Tetraethylene glycol-based polymer networks for the efficient removal of radioactive methyl iodide and iodine vapor

Abstract

Capturing radioiodine species produced during nuclear fuel reprocessing and nuclear accidents is crucial for nuclear safety, environmental protection, and public health. Here, we synthesized three tetraethylene glycol-based polymers, which were used to prepare polymer/pyridine gels for the efficient adsorption of methyl iodide. The adsorption capacities of the gels for methyl iodide were between 1.685 g/g_gel (equivalent to 11.256 g/g_polymer) and 1.575 g/g_gel (equivalent to 34.571 g/g_polymer), which were higher than those of other adsorbents reported thus far. Further investigation showed that this effective adsorption occurred via the reaction between pyridine and methyl iodide to form a pyridinium salt. These polymers also captured iodine vapor with moderate adsorption capacities of 2.492–2.990 g/g_P3via charge-transfer interactions between electron-rich sites and I₂. The present work uncovered an efficient route for adsorbing methyl iodide and thus demonstrated a new application for tetraethylene glycol-based polymers.