SEPARATION AND PURIFICATION TECHNOLOGY
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2024
·
IF 8.1
Wenqi Liu,Jingyan Zhang,Mei Dong,Zhaoyi Ding,Qunfei Wang,Fanghao Ning,Qin He,Yanyan Chen,Zhen Zhao,Zhongfu Li,Conghua Liu
Low-silica chabazite (CHA) catalysts with varying configurations of Cu 2+ -2Z and [Cu(OH)] + -Z active centers are developed through the regulation of the opening of CHA-cages. The catalysts are subsequently applied to the selective catalytic reduction of NO x by NH 3 (NH 3 -SCR) reactions. A series of characterizations and performance evaluations indicate that the density of [Cu(OH)] + -Z in eight-member rings (8MRs) is positively correlated with low-temperature performance. Moreover, the presence of partial Cu 2+ -2Z in six-member rings (6MRs) enhances activity and tolerance at high temperatures. The residual K + ions in the CHA-cages after NH 4 + exchange are retained in the 6MRs. Density functional theory calculations demonstrate that the residual K + ions stabilize the 6MRs structure, ensuring the entry and stable presence of the active Cu 2+ -2Z centers. In situ analysis reveals the reaction intermediates involved in the NH 3 -SCR process on representative catalysts. These findings can further elucidate the active centers of CHA-type catalysts and guide the design of commercial catalysts.
研究领域:
催化化学
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环境科学
✓ 已验证
产品关联
DOI
高影响因子
SEPARATION AND PURIFICATION TECHNOLOGY
·
2025
·
IF 9
Junyi Feng,Yuqi Jiang,Kaifa Du,Wei Li,Huayi Yin,Bowen Deng,Dihua Wang
Capturing and solidifying the fission elements in radioactive waste salt is an urgent task for the safe treatment and final disposal of spent fuels. In this paper, we present a synergistic method that combines low-temperature solution-based precursor preparation with high-temperature solid-phase sintering to synthesize sodalite while simultaneously solidifying radioactive waste salts in situ using kaolinite, a clay mineral that is economically viable and widely available. Various material characterization methods were employed to elucidate the mechanism of sodalite’s solidification of fission elements. The results demonstrated that a sodalite solidified body with strong thermal stability and high mechanical strength could be achieved when the precursor was sintered at 800℃ for 2 h. Normalized leaching rate experiments indicated that the solidification effect of sodalite on Cs, Sr, Ba, and Ce was significant, with the normalized leaching rate remaining well below 5 × 10 -4 g·cm −2 ·d -1 after 28 days. Furthermore, the solidification of these four fission elements by sodalite involves mechanisms such as ion exchange, lattice solidification, coordination chelation, and physical and chemical adsorption. In summary, the sodalite synthesized by this method exhibited excellent curing performance without the need for additional sintering agents or secondary glass coatings. The findings of this study will serve as a valuable reference for the final disposal of irradiated nuclear fuels.
研究领域:
材料科学
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核能工程
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环境科学
✓ 已验证
产品关联
DOI
高影响因子
ACS Applied Materials & Interfaces
·
2022
·
IF 10.383
Ruiqi Wang,Fei Liang,Xin Liu,Yi Xiao,Qianqian Liu,Xian Zhang,Li-Ming Wu,Ling Chen,Fuqiang Huang
The achievement of balanced performance with a strong second-harmonic generation (SHG) response, proper birefringence, and wide band gap concurrently is a crucial but challenging task in infrared nonlinear optical (IR-NLO) crystals. Here, we theoretically confirmed that the heteroanionic oxysulfide tetrahedron would produce improved polarizability anisotropy and quadratic hyperpolarizability compared with the monoanionic oxide or sulfide tetrahedra. When this anion-mixing strategy was applied, melilite oxysulfide with the four representative members A2GeGa2OS6 (A = Ca, Sr) and Sr2MGe2OS6 (M = Zn, Cd) was successfully discovered as a promising IR-NLO material system. Remarkably, compared with the monoanionic melilite oxides, these compounds exhibited unbiased performances of proper birefringences (0.106–0.143), strong SHG responses (>10× melilite oxide Ba2CdGe2O7, 1.3–2.1× AgGaS2 (AGS) @1570 nm) with phase-matchable ability, wide band gaps (2.95–3.15 eV), and large laser-induced damage thresholds (LIDTs, 5.6–13.4× AGS). The high structure tolerance of melilite offers a great possibility to improve the SHG response via tuning the orbital composition and hybridization near band edges. This work provides an effective approach for the design of high-performance IR-NLO materials.
研究领域:
材料科学
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光学
·
化学
✓ 已验证
DOI
高影响因子
JOURNAL OF RADIOANALYTICAL AND NUCLEAR CHEMISTRY
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2022
·Vol. 331
·期 7
·2919-2928
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IF 1.754
Jiang Yuqi,Gao Shuaibo,Li Peng,Ma Yongsong,Yin Huayi,Wang Dihua
The waste LiCl–Li 2 O oxide reduction salt was solidified and transformed into sodalite by the spark plasma sintering method. Compared with traditional solidification method, SPS operates at a lower pressure, lower temperature, shorter processing time, and without sintering additive. The SPS-solidified sodalite presents a low porosity of 0.37% and low leaching rates of 2.21 g m –2 d –1 for Cs, 3.05 × 10 –1 g m –2 d –1 for Ba, and 3.12 × 10 –1 g m –2 d –1 for Sr. Overall, the SPS is a promising method to solidify various waste OR salts.
