Promising porous materials for 99TcO4− removal from nuclear wastes

Technetium-99 (99Tc) is a 𝛽-emitting isotope generated from the fission of 235U, present in the form of 99TcO4− in aqueous solution, interfering with valence state control during the uranium extraction and recovery process. The high mobility and volatility of 99TcO4− create a technical bottleneck in nuclear waste management. In recent years, various porous materials have been reported for 99TcO4− removal via adsorption, ion exchange, redox reaction, and so on. The goal of highly efficient removal of 99TcO4− could be achieved by the design of porous materials with specific structures, different porosity and functional groups. Furthermore, the adsorption-electrocatalytic strategy is a promising method for efficiently and selectively reducing 99TcO4−/ReO4− to Tc(VI)O3/Re(VI)O3, achieving continuous removal of 99Tc from nuclear waste. This perspective summarizes the techniques and materials for 99Tc removal based on the current research and aims to offer significant references for the treatment of nuclear waste.