DESALINATION
·
2024
·
IF 8.3
Shuaiyu Zheng,Shuhui Li,Xinyu Luo,Jianwei Bai,Feixiang Gao,Huijun Yan,Maokui Li,Long Huo,Chunhong Zhang,Jun Wang
Uranium extraction from seawater is considered to be one of the seven separation technologies that will revolutionize the world. Although adsorbents containing amidoxime (AO) groups have shown promising results, their capacity and selectivity still pose challenges. In this study, polyamidoxime-graphene oxide/polyacrylamide (PAO-GO/PAM) photothermal composite hydrogels were prepared using an ultraviolet photoinitiation strategy. The three-dimensional (3D) hydrophilic network at the molecular level by radical polymerization of acrylamide retains a large amount of PAO, facilitating the easy migration of uranyl ions (UO 2 2+ ) to the interior of the adsorbent to chelate with AO groups. In addition, GO was introduced to provide the hydrogel with excellent photothermal conversion ability, causing a rapid temperature increase upon exposure to simulated sunlight. Based on the heat-absorbing properties of UO 2 2+ chelated with AO groups, the temperature increase of the hydrogel inevitably leads to a right-shift of the thermodynamic equilibrium, providing the prepared hydrogel with a high adsorption capacity under light conditions. Adsorption experiments showed that the PAO 50 -GO 1.5 /PAM hydrogel achieves a maximum adsorption capacity of 396.82 mg·g −1 at pH = 6 with an improvement of 63.4 % in the K U /K V ratio. After five cycles, the elution rate remained at 87.1 %. These results demonstrate the promising applications of the adsorbent in large-scale uranium extraction from seawater.
研究领域:
材料科学
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环境科学
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产品关联
DOI
高影响因子
CHEMICAL ENGINEERING JOURNAL
·
2024
·
IF 13.3
Fuan Lei,Yun Zhou,Long Geng,Binliang Li,Junxian Chen,Yuankun Liu,Yichen Hu,Tonghuan Liu,Keliang Shi,Wangsuo Wu,Junqiang Yang
Efficient removal of uranium from radioactive wastewater is paramount for the sustainable development of nuclear energy. However, the exploitation of superior adsorbents with practical applications remains a challenge. In this work, we engineered and synthesized an adsorbent (TPEAC) enriched with phosphine-oxime, featuring a matrix composed of hydrophilic modified amidoxime functional groups. TPEAC exhibited exceptional selectivity (Multiple ion coexistence R% > 99 %) and efficiency in uranium adsorption, with a higher adsorption rate (reach equilibrium around 400 mins) and capacity (243.9 mg/g) than raw-amidoxime (133.3 mg/g) and modified-amidoxime (175.4 mg/g) materials. Moreover, it maintained robust stability and reusability even after six adsorption–desorption cycles, with removal ratio still above 95 %. In-depth mechanistic investigations through DFT and XPS elucidated that P-O (P=O) groups exhibited a stronger affinity for U(VI) compared to other functional groups, and the adsorption of TPEAC towards U(VI) primarily due to the synergistic interaction among P-O (P=O) groups, C(NH 2 ) = N-OH, and carboxyl groups, which significantly facilitated the effective removal of U(VI). Most prominently, TPEAC performed considerable potential in processing actual uranium mine wastewater, with its dynamic column device achieving a U(VI) recovery up to 99.6 %. This work not only furnishes an efficacious and economical solution for uranium wastewater treatment but also provides new approaches for scalable application uranium materials.
研究领域:
环境科学
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材料科学
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产品关联
DOI
高影响因子
Science China-Chemistry
·
2024
·
IF 10.4
Zhang Luzhi,Huang Hongfei,Sun Lijie,Ma Xiaopeng,Tan Hui,You Zhengwei
Sequence regulation provides an effective approach to controlling the properties of polymer materials. However, this approach remains an open question in the field of dynamic polymers, which emerge as more and more important new generation materials. Herein, we systematically investigate the effect of sequence control of dynamic covalent units in tuning the properties of materials. Different sequence-controlled poly(oxime-urethanes) are designed. The dynamic oxime-urethane groups are relatively dispersed (SCP-1) or concentrated (SCP-2) distributed in their molecular chains. The sequence control strategy provides an efficient way to decouple the mechanical and self-healing performance of polymers, which is one of the most pressing challenges in the field. The relatively dispersed oxime-urethane groups in SCP-1 not only facilitate the reorganization of the dynamic covalent bonds but also increase the probability of the reformation of hydrogen bonds. The reversible dissociation/reassociation of dynamic bonds is conducive to dissipating energy to enhance mechanical performance and promote self-healing properties. As a result, SCP-1 exhibits much faster self-healing than SCP-2, and its tensile strength is nearly twice that of SCP-2. In addition, energy dissipation capacity and degradation behavior also show significant sequence dependence. Overall, this work reveals a new molecular structure-property relationship and provides a powerful strategy to construct high-performance polymers.
