUPM. This AUPM will be a promising candidate for highly efficient and large-scale U-recovery from both U-containing waste freshwater/seawater and natural seawater, which will be greatly helpful to deal with the U-pollution and enrich U for the consumption of nuclear power. More importantly, the work will provide a new convenient but universal strategy to fabricate new highly enhanced low-cost U-adsorbents, through the introduction of both an antibacterial property and a high mechanical performance, which will be a good reference for the design of new highly efficient U-adsorbents.
尽管环保的偕胺肟基吸附剂具有出色的铀（U）吸附能力，但在水相环境中，它们的 U 吸附效率通常会因细菌/微生物的生物附着而降低甚至损坏。在此，我们通过将季铵化壳聚糖（Q-CS）和聚偕胺肟（PAO）分散在交联磺化纤维素纳米晶体（S-CNC）网络中，制备了具有高增强的 U 吸附性能的抗生物污染超薄聚偕胺肟膜（AUPM）。交联的 S-CNC 不仅可以提高亲水性，从而提高 AUPM 的 U 吸附效率，还可以增强机械强度，形成自支撑的超薄膜（17.21 MPa，10 μm 厚）。更重要的是，由于 Q-CS 的广谱抗菌季铵基团，这种 AUPM 具有良好的抗生物污染性能。结果，在 1.00 L 低浓度（100 ppb）添加 U 的纯水（pH ≈ 5）和海水中（pH ≈ 8）中 48 h 后，30 mg 的 AUPM 分别可以回收 93.7% U 和 91.4% U。此外，与没有 Q-CS 的空白膜的 U 吸附容量相比，在天然海水中仅 25 d 后，AUPM 的 U 吸附容量从 6.39 增加到 8.78 mg/g，可显著增加 37.4%。此外，在 10 次吸附-解吸循环中，AUPM 的拉伸强度几乎保持不变，这表明 AUPM 的长期可用性。AUPM 将是从含 U 淡水/海水和天然海水中高效、大规模回收 U 的有前途的候选材料，这将极大地有助于处理 U 污染和为核能消耗富集 U。更重要的是，该工作将提供一种新的简便但通用的策略来制备新的增强型低成本 U 吸附剂，通过引入抗菌性能和高机械性能，为设计新型高效 U 吸附剂提供了良好的参考。
