CERAMICS INTERNATIONAL
·
2023
·
IF 5.2
Zhangyi Huang,Wanying Guo,Yang Shi,Ruichong Chen,Zhijun Wang,Yutong Zhang,Junjing Duan,Jianqi Qi,Haomin Wang
The Gd 2 Zr 2 O 7 (GZO)-based ceramic waste form exhibits promising potential for radioactive waste immobilization. However, the isomorphic immobilization capacity and irradiation effects of GZO-based ceramic waste forms with varying waste loads remain inadequately understood. This study employed a facile combustion method to synthesize ceramic powders and utilized conventional sintering with a relatively short dwelling time to fabricate GZO-based ceramic waste forms. We investigated the isomorphic immobilization behavior and He ion irradiation effects of the synthesized waste forms. The outcomes demonstrate that GZO effectively immobilizes simulated waste composed of 11 types of oxides, achieving a waste load as high as 50 wt% with a single pyrochlore phase and homogeneous element distribution. Under He + irradiation, aggravated structural degradations, including exacerbated lattice swelling, increased amorphization degree, and premature He bubble chain/microcrack formation, were observed in GZO-based waste forms with an increasing waste load.
研究领域:
材料科学
·
核能工程
·
放射化学
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF NUCLEAR MATERIALS
·
2020
·
IF 2.485
Guilin Wei,Xiaoyan Shu,Zhentao Zhang,Fen Luo,Yi Liu,Bingsheng Li,Yi Xie,Lan Wang,Xirui Lu
The treatment of radioactive iodine waste is particularly difficult because of its volatilization issues. In this study, amorphous silica gel was used to gradually replace crystalline SiO 2 in B 2 O 3 -Bi 2 O 3 -ZnO-SiO 2 based materials aimed to investigate the effects on iodine waste immobilization. Samples with different silica gel replacements (0, 20, 40, 60, 80, and 100%) were characterized by XRD, FT-IR, and SEM-EDS. The results showed that silica gel had a benefit in the immobilization of iodine waste at low-sintering temperatures (500, 550, and 600 °C). At 550 °C, AgI was immobilized in the pure glassy matrix and elements (Ag and I) distributed uniformly on the matrix surface. FT-IR analysis presented the tetrahedral SiO 4 units in the sintered samples that were mainly in the form of sheets. Our work revealed the potential application of silica gel in the field of iodine waste immobilization.
研究领域:
核废料管理
·
材料科学
✓ 已验证
产品关联
DOI
高影响因子
CERAMICS INTERNATIONAL
·
2020
·
IF 3.83
Zi-Jun Wei,Weichao Bao,Shi-Kuan Sun,Lewis R. Blackburn,Sheng-Heng Tan,Laura J. Gardner,Wei-Ming Guo,Fangfang Xu,Neil C. Hyatt,Hua-Tay Lin
Praseodymium-doped zirconolite ceramics targeting nominal composition Ca 1-x Pr x ZrTi 2-5x/3 Al 5x/3 O 7 (x ≤ 0.20, Δx = 0.05) were fabricated by a mixed oxide solid state reaction, at 1350 °C in air for 20 h. Praseodymium (Pr) was employed as a surrogate for neptunium (Np), with Al 3+ co-accommodated to provide charge balance. High-resolution transmission electron microscopy and electron diffraction analyses confirmed that zirconolite crystallised as the 2M monoclinic polytype throughout the phase evolution, with no evidence of transformation to other polytype structures. Phase assemblage and microstructural data were consistent with zirconolite occupying a high fraction of the phase assemblage (> ca . 93 wt.%), alongside a minor secondary perovskite phase at all levels of targeted Pr incorporation. Despite this, it was demonstrated near theoretical density formed through a solid-state fabrication route, and we therefore propose that, through analogy with the corresponding Pr solid solution, zirconolite may be a suitable candidate for the immobilisation of Np-bearing wastes.
研究领域:
材料科学
·
核废料管理
·
环境科学
✓ 已验证
产品关联
DOI
高影响因子
NUCLEAR ENGINEERING AND DESIGN
·
2024
·
IF 1.9
Shiyin Ji,Xiuhua Ji,Yanhao Song,Yanxia Wei,Tao Duan
Regulation of microstructure and processing cost of waste form are important for the design and application of high-level radioactive waste immobilization. In this study, CaZrTi 2 O 7 (zirconolite) – CaNdTiNbO 7 (pyrochlore) ceramics were synthesized via conventional sintering method at 1000–1500 °C to investigate the effect of sintering temperature on the microstructure, solidification, and crystal evolution. The powder x-ray diffraction (XRD) and backscattered scanning electron microscopy–energy dispersive spectroscopy (BSEM–EDS) results indicated gradual formation of zirconolite and pyrochlore ceramics, following with their densification when increasing sintering temperature. It was found that sintering temperature should be higher than 1300 °C to form zirconolite-pyrochlore solid solutions. Densified pyrochlore was obtained at 1500 °C. In addition, transformation from relatively low-symmetry lattice to higher-symmetry lattice was found with an increase in sintering temperature. Furthermore, higher temperature can enhance the crystal growth and densification in the ceramic composite. The finding in this study could provide important suggestions to design and process zirconolite-pyrochlore waste forms for industrial application.