研究领域:
材料科学
·
高分子化学
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产品关联
DOI
高影响因子
SEPARATION AND PURIFICATION TECHNOLOGY
·
2025
·
IF 9
Zia Ahmad,Faheem Jan,Yun Li,Haitao Shi,Zarfashan Shahid,Jiajia Yang,Junyu Peng,Ningbo Geng,Waqas Niaz,Maojun Jiang,Haijun Zhang,Jiping Chen,Yanqiang Huang
Efficient uranium extraction from seawater is crucial for sustainable nuclear energy and environmental protection. Designing adsorbents with bifunctional groups that act synergistically for uranium extraction is highly desirable. Herein, leveraging the high uranyl affinity of amidoxime and the modifiable, hydrophilic nature of ethyleneimine groups, we developed a graphene oxide (GO)–based bifunctional hydrogel decorated with a 3D function-oriented network of poly(amidoxime)–poly(ethyleneimine) (PPGA@GO–H), immobilized via a simple supramolecular and covalent cross–linking approach. Detailed characterization showed excellent hydrophilicity and uniform distribution of bifunctional network, enabling PPGA@GO–H achieving high adsorption capacity of 956.1 mg g −1 and uranium selectivity of 33.35 mg g −1 , three times higher than vanadium (10.96 mg g −1 ) in simulated seawater. Meanwhile, PPGA@GO-H also maintained good performance in high levels of natural organic matter and coexisting anions (NO 3 − , Cl − , HCO 3 − , I − , and SO 4 2− ). XPS and FTIR analysis confirmed uranyl coordination with amidoxime, amine, and carboxyl groups. Moreover, DFT calculations revealed synergistically strong electron donation from amidoxime and amines to uranium, resulting in stable complexes of the lowest E binding − 8.913 eV. The hydrogel retained 85 % of its adsorption capacity after five cycles and achieved 83.9–95.1 % uranyl capturing efficiency (83.9 – 95.1 %) in real seawater. These results demonstrate that PPGA@GO-H provides new insights for designing novel materials with addressing the limitations of conventional PAO-based adsorbents in uranium extraction applications.
研究领域:
材料科学
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环境科学
✓ 已验证
产品关联
DOI
高影响因子
Journal of Cleaner Production
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2018
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IF 5.651
Shuting Zhuang,Rong Cheng,Mi Kang,Jianlong Wang
Uranium is used to make nuclear fuels for power generation . Uranium-containing wastewater is produced from fuel fabrication, fuel reprocessing , which resulted in the soil and water pollution . In this study, a cleaner and environmental friendly adsorption material, chitosan, was used to remove uranium from aqueous solution. Magnetic amidoxime functionalized chitosan beads were synthesized, characterized and applied for adsorption of uranium. The adsorption capacity of 117.65 mg/g was achieved at pH = 6, mainly due to coordination ability of amidoxime groups. With an Ms of 21.7 emu/g, the magnetic adsorbents could be fast separated from aqueous solution by the magnetic field. Additionally, the results showed that the adsorption process could be well described by the pseudo-second order kinetic (R 2 = 0.9842) and Langmuir models (R 2 = 0.9995). Finally, an adsorption mechanism was tentatively proposed to explain the adsorption process.
研究领域:
环境科学
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材料科学
✓ 已验证
产品关联
DOI
高影响因子
FOOD CHEMISTRY
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2017
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IF 4.529
Le-Le Shao,Jie Xu,Mei-Jia Shi,Xiao-Ling Wang,Yin-Ting Li,Li-Min Kong,Robert C Hider,Tao Zhou
In order to improve the antioxidant and antimicrobial abilities, hydroxamated degraded polysaccharides from Enteromorpha prolifera (HCDPE) were prepared from the corresponding carboxymethylated degraded polysaccharides (CDPE). HCDPE was characterized by FT-IR. The weight-average molecular weight of HCDPE was determined as 55.4 kDa. The in vitro antioxidant activity of HCDPE was evaluated by determining the radical (1,1-diphenyl-2-picrylhydrazyl (DPPH), hydroxyl and superoxide anion radicals) scavenging abilities and total antioxidant activity. It was found that DPPH radical scavenging ability and total antioxidant activity of HCDPE were significantly improved compared to those of CDPE. The inhibitory effects of polysaccharides against the five bacterial strains ( Bacillus subtilis , Staphylococcus aureus , Escherichia coli , Pseudomonas aeruginosa , Salmonella spp.) were also evaluated by bacterial inhibition zone and minimum inhibitory concentration (MIC) assays. The results indicated that CDPE and HCDPE possess marked antimicrobial ability, while such an effect was not observed for the crude polysaccharides (PE) and the degraded polysaccharides (DPE).
