Rapid detection and absorption of 99 TcO 4 ⁻ contamination in the environment are critical due to its high radioactivity, long half-life, and significant environmental mobility. Resins have been demonstrated effective bifunctional properties for both the detection and separation of 99 TcO 4 ⁻ . However, the poor stability of these compounds limits their practical application. Here, a chemical grafting strategy is presented to synthesize ultra-stable plastic scintillation resin, in which 4-vinylpyridine and divinylbenzene are cross-linked as matrix polymer to withstand extreme conditions and a fluorophore “shield” to convert beta radiation into detectable signals. As expected, the as-obtained resin exhibits a high adsorption capacity of 549.2 mg g ⁻¹ for 99 TcO 4 ⁻ with a rapid kinetic response of just 10 min as well as superior selectivity at 1000 times excess of interfering ions and full reusability. Moreover, it showed remarkable stability under 800 kGy, 3.0 mol L −1 HNO 3 or 2.5 L solution continuous leaching, consistently maintaining high separation and detection efficiency after recycling 10 times. This strategy paves a new way to develop stable resin for the rapid capture and accurate measurement of 99 TcO 4 ⁻ , which owns great potential for practical application.
N , N , N ′, N ′-tetramethylmalonamide (TMMA) has been successfully grafted onto the chloroacetylated poly(styrene-co-divinylbenzene) resin to obtain a novel diamide-based resin (PS–TMMA). PS–TMMA exhibited high adsorption capacity and selectivity toward TcO 4 − in 0.1–1 M HCl. The adsorption process of PS–TMMA conforms (Revise: conformed) to Langmuir isotherm and pseudo-second-order kinetics model. The results of column experiments revealed TcO 4 − can be completely separated from the coexisting fission products (Sr(II), Eu(III), Dy(III), and 1 M NH 3 ·H 2 O can re-collect TcO 4 − absorbed in the resin column. The adsorption mechanism of TcO 4 − is considered that PS–TMMA is converted into anion exchange resin in acidic condition.
Tingwei Hu,Wenfeng Hao,Haifeng Zou,Wenjuan Xue,Donghai Mei,Yanhua Song,Wenfu Yan
Technetium-99 ( 99 Tc), as a β-emitting radionuclide, is one of the main components of nuclear waste. The fast environmental mobility of 99 TcO 4 - makes it a great threat to the environment and human beings. Although some adsorption materials have been developed to remove 99 TcO 4 - from the nuclear wastewater, the low selectivity and poor stability under acid and radiation conditions limit their actual application. In this work, an N -methylimidazolium modified macroporous anion exchange resin (PMiMCl) was developed for the highly selective removal of 99 TcO 4 - . Batch adsorption experiments demonstrated that the PMiMCl resin exhibited high adsorption capacity (Re(VII), 677.21 mg g −1 ) in a wide pH range (3–7). The resin showed high stability after acid (5 mol L -1 HCl), alkali (5 mol L -1 NaOH) and radiation (1000 KGy 60 Co γ) treatment and the remove ability was little influenced. More importantly, in the presence of high concentration of competing anions, the removal efficiency of 99 TcO 4 - with PMiMCl resin can also reach to 97.64%, which was much higher than those treated by commercial resins (93.02% for ZGANR170 and 93.10% for IRN78), demonstrating its good selectivity. The density functional theory calculations revealed that the high selectivity was attributed to the strongest interaction of imidazole cation in PMiMCl resin with 99 TcO 4 - anion compared with NO 3 − , SO 4 2− and Cl − anions. These superior features coupled with low cost and feasible for large scale production and application make PMiMCl resin great potential for 99 Tc removal in nuclear wastewater.
危险品化学品经营许可证（带存储）