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[Display omitted] • Hydrophobic interactions and hydrogen bonded self-assembly achieve mild functionalization. • The membrane is with anti-fouling, anti-bacteria, and anti-adhesion properties. • The membranes could maintain 85% of adsorption capacity with various interferences. • The membranes could obtain 1.15 mg/g of uranium when the concentration is 3.3 ppb. Herein, we have developed a mild and convenient strategy to enable polypropylene (PP) fibrous membranes with abundant adsorption sites for the selective extraction of uranium from seawater. Lysozyme was chosen as the pre-coatings because of its strong hydrophobic interactions with PP membranes. Then, lysozyme and phytic acid were set as hydrogen bonding self-assembling components since both of them are proved with a great binding affinity towards uranium. The contents and thickness of the lysozyme-phytic acid coatings could be linearly tuned due to the excellent controllability of self-assembly. The obtained PP membrane could achieve adsorption capacity as high as 90.07 mg-U/g-membrane (2143.83 mg-U/g-coating). In addition, the lysozyme would endow the PP membranes with outstanding anti-fouling, anti-bacteria, and anti-adhesion properties. The modified membranes could maintain more than 85% of adsorption capacity even with the interferences of bacteria and model pollutants. We also applied the membranes for dynamic adsorption by taking advantage of membrane filtrations. The adsorption capacity during the dynamic process increases with the flow rates and the layer numbers because more uranyl ions could contact with the adsorption sites. The modified PP membranes could obtain 1.15 mg/g of uranium after 15 days when the concentration of uranium is set as the same as the uranium concentration (3.3 μg/L) in natural seawater. [ABSTRACT FROM AUTHOR]

[Display omitted] • Cellulose-based absorbents with the highest reported uranium uptake are achieved. • Homogeneous reactions are beneficial to grafting density and material utilization. • Excellent hydrophilicity contributes to rapid mass transfer and antifouling property. • The adsorbents could be filled into filtration columns for dynamic adsorption. • The adsorbents collect 50 mg uranium/g from simulated seawater in 24 d adsorption. Highly efficient extraction of uranium from seawater is regarded as an important guarantee for the promotion of nuclear electricity generation. Amidoxime based adsorbents are considered as the most promising materials for uranium recovery due to their high selectivity and binding capability to uranyl ions. Herein, natural celluloses with advantages of low cost, biodegradability, renewability were chosen as the raw materials. Moreover, amidoximated cellulose-based adsorbents are fabricated by two steps of homogeneous reactions including the Michael addition and amidoximation reaction. Compared with traditional surface grafting methods, both the grafting density of active adsorption sites and the utilization of raw materials could be greatly improved because of the lower steric hindrance as well as more exposed reactive sites during the homogeneous reactions. The adsorption capacity of our adsorbents can reach as high as 517.07 mg/g at pH = 7, one of the best cellulose-based adsorbents as far as we know. In addition, excellent hydrophilicity of the adsorbents, which is inherited from the natural cellulose, can endow them with enhanced mass transfer as well as resistance to marine pollutants. More importantly, the adsorption microspheres would be filled into filtration column for dynamic adsorption benefited from their aforementioned merits. The average adsorption capacity could maintain above 2.5 mg/g per day when the filtration column was exposed to simulated seawater for 24 days. All these characteristics make the amidoximated cellulose-based adsorbents potentially applicable to the uranium recovery from seawater. [ABSTRACT FROM AUTHOR]