HYDROMETALLURGY
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2022
·
IF 4.217
Xiayu Liang,Qingle Zeng
Samarium (Sm), as one of the lanthanide elements, has a broad application prospect in the synthesis of samarium cobalt permanent magnet materials with high temperature stability, corrosion resistance and oxidation resistance . Due to the unlimited demand of Sm(III), recycling of Sm(III) waste is an effective method to balance economy and supply. In this paper, three novel morpholine carboxylic acid ionic liquids (ILs) were rationally designed and successfully synthesized for the extraction of Sm(III). The effects of alkyl chain length of the ionic liquids, solution acidity, contact time, extractant concentration and temperature were tested in terms of the extraction performances. The results revealed that [(CH 2 ) 7 COOHmor][NTf 2 ] had the optimal extraction capacity, as well as the extraction efficiency of Sm increased with the increase of pH, reaching >99.9% when the pH was 1.8. In addition, the extraction equilibrium could be achieved within 1 min. Moreover, the slope analysis and FTIR spectral studies proposed a cation exchange extraction mechanism for Sm(III) by [(CH 2 ) 7 COOHmor][NTf 2 ]. The loaded Sm(III) in organic phase was easy to strip with 0.05 mol/L of HNO 3 , and the [(CH 2 ) 7 COOHmor][NTf 2 ] remained stable after 5 cycles. The research of transition metal extraction revealed that Sm(III) could be selectively separated from Ni(II) and Co(II) by adjusting the pH value of the solution. Finally, under the optimized extraction conditions, Sm 2 O 3 with 83.9% yield was obtained by the extraction-stripping-precipitation-calcination process, through the large-scale recovery applications of the simulated waste liquid .
研究领域:
化学工程
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材料科学
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DOI
高影响因子
JOURNAL OF RADIOANALYTICAL AND NUCLEAR CHEMISTRY
·
2018
·Vol. 315
·期 3
·581-593
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IF 1.181
Jie Fengping,Bai Zhishan,Yang Xiaoyong
A microemulsion consisting of sodium laurate, n -pentanol, n -heptane and NaCl solution was investigated for Co(II) extraction. The dilution method and conductivity method were used for the determination of structural parameters of sodium laurate/pentan-1-ol/heptane/NaCl microemulsion system. Co(II) was found to be extracted into the microemulsion phase due to the compound formation of [CoCl] + [R 11 COO] − , which was confirmed by the continuous variation of R 11 COONa concentration. Moreover, the effects of cosurfactant, the contact time, the phase ratios, PH and the NaCl concentration in feed solutions on the cobalt extraction yield were investigated. Under the optimum conditions, the extraction percentage of Co(II) could reach 98.9%.
研究领域:
化学
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环境科学
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DOI
高影响因子
SEPARATION AND PURIFICATION TECHNOLOGY
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2023
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IF 8.6
Hui Cao,Yinhao Dai,Leliang Wu,Chengdu Qi,Linlin Hou,Dequan Zhang,Yao Li,Chenmin Xu,Huan He,Shaogui Yang
Advanced oxidation processes based on peracetic acid (PAA) activation have received more attention in water treatment recently. In this study, the degradation of iohexol (IOH, a classical iodinated X-ray contrast media) in the Co(II)/PAA system under neutral conditions, which mainly produced carbon-centric radicals, was investigated. Results showed that IOH decomposition follows the pseudo-first-order kinetic with a rate constant of 0.283 min −1 . Appropriately increasing concentrations of PAA or Co(II) could promote the removal of IOH, while elevating the dosage of H 2 O 2 inhibits the elimination of IOH in the Co(II)/PAA system. The IOH elimination was affected by pH, with the best response in pH between 5 and 7 in the Co(II)/PAA system. Additionally, low Cl − doses have negligible effects whereas high Cl − impeded the breakdown of IOH. Br − , I − , HCO 3 − , H 2 PO 4 − and humic acid suppressed the degradation of IOH. Removal of IOH was significantly inhibited in three selected real water samples. Furthermore, six IOH degradation pathways, including H-abstraction, amide hydrolysis, amino oxidation, deiodination reaction, hydroxylate and elimination reaction, were proposed on the basis of the liquid chromatography-tandem mass spectrometry , ion chromatography and DFT theoretical calculations (Frontier electron densities and fukui functions) results. Finally, the ECOSAR assessment showed that some degradation byproducts were much more toxic than IOH parent, but were much more biodegradable. Overall, this study indicates a potential risk when applying the carbon-centric radicals involved in PAA-based AOPs to remediate halogenated organic pollutants in water.