研究领域:
材料科学
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核废料管理
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF HAZARDOUS MATERIALS
·
2025
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IF 11.3
Qian Zheng,Ziwei Wang,Zhouyang Tian,Lin Cai,Chengfeng Jiang,Lili Deng,Dazhong Yang,Zhenhua Wei
The development of cost-effective point-of-use (POU) devices that effectively remove lead (Pb) from drinking water is imperative in mitigating the threat of Pb contamination to public health in underdeveloped regions. Herein, we have successfully transformed inexpensive natural kaolinite as hydroxy-sodalite (HySOD) via a simple hydrothermal process, achieving an impressive yield of 91.5 %. Remarkably, HySOD demonstrates excellent selectivity and affinity towards Pb 2+ with an adsorption capacity of 476 mg/g in a single Pb 2+ system and a high distribution coefficient of 5.0 × 10 7 mL/g in multi-cations system, several orders of magnitude higher than other cations, showing remarkable Pb 2+ removal efficiency. Mechanism studies reveal that the preeminent Pb 2+ capture capacity of HySOD is mainly attributed to the fast surface chemisorption effects and spontaneous phase change from Na 8 Al 6 Si 6 O 24 (OH) 2 ·2H 2 O to Pb 4 Al 6 Si 6 O 24 (OH) 2 ·5H 2 O caused by cation exchange effects. Through a continuous filtration test, a simplified HySOD-loaded POU device is employed to treat Pb-contaminated water with the Pb 2+ concentration of 200 μg/L. At a high water flux of 477 L/m 2 /h, the Pb 2+ effluent concentration is swiftly reduced below 10 μg/L, well meeting the security standard for drinking water. Overall, this work introduces a remarkable Pb 2+ removal material, showing significant application potential for POU drinking water purification.
研究领域:
环境科学
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材料科学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
Journal of Advanced Ceramics
·
2022
·Vol. 11
·期 10
·1613-1625
·
IF 11.534
Zhang Yuan,Zhao Longfei,Ye Zhupeng,Zeng Yanwei
Starting with the stoichiometric and highly homogeneous gel-precursor, single-phase metastable melilite La 2 Ga 3 O 7.5 , as the end-member of solid solution La 1+ x Sr 1− x Ga 3 O 7+ x /2 (0≼ x ≼1), has been synthesized by solid-state reaction at 700 °C for 2 h via a kinetically favorable mechanism and characterized by X-ray diffraction (XRD), Raman, X-ray photoelectron spectroscopy (XPS), field emission scanning electron microscopy (FESEM), transmission electron microscopy (TEM), AC impedance spectroscopy, etc. It has been revealed that the as-synthesized melilite La 2 Ga 3 O 7.5 shows an orthorhombic symmetry with crystal cell parameters a = 11.4690(1) Å, b = 11.2825(4) Å, and c = 10.3735(4) Å, while has more Raman active modes than LaSrGa 3 O 7 with a tetragonal structure, which was also synthesized under the same conditions for comparison, but tends to slowly decompose into perovskite LaGaO 3 and Ga 2 O 3 when annealed at 700 °C for over 20 h driven by its meta-stability. Moreover, the metastable La 2 Ga 3 O 7.5 shows a higher XPS binding energy for the excess oxide ions in the crystal structure than those at normal lattice sites. Its intrinsic grain oxide ion conductivity can reach as high as 0.04 and 0.51 mS·cm −1 at 550 and 700 °C, respectively, characterized by a simple Arrhenius relationship ln( σT )—1/ T with invariable activation energy, E a = 1.22 eV, over the temperature range from 300 to 700 °C, along with an apparent grain boundary conductivity that is about double that from the grains thanks to the clean grain boundaries. This paper provides a new strategic approach to the synthesis of complex oxides that may be of high performance but are difficultly achieved by the conventional ceramic method at high temperatures.
研究领域:
材料科学
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固体化学
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电化学
✓ 已验证
产品关联
DOI
高影响因子
Scientific Reports
·
2020
·Vol. 10
·期 1
·1-9
·
IF 3.998
Chen Xutao,Yu Lisha,Zou Shihui,Xiao Liping,Fan Jie
It is challenging to develop a low-cost household water treatment (HWT) that simultaneously deliver an effective and robust way for safe and reliable water supply. Here, we report a simple flow-through filter made by zeolite-cotton packing in a tube (ZCT) as low-cost HWT device to remove heavy metal ions from contaminated water. The zeolite-cotton is fabricated by an on-site template-free growth route that tightly binds mesoporous single-crystal chabazite zeolite onto the surface of cotton fibers. As a result, the ZCT set-up with optimized diameter achieves both high adsorption efficiency, proper flow rate, reliable supply and strong stability at the same time. After flowed through the set up packed with 10 g of zeolite-cotton, 65 mL 1000 ppm Cu 2+ solution was purified down to its safety limit (<1 ppm). Notably, their efficiency remains unaltered when filtering several ions simultaneously. In a simulated purification process, 8 L of water contaminated by Cu 2+ , Cd 2+ and Pb 2+ could be transformed into drinking water and it enables the removal of heavy metals to concentrations of below 5 ppb (μg L −1 ). We also show that the ZCT can be used for disinfection by introducing Ag-exchanged zeolite-cotton without contaminating the water with Ag ions (<0.05 ppm).
研究领域:
环境科学
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水处理
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材料科学
·
化学工程
✓ 已验证
产品关联
DOI
PubMed
高影响因子
危险品化学品经营许可证（带存储）