研究领域:
材料科学
·
核能工程
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF NUCLEAR MATERIALS
·
2015
·
IF 1.865
Kuibao Zhang,Guanjun Wen,Dan Yin,Haibin Zhang
Synroc is recognized as the second generation waste form for the immobilization of high-level radioactive waste (HLW). Zirconolite-rich (CaZrTi 2 O 7 ) Synroc minerals were attempted by self-propagating high-temperature synthesis (SHS) using Fe 2 O 3 , CrO 3 , Ca(NO 3 ) 2 as the oxidants and Ti as the reductant . All designed reactions were ignited and sustained using Ca(NO 3 ) 2 as the oxidant, and zirconolite-rich ceramic matrices were successfully prepared with pyrochlore (Ca 2 Ti 2 O 6 ), perovskite (CaTiO 3 ) and rutile (TiO 2 ) as the minor phases. The sample CN-4, which was designed using Ca(NO 3 ) 2 as the oxidant with TiO 2 /Ti ratio of 7:9, was readily solidified with density of 4.62 g/cm 3 and Vickers hardness of 1052 HV. CeO 2 was successfully stabilized by the CN-4 sample with resultant phase constituent of 2M-CaZrTi 2 O 7 and CaTiO 3 .
研究领域:
材料科学
·
核废物管理
·
无机化学
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF SOLID STATE CHEMISTRY
·
2021
·
IF 3.498
Yaxin Feng,Guilin Wei,Yi Liu,Wenhong Han,Yan Chen,Runjie Sun,Lin Peng,Meihua Ma,Yu Zhang,Zhentao Zhang,Xirui Lu
The immobilization of iodine waste is a challenge in the field of nuclear waste . In this work, iodine waste (silver-coated silica gel with different iodine loadings) was immobilized at low-sintering temperatures (500, 550, and 600 °C). XRD represented that the crystallized phases of the sintered matrix consist of AgI and B 2 O 3 . The crystallization behavior of boron can be found as the sintering temperature increased from 500 °C to 600 °C. FT-IR results proved that in the process of crystallization, part of the microstructure related to B–O stretching transformed from [BO 4 ] to [BO 3 ] units, which benefits low-temperature iodine waste immobilization due to the bonding energy of [BO 3 ] is higher than that of [BO 4 ]. Our work reveals the B-related microstructure transition in low-temperature immobilization iodine waste.
研究领域:
核废物处理
·
材料科学
·
无机化学
·
放射化学
·
环境工程
✓ 已验证
DOI
高影响因子
ENVIRONMENTAL RESEARCH
·
2025
·
IF 7.7
Pan Tan,Jiaqin Wei,Sihong Luo,Guilin Wei,Xiaoan Li,Lijing Huang,Xirui Lu,Xiaoyan Shu
Glass matrices with high waste load capacity, stability, and economic viability holds significant technological implications for efficient and safe nuclear waste immobilization. Aluminosilicate glasses with various Si/Al molar ratios were successfully prepared by incorporating Al 2 O 3 into natural granite, effectively enabling precise regulation of the Si/Al ratios and overcoming the challenge of achieving complete vitrification. Here, we report a glass waste form with ultra-high CeO 2 loading (up to 20 wt .%) that exhibits excellent structural stability. At a Si/Al molar ratio of 3:1, cerium can incorporate into the glass network by forming Ce-O bonds through coordination with oxygen atoms in the [AlO 6 ] units. [AlO 6 ] is converted to more stable [AlO 4 ], thereby enhancing the stability of the glass. Up to 20 wt .% CeO 2 (9.62 mol%) can be fully incorporated into the glass system, where approximately 79.71 % of the bridging oxygen atoms form stable Si-O-Si and [AlO 4 ] units, contributing to a structurally robust glass network. The Ce-O bond length in the glass matrix is shorter (2.27 Å) than in CeO 2 , confirming enhanced coordination stability and aligning with superior chemical durability and mechanical properties. This work highlights the critical role of the Si/Al molar ratio and establishes low-cost granite could serve as a viable host material for nuclear waste immobilization.
研究领域:
材料科学
·
核工程
·
玻璃化学
·
废物处理
✓ 已验证
产品关联
DOI
PubMed
高影响因子
Journal of Environmental Chemical Engineering
·
2025
·
IF 7.2
Constantin Muhire,Behery Realy,Xiyan Xu,Dagang Li,Niu Zhang,Dongxiang Zhang
In this work, a novel inorganic-organic Bi/La-C-oxide material for iodine vapor capture in conditions of high temperature, mostly encountered during the reprocessing of the spent nuclear fuel, was synthesized. Bi/La-C-oxide (Bi/La=1, 300 °C) was synthesized using a new approach that allowed the non-decarbonization of used fuels, which instead made a framework with the core of Bi/La oxide to form a hybrid material, which exhibited a fast iodine uptake with a capacity of 1339.64 mg·g −1 at 18 h and 1301.47 mg·g −1 after 26 h at 200 °C, respectively. Notably, Bi/La-C-oxide (Bi/La=1, 300 °C) owed the high iodine-adsorbing ability mainly from its structure made of tetragonal units of Bi 1.92 La 0.08 O 3 linked together with esters to form a polyesterified Bi/La-C-oxide framework. The thermal stability analysis of the materials before and after iodine capture showed high thermal stabilities, proving their ability to withstand real-field high-temperature conditions. ZnO was used to consolidate the iodine wastes to avoid post-sorption secondary pollution, and the iodine leaching rate was minimized to 1.143 × 10 −3 g·(m 2 ·day) −1 after 7 days of product consistency test-A.
研究领域:
核化学
·
无机-有机杂化材料
·
放射性废物管理
·
环境修复
·
材料科学
✓ 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）