HYDROMETALLURGY
·
2019
·
IF 3.465
Zhenning Lou,Mengnan Huang,Junshuo Cui,Shuyao Wu,Shanshan Xing,Peng Zhou,Weijun Shan,Ying Xiong
Technetium ( 99 Tc), a radionuclide generated from uranium fission in nuclear reactors, has posed a major threat to humans due to its long half-life and radioactivity. Therefore, it is urgent to develop a strategy of selectively and efficiently capturing of 99 Tc. In this work, a series of solid copolymers (denoted as DVB-[C x ClVim][Cl]) were synthesized for efficient adsorption of perrhenate (ReO 4 − , a surrogate for TcO 4 − ) from mixed ions solution. The adsorbents with vinylimidazolium-based ionic liquid as functional group and divinylbenzene (DVB) as the basic framework exhibited stable structure and good ReO 4 − adsorption performance. The influences of the linear n-alkyl chain length on the morphology and adsorption property of the copolymers were discussed in detail. The maximum uptake of Re(VII) on DVB-[C 4 ClVim][Cl] was 517.61 mg·g −1 . Rhenium could be separated from molybdenum in the presence of co-anions and co-cations by DVB-[C 6 ClVim][Cl], which demonstrated its good adsorption selectivity . The kinetic studies showed that pseudo-second-order model was more suitable for describing the behavior of Re(VII) adsorption. The adsorption mechanism was ion-exchange between Cl − and ReO 4 − confirmed by FI-IR, IC and XPS analysis. Additionally, DVB-[C x ClVim][Cl] remained effective Re(VII) capture ability after eight adsorption/elution cycles, demonstrating their good reusability.
研究领域:
环境科学
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材料科学
·
放射化学
✓ 已验证
DOI
高影响因子
CHEMICAL ENGINEERING JOURNAL
·
2019
·
IF 8.355
Mu Ding,Lang Chen,Yuwei Xu,Bo Chen,Jie Ding,Rulei Wu,Chao Huang,Yi He,Yongdong Jin,Chuanqin Xia
99 Tc is a β-emitting radionuclide with high fission yield, long half-time and it is urgent to remove Tc from liquid radioactive waste due to its potential toxicity for human. Herein, we presented a viologen-based cationic organic polymer (VBCOP) as a novel adsorbent with cationic sites and functional groups for efficient capture of Re/Tc(VII, IV) from aqueous medium. The results showed that this material could rapidly remove TcO 4 − /ReO 4 − from aqueous solution within 5 min and the maximum sorption capacity for Re(VII) could reach up to 444 mg g −1 , and the distribution coefficient ( K d ) towards Re(VII) and Tc(VII) reached 4.0 × 10 5 and 7.2 × 10 5 mL g −1 , respectively. And more, the adsorption mechanism was also studied by X-ray photoelectron spectroscopy (XPS), Energy dispersive spectrometer (EDS) mapping and Ion chromatography (IC), the results suggested an ion-exchange process in which the Cl − in this material was replaced by ReO 4 − . Additionally, we investigated its adsorption mechanism towards low-valent Re which was prepared by reducing ReO 4 − with NaBH 4 , and the flexible tetraaza macrocycle introduced in the material chelated with Re(IV) was confirmed by X-ray photoelectron spectroscopy (XPS) and Extended X-ray absorption fine structure (EXAFS) analysis. In general, the research exhibits a new sorbent material that can remove both TcO 4 − /ReO 4 − and the low-valent Tc/Re, and provide a new strategy to treat radioactive waste containing Tc with different valences.
研究领域:
放射化学
·
环境科学
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF ANALYTICAL ATOMIC SPECTROMETRY
·
2019
·Vol. 34
·期 11
·2229-2235
·
IF 3.646
Lei Tang,Wenting Bu,Xuemei Liu,Sheng Hu
The accurate determination of ultra-trace amounts of 99Tc is still a challenge due to its long half-life and the lack of a commercially available isotopic tracer. Negative thermal ionization mass spectrometry (N-TIMS) has been proven to be a powerful method for the analysis of isotopes with relatively high ionization potentials. In this work, we established a novel method based on N-TIMS for the measurement of Tc isotopes. By using Pt filaments and Ba(OH)2 as the ionization activator, the ionization efficiency of Tc was significantly improved to be more than 10%. The oxygen isotopic compositions were measured with a 99Tc standard solution and the obtained coefficients can be applied directly for the correction of interferences from oxygen isotopes. We used this method for the measurement of the isotopic abundance and concentration of the 97Tc tracer produced in our laboratory. Due to the high ionization efficiency of this method and the calibration of the 97Tc tracer, ultra-trace determination of 99Tc in radioactive wastes and environmental samples is now possible.