研究领域:
环境科学
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化学
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DOI
高影响因子
Chemical Engineering Journal Advances
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2022
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IF 0
Na Yuan,Hongchao Li,Jieshu Qian
Determination of the concentration of peracetic acid (PAA) in the presence of H 2 O 2 is a great challenging problem due to the similar chemical behaviors of the two species. In this study, we developed a new method for simultaneous measurement of PAA (0.5 – 10.0 μM) and total peroxides (i.e., PAA and H 2 O 2 with a molar ratio of 10:6.5), based on the catalytic oxidation of ABTS by separately using Co(II) and peroxidase (POD) as the catalysts. Owing to the unique catalytic activity of Co(II) towards PAA, the coexistent H 2 O 2 exhibits negligible effect on the determination of PAA. The value of absorbance at 415 nm increases linearly with increasing the concentration of PAA or total peroxides, and the sensitivities for PAA and total peroxides are as high as 5.31 × 10 4 and 9.07 × 10 4 M −1 cm −1 , respectively. In addition, the proposed ABTS method shows excellent feasibility and applicability, which make it suitable to be employed for detection in complicated water matrices.
研究领域:
分析化学
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环境科学
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DOI
NUCLEAR TECHNOLOGY
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2022
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IF 1.667
Yanhui Wang,Qiao Jiang,Yexin Yang,Jianfeng Cheng,Chenyang Bao,Yuelong Pan,Yu Liu,Gang Yang,Yangchun Leng,Xianguo Tuo
The alteration of the morphology of bentonite, a key barrier to isolating high-level radioactive waste in deep geological repositories under long-term interaction with groundwater, was studied. Bentonite colloids were prepared from Gaomiaozi bentonite, and its various properties were analyzed by various characterization methods. The effects of various factors on the adsorption of Cs(I) and Co(II) on bentonite colloids were investigated by batch static adsorption experiments. The results showed that the colloids were mainly composed of montmorillonite and were lamellar in shape, with a zeta potential of −enton mV and an average size of approximately 209.10 nm. The adsorption of Cs(I) and Co(II) by the colloids was a rapid process, and 31.78 and 88.24 mg/g, respectively, were adsorbed at equilibrium. Pseudo-second-order kinetic fitting showed that chemisorption plays a dominant role and acid-base interactions affect adsorption by influencing the stability of colloids and the chemical form of simulated nuclides. This work can be helpful for evaluating the safety of waste repositories.
研究领域:
环境科学
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放射性废物管理
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DOI
高影响因子
Polymers
·
2016
·Vol. 8
·期 11
·389
·
IF 2.944
Lihua Guo,Xinyu Jing,Shuoyan Xiong,Wenjing Liu,Yanlan Liu,Zhe Liu,Changle Chen
A series of alkyl- and aryl-substituted iminopyridine Fe(II) complexes1a–7aand Co(II) complexes2b,3b,5b, and6bwere synthesized. The activator effect, influence of temperature, and, particularly, the alkyl and aryl substituents’ effect on catalytic activity, polymer molecular weight, and regio-/stereoselectivity were investigated when these complexes were applied in isoprene polymerization. All of the Fe(II) complexes afforded polyisoprene with high molecular weight and moderatecis-1,4 selectivity. In contrast, the Co(II) complexes produced polymers with low molecular weight and relatively highcis-1,4 selectivity. In the iminopyridine Fe(II) system, the alkyl and aryl substituents’ effect exhibits significant variation on the isoprene polymerization. In the iminopyridine Co(II) system, there is little influence observed on isoprene polymerization by alkyl and aryl substituents.Keywords:iminopyridine;Iron(II);Cobalt(II);isoprene polymerization;selectivity
研究领域:
化学
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高分子科学
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DOI
PubMed
高影响因子
Journal of Energy Storage
·
2024
·
IF 8.9
Huanzhong Zeng,Qianghong Wu,Rui Liu,Yuanyou Peng,Fuliang Zhu,Fen Ran
Cobalt is a common contaminated metal exists in industrial wastewater and is also widely used in the field of energy storage as electrode materials. Cobalt(II) is the most familiar water-soluble form of cobalt element and its emission to environment causes serious problems. Traditional physical and chemical methods are unable to fully eradicate cobalt(II) in wastewater, especially at low concentrations. Therefore, phytoremediation is proposed and myriophyllum spicatum is chosen as the subject for absorbing cobalt(II) presented in the simulated wastewater. The results show that the myriophyllum spicatum can prominently but finitely absorb cobalt(II) from simulant wastewater; in order to reuse recycled cobalt(II), the composite material is obtained after carbonization and is applied to supercapacitors as electrode material. Under the condition of a current density of 0.5 A/g in 6 M KOH, the specific capacitance is 275 F/g, where good charge storage capacity and rate performance are obvious compared with other non-activated biomass-derived carbon materials.
