MICROPOROUS AND MESOPOROUS MATERIALS
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2017
·
IF 3.615
Yu Liu,Zimo Lou,Yue Sun,Xiaoxin Zhou,Shams Ali Baig,Xinhua Xu
In this study, SiO 2 -EDTA was prepared by silanization reaction between N-(trimethoxysilylpropyl) ethylenediamine triacetic acid, trisodium salt (EDTA-silane) and hydroxyl groups for enhanced removal of Pb(II), Pb(II)-Cit (the clathrate generated by Pb(II) and trisodium citrate dehydrate(Cit)) and Pb(II)-EDTA(20%) from aqueous solutions. SiO 2 -EDTA composites were characterized using SEM, TEM, EDX-mapping, FTIR, XPS and TGA analyses. The influence of solution pH, initial concentration, contact time and co-existing interferents were also studied. Results demonstrated that the composite successfully adsorbed 147.52, 107.65 and 124.18 mg g −1 of Pb(II), Pb(II)-Cit, and Pb(II)-EDTA (20%), respectively with the initial Pb(II) concentration of 100 mg L −1 . Kinetics study revealed that the adsorption rate was significantly high at the beginning and then reached to equilibrium within 1.0 h. Moreover, Pb(II) adsorption capacities were found to considerably affected by co-existing cations and not inhibited by natural organic matter (NOM). Characterization analyses confirmed that EDTA was successfully assembled on SiO 2 which had been used as a supporting matrix due to its huge specific surface area. Findings from this study suggested that the present composite could be considered as a promising adsorbent for large scale treatment of wastewater containing elevated Pb(II) concentration.
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
ELECTROCHIMICA ACTA
·
2018
·
IF 5.116
Yue Song,Tianran Sun,Long Cang,Song Wu,Dongmei Zhou
Further research into more cost-effective methods to treat toxic metal-ethylenediaminetetraacetate (Me-EDTA) complexes is required due to their high bioavailability. In this study, we compared electrodialysis (ED) with different compartment designs (2-, 3- and 4-compartment designs) and electrochemical oxidation (EO, 1-compartment design) to treat a dilute Cu(II)-EDTA solution (1 mM). After a 48-h treatment with a constant current applied at 32 mA, the Cu removal efficiencies were achieved at 49%, 87%, 79% and 96% for 1-compartment EO and 2- to 4-compartment ED, respectively, and the total organic carbon concentrations decreased from 138 mg/L to 100, 64, 57 and 39 mg/L, respectively. The energy consumptions for 1-compartment EO and 2- to 4-compartment ED were 7.7, 8.4, 13.9 and 15.4 W h, respectively. Based on all above results, the most cost-effective design was determined to be the 2-compartment ED. Moreover, the 3- and 4-compartment ED treatments have faster contaminant removal kinetics than 1-compartment EO and 2-compartment ED. This study clarified the mechanisms of the migration and the transformation of Cu-EDTA during EO and ED with different membrane combinations, which is helpful for improved selection of compartment design for metal-chelate complex removal.
研究领域:
环境科学
·
化学工程
✓ 已验证
产品关联
DOI
高影响因子
TALANTA
·
2024
·
IF 5.6
Renjie Li,Haizhe Zhang,Weiqi Leng,Zhipeng Liu,Jiangtao Shi
At present, excessive Fe 3+ in daily water has become a threat to human health. Among the conventional detection methods for Fe 3+ , fluorescent probes have been applied on a large scale due to their simplicity and efficiency. However, the currently available fluorescent probes are difficult to synthesize, costly and environmentally unfriendly, limiting their applications. In this work, a fluorescent extract of Pterocarpus wood was successfully obtained, and the structure of some coumarin-based molecules in this extract was determined by 2D-NMR. Subsequently, the intensity of this fluorescence was optimized using response surface methodology (RSM), resulting in a high-intensity fluorescent probe. The probe was sensitive to the concentrations of Fe 3+ and MnO 4 − , and could efficiently detects Fe 3+ in the range of 2.7 μM–8.0 μM, with LOD and LOQ reaching 1.06 μM and 3.20 μM, respectively. Moreover, based on the strong complexation property of EDTA on Fe 3+ , this work designed the "switch-on" fluorescent probes . The experiment shows that both static and dynamic quenching exist in this system. The mechanism of complexation and oxidation of fluorescent molecules by the quencher is interpreted in the quenching reaction. In addition, the fluorescent probe has a high yield and low cost, it also performs well in actual water sample tests. This method is expected to be developed as a new way on Fe 3+ detection.
