Chemically Robust Functionalized MOF/Polymer Composite for Selective Sequestration of Higher-Valent Actinides from Simulated Nuclear Waste

Abstract

Due to the increasing global demand for energy, the development of nuclear energy becomes crucial because of its low carbon emission and high energy density output. Thorium and uranium are the main raw materials and energy resources for nuclear fission industries, and their improper disposal may cause a serious threat to the ecosystem. Herein, we strategically designed and fabricated a functionalized MOF/polymer composite via the in situ formation of a cross-linked polymer inside the cavity of MIL-101. The porous composite with high chemical and radiation stability and suitable functionality can extract Th(IV), Pu(IV), and U(VI) from highly acidic nuclear waste. The synthesized MOF/polymer hybrid adsorbents exhibit a maximum capacity of 823 mg/g and 679 mg/g, achieving a high distribution coefficient (Kd) of 2.48 × 105 and 1.64 × 105 mLg–1 for Th(IV) and U(VI), respectively, in the presence of other competing ions. This study not only shows the great potential of hybrid porous materials but also provides a fundamental approach to designing a functionalized adsorbent for extraction of higher-valent actinides, aiming toward sustainable development, CO2 free energy, and environmental remediation.