Recent advances of sorption efficiency and mechanism of radionuclides on covalent organic frameworks materials

Abstract

<p indent="0mm">As the main force of new energy, nuclear energy is widely used in the world because of its high energy density, high efficiency and cleanness. However, a large number of radioactive substances produced from mining, processing of uranium (as main raw material of nuclear energy) and reprocessing of spent fuel will be released into environment through leaks and other ways. Owing to the high chemical toxicity and strong radioactivity, the releases of radioactive substances pose a potential threat to the environment and human health. Therefore, the efficient enrichment and separation of radioactive substances play a key role in the sustainable development of nuclear energy. As a main separation method, adsorption is widely used in the removal of radionuclides. Covalent organic frameworks (COFs) materials have good application towards adsorption of radioactive substances due to their high chemical stability, controllable structure and high specific surface area. In this review, the adsorption behavior and interaction mechanism of UO₂²⁺, TcO₄⁻, I⁻ and other radionuclides from aqueous solution on COFs and their composites under different environmental conditions are reviewed in details. At last, the challenges and prospective in adsorption of radionuclides by COF materials in environmental remediation are put forward.