研究领域:
环境科学
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能源材料科学
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DOI
高影响因子
Journal of Materials Chemistry A
·
2015
·Vol. 4
·期 3
·1096-1104
·
IF 7.443
Hao Wu,Zhimin Chen,Jialin Zhang,Feng Wu,Chunying He,Bin Wang,Yiqun Wu,Zhiyu Ren
Cost-efficient, highly sensitive and stable sensing materials play a key role in developing H2S sensors. Herein, tetra-β-carboxyphenyloxyphthalocyanine cobalt(II) (cPcCo) has been successfully bonded on the surface of acidified multiwalled carbon nanotubes (aCNTs) by a facile two-step condensation reaction in the presence of N,N′-dicyclohexylcarbodiimide (DCC), using hydroquinone (HQ), p-aminophenol (PAP), and p-phenylenediamine (PPD) as linking molecules, respectively. The obtained cPcCo–B–aCNT (B= HQ, PAP, and PPD) hybrids display good dispersibility in ethanol, which is beneficial to construct uniform sensing devices. The cPcCo–B–aCNT sensors, with a loose network-like structure, present abundant exposed sensing sites, oriented transmission of charges, and unimpeded pathways for H2S diffusion, which endow the cPcCo–B–aCNT hybrids with excellent sensing performance, in terms of sensitivity, reliability, reproducibility, and detection limit. The detection limit of the sensors composed of cPcCo–B–aCNT hybrids towards H2S reaches the ppb-level at room temperature, which is about the same as the odor threshold level for humans. For the cPcCo–HQ–aCNT sensor, the response to H2S varies linearly with respect to its concentration from 20 to 160 ppb and from 320 to 2560 ppb, with the highest gas response of 2.5% to 80 ppb H2S and a low detection limit of 5 ppb. Furthermore, the linking molecules play a critical role in the sensitivity of H2S, as evidenced from the current–voltage characteristics. The systematic study developed here provides a valid way to fabricate other high-efficient H2S sensors.
研究领域:
材料科学
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化学传感器
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DOI
高影响因子
SCIENCE OF THE TOTAL ENVIRONMENT
·
2019
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IF 5.589
Zhangxiang Lin,Pei Yuan,Yuanyuan Yue,Zhengshuai Bai,Haibo Zhu,Tinghai Wang,Xiaojun Bao
Selective separation and recovery of Co(II)/Mn(II) from purified terephthalic acid (PTA) production wastewater is very important to reduce the Co(II)/Mn(II) catalysts consumption and control the pollutant discharge. This work employed zeolites NaA, NaX, and HZSM-5 with different pore sizes and Na(I) contents to selectively separate and recover Co(II)/Mn(II) from PTA wastewater and to understand the adsorption mechanism. It is found that only NaA can exclusively adsorb Co(II)/Mn(II) through ion-exchange without adsorbing any aromatic organic compound (AOC); oppositely, HZSM-5 shows the highest adsorption capacity for AOCs but almost no adsorption for Co(II)/Mn(II); and NaX exhibits moderate adsorption capacities for both Co(II)/Mn(II) and AOCs. Moreover, pH can significantly impact the adsorption of both Co(II)/Mn(II) and AOCs due to the competitive adsorption between H(I) and Co(II)/Mn(II) and the electrostatic repulsion between AOCs and zeolites. The adsorption kinetics, isotherms, and thermodynamics were also investigated to lay a good basis for process development. Importantly, bench-scale experiments for simulating the industrial operation were carried out, and the results show that the adsorption capacity of the NaA particles for Co(II)/Mn(II) from the industrial PTA wastewater is 9.1/8.6 mg/g, respectively, without adsorbing any AOC. Therefore, an efficient strategy to selectively separate and recover Co(II)/Mn(II) from PTA wastewater was successfully developed.