研究领域:
分析化学
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环境科学
·
放射化学
✓ 已验证
产品关联
DOI
高影响因子
NUCLEAR ENGINEERING AND DESIGN
·
2024
·
IF 1.9
Chenchen Niu,Aiqing Chen,Kaiwen Hu,Kai Xu
Due to its long half-life, high fission yield, and high mobility in the groundwater, Technetium-99 (Tc-99) is a troublesome nuclide in nuclear waste. Moreover, the primary concern is the high volatility of Tc during nuclear waste vitrification. Previous studies demonstrated that nitrate significantly affected the Tc volatilization during the vitrification of Tc-containing waste. However, identifying how nitrate affects Tc volatilization is challenging due to the complexity of the composition of nuclear waste. This study used a simplified SiO 2 -KNO 3 -KReO 4 feed with rhenium (Re) as a Tc non-radioactive surrogate to study the nitrate effect on the Re volatilization at elevated temperatures. The results showed that KNO 3 could facilitate Re volatilization at temperatures below 800 °C when the molar percentage of KNO 3 in the KNO 3 -KReO 4 binary system exceeded 60 mol%, which was attributed to the eutectic reaction between KReO 4 and KNO 3 at 310 °C. However, the increased KNO 3 content could inhibit the Re volatilization at temperature above 1200 °C since adding KNO 3 could increase the amorphous phase content, where Re was encapsulated and hardly evaporated.
研究领域:
核化学
·
环境科学
✓ 已验证
产品关联
DOI
高影响因子
ENVIRONMENTAL SCIENCE & TECHNOLOGY
·
2024
·
IF 10.8
Yanyan Chen,Hao Deng,Pengliang Liang,Heng Yang,Long Jiang,Jing Yin,Jia Liu,Shuying Shi,Huiqiang Liu,Yuxiang Li,Ying Xiong
Sustainable photocatalysis can effectively reduce the radioactive 99TcO4– to less soluble TcO2·nH2O(s), but the reduction efficiency is highly susceptible to coexisting nitrate (NO3–). Here, we quantitatively investigate photocatalytic remediation conditions for Tc-contaminated water stimulated by the analogue perrhenate (ReO4–) in the presence of NO3–, and we elucidate the influence mechanism of NO3– by in situ characterizations. The interfering NO3– can compete with Re(VII) for the carbonyl radical (·CO2–) produced by formic acid (HCOOH) oxidation to generate nitrogen-containing products such as NH4+, NO2–, and NOx, resulting in the decrease in the Re(VII) reduction ratio. Under the conditions of 4% (volume ratio) HCOOH and pH = 3, the yield of NOx is the lowest, and the selectivity of N2 reaches 93%, which makes the overall reaction more in line with the pollution-free concept. The X-ray absorption fine structure reveals that the redox product Re(IV) mainly exists in the form of ReO2·nH2O(s) and is accompanied by a decrease with the increase in NO3– concentration. Re(VII)/Tc(VII) reduction suffers from a serious interferential effect of NO3–, whereas the higher the concentration of NO3–, the more conducive to slowing down the reoxidation of the reduction products, which is advantageous for the subsequent sequestration or separation.
研究领域:
环境科学
·
放射化学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
Advanced Science
·
2024
·
IF 14.3
Tonghuan Liu,Yichen Hu,Junqiang Yang,Kesheng Hu,Bei Qi,Yun Zhou,Juan Tong,Man Wang,Liang Huang,Keliang Shi,Xiaolin Hou
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.
研究领域:
环境科学
·
核化学
·
材料科学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
JOURNAL OF RADIOANALYTICAL AND NUCLEAR CHEMISTRY
·
2021
·Vol. 328
·期 1
·481-490
·
IF 1.371
Fu Lingxiao,Pan Xiaohan,Zu Jianhua,He Linfeng
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.
研究领域:
化学工程
·
核化学与放射化学
✓ 已验证
产品关联
DOI
高影响因子
ENVIRONMENTAL SCIENCE & TECHNOLOGY
·
2019
·
IF 7.149
Hao Deng,Zi-jie Li,Xu-cong Wang,Lin Wang,Kang Liu,Li-yong Yuan,Zhi-yuan Chang,John K. Gibson,Li-rong Zheng,Zhi-fang Chai,Wei-qun Shi
The pertechnetate anion (99TcO4–) is a long-lived radioactive species that is soluble in aqueous solution, in contrast to sparingly soluble 99TcO2. Results are reported for photocatalytic reduction and removal of perrhenate (ReO4–), a nonradioactive surrogate for 99TcO4–, using a TiO2 (P25) nanoparticle suspension in formic acid under UV–visible irradiation. Re(VII) removal up to 98% was achieved at pH = 3 under air or N2. The proposed mechanism is Re(VII)/Re(IV) reduction mediated by reducing radicals (·CO2–) from oxidation of formic acid, not direct reduction by photogenerated electrons of TiO2. Recycling results indicate that photocatalytic reduction of ReO4– exhibits excellent regeneration and high activity with >95% removal even after five cycles. 99Tc(VII) is more easily reduced than Re(VII) in the presence of NO3– with very slow redissolution of reduced 99Tc. This study presents a novel method for the removal of ReO4–/99TcO4– from aqueous solution, with potential application for deep geological disposal.
