Polyethyleneimine (PEI) is a famous chelated reagent for heavy metal capture, but the soluble PEI immobilization always needs complicated chemical procedures. In this work, we explored a simple and green strategy for PEI immobilization and Pb(II) removal by polydopamine (PDA) polymerization. It relies on a cooperative adsorption, originated from the fixation of charged SO₃H groups inside polystyrene matrix, and in-situ formation of PDA adjugated PEI by simple reaction at ambient temperature. The PDA interface favors the formation of stable adjugated PEI, and the charged SO₃H groups can drive trace heavy metal ions from bulk solution to the vicinity of branched PEI. These hybrid adsorbents exhibit superior selectivity with a distribution coefficient of 5250 mL/g, rapid kinetics (∼50 mins) and satisfactory sorption-regeneration property in Pb(II) removal. An outstanding capacity of ∼6200 liters water/kg sorbent and trace effluent (<10 μg/L, WHO) was completed in the treatment of the Pb-contaminated stream. In addition, it also works efficiently for various metals, such as Fe(III), Cu(II) and Ni(II) removal. Our work therefore provides a new method for efficient PEI immobilization and brings a new perspective for mitigating the problem of diverse heavy metal contamination.

聚乙烯亚胺 (PEI) 是一种著名的重金属捕获螯合剂，但可溶性 PEI 的固定化总是需要复杂的化学程序。在这项工作中，我们探索了一种通过聚多巴胺 (PDA) 聚合来固定 PEI 和去除 Pb(II) 的简单绿色策略。它依赖于协同吸附，源于聚苯乙烯基质内带电 SO ₃ H 基团的固定，以及在环境温度下通过简单反应原位形成 PDA 调节的 PEI。PDA 界面有利于形成稳定的调节 PEI，带电的 SO ₃H 基团可以将痕量重金属离子从本体溶液驱动到支链 PEI 附近。这些混合吸附剂表现出优异的选择性，分配系数为 5250 mL/g，动力学快速（约 50 分钟）和令人满意的 Pb（II）去除吸附再生性能。在处理受铅污染的流中完成了约 6200 升水/kg 吸附剂和痕量流出物（<10 μg/L，WHO）的出色处理能力。此外，它还可以有效去除各种金属，例如 Fe(III)、Cu(II) 和 Ni(II)。因此，我们的工作提供了一种有效固定 PEI 的新方法，并为减轻多种重金属污染问题带来了新的视角。