研究领域:
分析化学
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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 MOLECULAR STRUCTURE
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2019
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IF 2.12
Lijuan Huang,Xin Zhang,Zhuoyong Zhang
Terahertz time-domain spectroscopy (THz-TDS) provides a novel approach for the coordination compounds characterization. In this paper, the THz absorption spectra of iron complexes and M-EDTA (M = Cd 2+ , Cu 2+ , Ni 2+ , Co 2+ , Fe 2+ , Fe 3+ , Mn 2+ , Cr 3+ ) complexes were investigated. Comparing to the infrared (IR) spectra of those compounds, the THz spectra can provide unique chemical and intermolecular vibrational information. The M − O and M − N vibrational modes in the THz-TDS spectra of M-EDTA complexes reveal the vibrational information of intermolecular interactions . Characteristic absorption bands in the THz spectra of various complexes and ligands are observed. THz absorption spectra of iron complexes and different ligands exhibited characteristic absorption bands in 0–2.2 THz region. These characteristic bands can be used to characterize and identify different complexes and ligands. The molecular vibrational information in the THz spectral band provides the unique fingerprint for further study of coordination compounds identification and structure characterization.
研究领域:
化学
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材料科学
·
光谱学
✓ 已验证
产品关联
DOI
高影响因子
RSC Advances
·
2016
·Vol. 6
·期 103
·101725-101730
·
IF 3.289
Yanan Zhang,Xuedong Gao,Yun Yan,Jide Wang,Jianbin Huang
Removal of chelated metal ions from water remains a challenge in the treatment of industrial waste water since the chelating complexes are extremely stable, which means that precipitation is difficult. We report the elegant cooperativity of electrostatic interaction, coordinating interaction, and hydrophobic effects, which allows facile flocculation of Cu–EDTA through the stepwise addition of polyethyleneimine (PEI) and sodium dodecyl sulphate (SDS). The electrostatic interactions are important in ‘initiating’ the coordination between PEI and Cu–EDTA, and the hydrophobic interaction between SDS and PEI allows cross-linking of the PEI/Cu–EDTA complex to generate a precipitate. With this facile protocol, 97% of the Cu–EDTA complex in the waste water can be removed, and the residual level of Cu–EDTA can be lowered to below 2 mg L−1. Such cooperativity of noncovalent interactions is of great potential interest in the removal of chelated metal complexes from industrial water.
研究领域:
环境科学
·
化学工程
✓ 已验证
产品关联
DOI
高影响因子
CHEMOSPHERE
·
2019
·
IF 5.108
Wuming Xie,Fengping Zhou,Xiaolin Bi,Dongdong Chen,Zijun Huang,Yuhui Li,Shuiyu Sun,Jingyong Liu
Nickel (Ⅱ)−ethylenediaminetetraacetic acid (Ni−EDTA) complexes are widely present in electroplating effluents. Owing to its chemical stability, Ni−EDTA is hardly removed in traditional Fenton/Fenton-like processes with conventional iron (Fe)−based catalyst. In this study, oxygen vacancies were introduced into our highly efficient and novel Fe 3 O 4 @γ−Al 2 O 3 catalysts using Cu doping for Ni−EDTA decomposition in Fenton−like system. Without noble−metal cocatalyst, the introduction of oxygen vacancies in Cu−doped Fe 3 O 4 @γ−Al 2 O 3 catalysts exhibit excellent Fenton−like activity even in neutral or alkaline conditions. Experimental results revealed that, without the aid of extra energy, Ni−EDTA complexes could be effectively decomposed over oxygen vacancies−based catalyst. Electron paramagnetic resonance (EPR), X−ray photoelectron spectroscopy (XPS), oxygen temperature−programmed desorption (O 2 −TPD), and hydrogen temperature−programmed reduction (H 2 −TPR) were used to get a deep insight into the decomposition mechanism. Additionally, by employing the Al−containing support, stable layered double−hydroxide phases of Ni Al could be formed, indicating that a synergy of oxidation and adsorption could simultaneously take place, which led to the recovery of released Ni 2+ ions and also reduction in secondary pollution. To investigate the decomposition process of Ni−EDTA over oxygen vacancies−based catalyst, liquid chromatography−quadrupole/electrostatic field orbitrap high resolution mass spectrometry (LC−MS/MS) was employed to identify the generated intermediates, and thus, a plausible decomposition pathway was successfully conceived.
研究领域:
环境科学
·
催化化学
✓ 已验证
DOI
PubMed
高影响因子
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