研究领域:
环境科学
·
放射化学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
ACS Applied Materials & Interfaces
·
2025
·
IF 8.2
Juan Tong,Yuankun Liu,Lipeng Han,Binliang Li,Beijia Chang,Xiaoqing Gao,Tonghuan Liu,Junqiang Yang,Keliang Shi,Xiaolin Hou
Due to the complex type of coexisting ions, remarkable acidity, and high radioactivity, efficient and sustainable methods for the removal of pertechnetate (99TcO4–) from acidic nuclear waste streams have attracted much attention. Herein, a porous highly polymeric zwitterionic resin (PDVBVIM1.5SO3) was synthesized by installing sulfobetaine zwitterionic units in the polymeric imidazole resin to achieve the purpose of balancing the hydrophilicity and hydrophobicity of the resin structure and improving the reaction kinetics and ion selectivity of the resin at the same time for perrhenate (ReO4–)/99TcO4– removal from acidic solutions. The results demonstrate that PDVBVIM1.5SO3 exhibits fast adsorption kinetics, superior adsorption capacity, and excellent selectivity in the presence of a variety of 1000-fold competing anions. The rapid elimination of ReO4– can be achieved even in 1 mol L–1 HNO3. Importantly, when subject to acid soaking, calcination procedure, and high doses of ionizing radiation, PDVBVIM1.5SO3 maintained its structural integrity and outstanding performance. Additionally, PDVBVIM1.5SO3 displayed outstanding adsorption efficiency toward a simulated Hanford low-activity waste stream with ReO4–. This work demonstrates that achieving a balance between hydrophobicity and hydrophilicity in an exchange resin is of great significance for enhancing the selection and removal of TcO4–/ReO4–, and PDVBVIM1.5SO3 resin could be an excellent acid nuclear waste-adsorbing material candidate.
研究领域:
化学工程
·
环境科学
·
核科学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
ENVIRONMENTAL POLLUTION
·
2024
·
IF 7.6
Miaomiao He,Yuxuan Chen,Guangyuan Chen,Wenhao Li,Mingxing Zhang,Chao Zhang,Hao Zhang,Xingyi Long,Kui Tang,Tao Duan,Lin Zhu
The extraction of 99 TcO 4 − from radioactive effluents is extremely crucial for the purposes of nuclear disposal and environmental remediation. Herein, utilizing a facile and low-cost synthesis method, we report a pyridinium-based cationic polymer network , CPP-Cl, with impressive adsorption performance and ultrafast adsorption kinetics towards ReO 4 − . The structure featuring highly density of charged pyridinium units was synthesized, making it an effective adsorbent for capturing ReO 4 − . The material showed fast ReO 4 − adsorption kinetics reaching adsorption equilibrium within 30 s, an excellent capture capability of 1069.7 mg/g, and exceptional separation efficiency of 94.3% for removing 1000 ppm ReO 4 − . Furthermore, it possessed excellent reusability in multiple sorption/desorption trials and good uptake capacity within a widely ranging pH values. It is noteworthy that the extraction efficiency of CPP-Cl for ReO 4 − from simulated nuclear waste can be up to 94.2%. The favorable performance of the material in multiple tests revealed that CPP-Cl has tremendous potential as a high-efficiency sorbent for capturing 99 TcO 4 − /ReO 4 − in complex nuclear associated environmental systems.
研究领域:
环境科学
·
核化学
·
材料科学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
CHEMICAL ENGINEERING JOURNAL
·
2023
·
IF 15.1
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.
研究领域:
核化学
·
环境科学
·
材料科学
✓ 已验证
产品关联
DOI
高影响因子
Science China-Chemistry
·
2025
·
IF 9.7
Li Jie,Zhao Yuting,Li Baoyu,Chen Lixi,Guo Qi,Song Wanrong,He Linwei,Chen Long,Zhang Mingxing,Chai Zhifang,Wang Shuao
Efficient segregation of TcO 4 − from high-level radioactive wastes (HLW) is critical for robust nuclear waste management and environmental protection. However, achieving deep decontamination is especially challenging in complex conditions of strong basicity, high radiation, and excessively competitive anions. Herein, we addressed the long-term challenge by modifying the imidazolium core with phenyl, trimethylphenyl, and benzyl groups in a flexible polymer chain, which constructs a precisely targeted microenvironment for selective TcO 4 − capture. This custom-engineered material (SCU-CPN-7) exhibits fast kinetics, high adsorption capacity (314.7 mg/g), excellent distribution coefficient (1.3 × 10 7 mL/g), and remarkable efficiency in TcO 4 − uptake under the combining extreme conditions of strong alkalinity (1 M NaOH) and high radioactivity. More importantly, owing to the synergistic effects of the hydrophobic effect, electrostatic affinity, and p- π interactions, SCU-CPN-7 demonstrates exceptional selectivity, capable of almost quantificationally removing TcO 4 − in the coexistence of a large excess of NO 3 − and SO 4 2− , leading to an unparalleled uptake performance of TcO 4 − from simulated HLW in both batch and dynamic column separation tests.
研究领域:
环境科学
·
核化学与放射化学
✓ 已验证
产品关联
DOI
高影响因子
危险品化学品经营许可证（带存储）