Fabricating Porous Alkali-Resistant Resin for Segregation of Perrhenate/Pertechnetate Anions from Wastewater

The elimination of the β-emitting pertechnetate ion (⁹⁹TcO₄^-) from highly alkaline tank waste poses a daunting challenge that is of great significance for nuclear safety and environmental protection. Herein, we report a strategy to fabricate an alkaline-stable porous resin (PANPEI-MeCl) that features hyperbranched quaternary amine groups grafted on the surface and confined within the pores of a superhydrophobic polymer matrix synthesized by a one-pot method, exhibiting a clear superiority both in adsorption kinetics and efficiency compared with available commercial anion-exchange resins applying to ⁹⁹TcO₄^- capture. Notably, the alkaline stability of the resin can be improved by manipulating the length of side chain alkyl groups, and it shows ultrahigh structural integrity and prominent performance toward acid/alkaline soaking, high-temperature calcination procedures, and high doses of ionizing radiation. Encouraged by its excellent peculiarity, PANPEI-MeCl can continuously capture most of the ReO₄^- from the simulated radioactive waste by using a sequential injection automatic separation system.