1e:T4d6,Used nuclear fuel reprocessing represents a unique challenge when dealing with radionuclides such as isotopes of ⁸⁵Kr and ¹²⁹I₂ due to their volatility and long half-life. Efficient capture of ¹²⁹I₂ ( t_1/2 = 15.7 × 10⁶ years) from the nuclear waste stream can help reduce the risk of releasing I₂ radionuclide into the environment and/or potential incorporation into the human thyroid. Metal organic frameworks have the reported potential to be I₂ adsorbents but the effect of water vapor, generally present in the reprocessing off-gas stream, is rarely taken into account. Moisture-stable porous metal organic frameworks that can selectively adsorb I₂ in the presence of water vapor are thus of great interest. Herein, we report on the I₂ adsorption capacity of two microporous metal organic frameworks at both dry and humid conditions. Single-crystal X-ray diffraction and Raman spectroscopy reveal distinct sorption sites of molecular I₂ within the pores in proximity to the phenyl- and phenol-based linkers stabilized by the I···π and I···O interactions, which allow selective uptake of iodine.1f:T417,The efficient and safe capture of radioactive iodine (¹²⁹I or ¹³¹I) is of great significance in nuclear waste disposal. Here, we report millimeter-scale poly(ether sulfone) composite beads loaded with porous Cu-BTC [Cu₃(BTC)₂, BTC = 1,3,5-benzenetricarboxylate] (Cu-BTC@PES), prepared by a phase inversion method for the removal of volatile iodine. Three kinds of Cu-BTC@PES composite beads were obtained with different Cu-BTC contents of 48.6, 60.2, and 71.9%, respectively. While maintaining crystallinity, the composite beads exhibited higher I₂ vapor adsorption capacity (639 mg/g) in the form of iodine molecules. The iodine absorption up to 260 mg/g and the adsorption was followed Langmuir isotherm and pseudo-second-order kinetic model. Furthermore, the composite beads can still absorb more than 85% of iodine after 3 cycles of regeneration with excellent recyclability. The resulting Cu-BTC@PES composite beads show great potential for the sustainable removal of radioactive iodine.

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