研究领域:
海洋生物学
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食品科学
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药学
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产品关联
DOI
PubMed
高影响因子
Materials
·
2018
·Vol. 11
·期 5
·790
·
IF 2.467
Huihui Xu,Zihou Liu,Qingyang Liu,Yiling Bei,Qingzeng Zhu
α-Amine ketoximesilanes are proven to be effective crosslinkers in the preparation of ketone-oxime one-component room temperature vulcanized (RTV) silicone rubber without the use of toxic metal catalyst. This work aimed to investigate the hydrolysis kinetic of α-amine ketoximesilanes, which is vitally important for the preparation of RTV silicone rubber. Five kinds of α-amine ketoximesilanes, namely α-(N,N-diethyl)aminomethyltri(methylethylketoxime)silane (DEMOS), α-(N,N-di-n-butyl)aminomethyltri(methylethylketoxime)silane (DBMOS), α-(N-n-butyl)aminomethyltri(methylethylketoxime)silane (n-BMOS), α-(N-cyclohexyl)aminomethyltri(methylethylketoxime)silane (CMOS) and α-(β-aminomethyl)aminomethyltri(methylethylketoxime)silane (AEMOS), were successfully obtained and confirmed using Fourier transform infrared spectrometer (FT-IR) and hydrogen-1 nuclear magnetic resonance (1H NMR). Kinetics of hydrolysis reactions were measured by FT-IR and conductivity. Our results illustrated that the kinetic constant rates ranged from 12.2 × 10−4s−1to 7.6 × 10−4s−1, with the decreasing order of DEMOS > n-BMOS > DBMOS > CMOS > AEMOS at the given temperature and humidity. Better performances of thermal stability could be achieved when using the α-amine ketoximesilanes as crosslinkers in the preparation of RTV silicon rubber than that of RTV silicone rubber with the use of methyltri(methylethylketoxime)silane (MOS) as a crosslinker and organic tin as a catalyst.Keywords:α-amine ketoximesilanes;hydrolysis reaction;self-crosslinkers;RTV silicone rubber
研究领域:
材料科学
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化学工程
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产品关联
DOI
PubMed
高影响因子
THERMOCHIMICA ACTA
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2015
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IF 2.184
Gui-bin Lu,Cai-xing Zhang,Wang-hua Chen,Li-ping Chen,Yi-shan Zhou
Kinetic study and thermal hazards analysis on the thermal decomposition of salicyl hydroxamic acid (SHA) was carried out using differential scanning calorimetry (DSC). The isothermal and dynamic differential scanning calorimetric curves were recorded, respectively. The temperature dependence of the observed induction periods suggests an autocatalytic decomposition mechanism, which was supported by the conversion-reduced time plots. The differential and integral isoconversional methods were used to obtain the kinetic parameters. The decomposition mechanism model of the first peak was f ( α ) = α 1.49 (1 − α ) 1.59 . Moreover, the isothermal temperature induction period were studied to obtain the activation energy, which was close to that obtained by the isoconversional integral method. The adiabatic accelerating calorimetry (ARC) was also employed to evaluate the thermal hazards. The adiabatic activation parameters were also obtained based on the autocatalytic reaction model.
研究领域:
化学动力学
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热分析
·
安全科学
✓ 已验证
DOI
高影响因子
FLUID PHASE EQUILIBRIA
·
2016
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IF 1.846
Gan bing Yao,Zhan xiang Xia,Zhi hui Li,Chao Shao
The solid–liquid equilibrium (SLE) for ternary system of caprolactam + cyclohexanone oxime + methyl tert-butyl ether were determined at three temperatures of (278.15, 293.15 and 308.15) K under pressure of 101.2 kPa. Three isothermal phase diagrams of the system were constructed based on the measured mutual solubility data. There were two pure solids formed in the ternary phase diagram , including pure caprolactam and pure cyclohexanone oxime, which were identified by the method of Schreinemakers' wet residue. At each temperature, the phase diagram contained three crystallization regions (which corresponded to caprolactam, cyclohexanone oxime, and a mixture of caprolactam and cyclohexanone oxime), two crystallization curves, and one co-saturated point. The crystallization field of caprolactam was larger than that of cyclohexanone oxime. The NRTL model was employed to correlate and calculate the ternary phase diagram. The calculated ternary phase diagram with the NRTL model agreed well with the experimental ones. The solid–liquid phase equilibrium and phase diagram for the ternary system of caprolactam + cyclohexanone oxime + methyl tert-butyl ether could provide basis for the purification process of caprolactam.
