PNNL

Abstract

Technetium-99 (99Tc), predominantly present as pertechnetate (99TcO4-), is a challenging contaminant in nuclear waste from artificial nuclear fission. The selective removal of 99TcO4- from nuclear waste and contaminated groundwater is complex due to: (i) the acidic and intricate nature of high-level liquid wastes; (ii) the highly alkaline environment in low-activity level tank wastes, such as those at Hanford, and in high-level wastes at locations like Savannah River; and (iii) the potential for 99TcO4- to leak into groundwater, risking severe water pollution due to its high mobility. This review focuses on recent developments in advanced porous materials, including metal-organic frameworks (MOFs), covalent organic frameworks (COFs), and their amorphous counterparts, porous organic polymers (POPs).