研究领域:
环境科学
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化学工程
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产品关联
DOI
PubMed
高影响因子
ACS ES&T Engineering
·
2021
·
IF 0
Zihao Zhao,Xinhong Li,Hongchao Li,Jieshu Qian,Bingcai Pan
The combination of Co(II) and peracetic acid (PAA) is an important alternative advanced oxidation process (AOPs), in which R-O• radicals including acetyloxyl radicals (CH3C(O)O•) and acetylperoxyl radicals (CH3C(O)OO•) have been considered to be the primary reactive species for the oxidative degradation of contaminants. However, it is still unclear how the active Co species participates in this process. In this study, we conduct a series of experiments including chemical probing, radical quenching, electron paramagnetic resonance (EPR), and Co(III) oxidation to investigate the degradation mechanism of contaminants in the Co(II)/PAA process, using bisphenol A (BPA) as target pollutant. On the basis of these results, we propose a Co(II)-PAA complex (Co(II)-OO(O)CCH3) to be the primary reactive species, while R-O• radicals and Co(III) (available as dimeric Co-peroxide species) derived from the decomposition of Co(II)-PAA complex are the minor contributors for the oxidation of BPA. Factors, including PAA concentration, Co(II) concentration, solution pH, inorganic anions, and natural organic matters (NOM), that might affect the oxidation performance of the Co(II)/PAA process were also investigated systematically. This study sheds new light on the mechanistic understanding of the Co(II)/PAA process for the oxidation of contaminants in water.
研究领域:
环境科学
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化学
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DOI
Chemosensors
·
2023
·Vol. 11
·期 3
·192
·
IF 4.2
Zhanpeng Ren,Jianying Wang,Chenglong Xue,Minghua Deng,Ziqin Li,Huibin Zhang,Chen Cai,Bing Xu,Xianbao Wang,Jinhua Li
A carbon dot-functionalized solution-gated graphene transistor (CD-SGGT) was designed and prepared via the modification of CDs on the gate of SGGT. The above CDs were hydrothermally synthesized using DL-thioctic acid and triethylenetramine as C, N and S sources. The average size of CDs was ~6.2 nm, and there were many amino and carboxyl groups on the CDs’ surfaces. The CDs was then used as a probe for preparation of CD-SGGT sensor for the cobalt(II) (Co2+) ions detection. The CD-SGGT sensor showed excellent sensitivity and high selectivity. Remarkably, the limit of detection (LOD) reached 10−19M. The linear detection range was obtained from 10−19to 10−15M. Additionally, the CD-SGGT also showed fast response and good stability.Keywords:carbon dots;graphene;transistor;cobalt(II) ions;high selectivity;high sensitivity
研究领域:
材料科学
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分析化学
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产品关联
DOI
高影响因子
DIAMOND AND RELATED MATERIALS
·
2024
·
IF 4.3
Junmei Liu,Yu Zhang,Xirui Miao,Haichao Li,Chunying Tao,Jin Liu,Xudong Yang
Novel nitrogen-doped carbon dots (N-CDs) were prepared by microwave method using o -phenylenediamine and formamide as raw materials, and the N-CDs were used successfully for sensing Co(II) on the basis of photoluminescence quenching. The structural characterization of the obtained N-CDs was thoroughly performed by transmission electron microscopy (TEM), Fourier transform infrared (FT-IR) and X-ray diffraction (XRD) spectroscopy. The optical properties were also determined by absorption and fluorescence spectra. N-CDs have bright yellow fluorescence emission and high quantum yield (29 %), with a detection limit as low as 0.38 μM. In order to detect Co(II) more conveniently and quickly, N-CDs/PVA fluorescence composite film was prepared by compounding N-CDs with polyvinyl alcohol. The fluorescence composite film combines the fluorescence characteristics of N-CDs and the stability of polyvinyl alcohol. The application range of Co(II) visual detector in the water environment is expanded.
研究领域:
材料科学
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环境科学
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分析化学
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产品关联
DOI
高影响因子
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