研究领域:
化学工程
·
材料科学
✓ 已验证
产品关联
DOI
高影响因子
APPLIED SURFACE SCIENCE
·
2022
·
IF 7.392
Menghan Qin,Yumiao Shi,Dingkun Lu,Jingjing Deng,Guoyue Shi,Tianshu Zhou
Due to the excessive use, cephalosporin antibiotics have been detected in various aquatic environments, which may result in environmental and health concern. In this study, bimetallic metal–organic frameworks (MOFs), Hf-UiO-66 and Ti-UiO-66, were successfully designed and obtained via post-synthetic method from UiO-66 for the adsorption of cefoperazone. A serious of adsorption experiments were investigated. The adsorption kinetics and isotherms demonstrated that the adsorption process followed pseudo-second-order kinetic model and Langmuir isotherm model. Hf/Ti-UiO-66 exhibited much better adsorption performance than the undoped UiO-66. Particularly, Hf-UiO-66 had the highest adsorption capacity (346.0 mg g −1 ). With the introduction of Hf or Ti, the chemical coordination environment changed, which resulted in defective structures of MOFs. Such defective structures increased the adsorption active sites, changed the surface charges and enlarged pores. Based on the characterization by FT-IR, XPS, and zeta potential, it was identified that the electrostatic attraction, π-π stacking, hydrogen bonding and metal complexation were the driving force for the high adsorption capacity of the bimetallic MOFs. The as-prepared MOFs displayed good stability and reusability. This work provides a great prospect for the design and application of bimetallic defective MOFs in cephalosporins removal in environmental water.
研究领域:
环境科学
·
材料科学
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF CHEMICAL THERMODYNAMICS
·
2022
·
IF 3.269
Di Fan,Zidan Cao,Yu Li,Tao Li,Baozeng Ren
The mole fraction solubility data of flavoxate hydrochloride in twelve experimentally selected solvents were measured at atmospheric pressure by the laser monitoring method. The experimental temperature range was 278.15 to 328.15 K. The solubility of flavoxate hydrochloride showed a nonlinear increase with temperature increase. At a fixed experimental temperature, the order of solubility is: ethylene glycol > methanol > 2-methoxyethanol ≈ dimethyl sulfoxide > N -Methyl-2-pyrrolidone > water > 2-propoxyethanol > 2-ethoxyethanol > ethanol > n -butanol > n -propanol > acetonitrile. Also, solubility data were correlated by two semi-empirical models and three activity coefficient models. From the average relative deviation and root mean square deviation data of the five models, it can be seen that the Modified Apelblat model has the best correlation. Furthermore, in this work, the effect of solvent on the solubility of flavoxate hydrochloride was analyzed using the KAT-LSER model. Furthermore, the thermodynamic parameters (Δ dis G 0 , Δ dis H 0 , Δ dis S 0 ) of the dissolution process of flavoxate hydrochloride were calculated by the Van’t Hoff model. The data indicate that the dissolution process of flavonoid hydrochloride in twelve experimentally selected solvents is endothermic and entropy-driven.
研究领域:
药物化学
·
物理化学
✓ 已验证
产品关联
DOI
高影响因子
CHEMOSPHERE
·
2023
·
IF 8.8
Yan Wang,Yueyong Jiang,Yong Zhang,Xiaolin Liu,Sen Sun,Shiyi Qin,Jiaqi Huang,Bowei Chen
A novel amidoxime-functionalized magnetic hydroxyapatite (AFNH) was successfuly fabricated to extract uranium from aqueous solution and seawater. The introduction of amidoxime group not only increased the number of active site of AFNH to speed up the adsorption rate and increase the extraction capacity, but also adjusted the optimal extraction pH from 4 to 8, which was beneficial for capturing uranium from seawater. The maximum adsorption capacity and adsorption efficiency at pH 8 were 945.2 mg g −1 and 99.2%, respectively. AFNH still had good removal efficiency (above 90%) after five cycles, indicating the good regeneration of AFNH. After uranium adsorption, AFNH could be easily recycled by magnetic separation due to its magnetism. In simulated seawater, AFNH also showed excellent uranium removal performance with high adsorption efficiency (84.9%) and adsorption capacity (1.70 mg g −1 ). Furthermore, the 14-day uranium extraction capacity of AFNH in natural seawater could reach 5.93 mg g −1 . The SEM, FTIR, XRD and XPS analyses showed that the enhanced uranium extraction performance of AFNH was mainly attributed to electrostatic interaction, complexation and co-precipitation. In conclusion, AFNH was expected to be a candidate as adsorbent with great potential in extracting uranium from seawater.
研究领域:
材料科学
·
环境科学
✓ 已验证
DOI
PubMed
高影响因子
危险品化学品经营许可证（带存储）