JOURNAL OF MOLECULAR LIQUIDS
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2022
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IF 6.633
Yangyang Wang,Xiaoxia Liu,Annie Yang,Ping Lv,Lixin Zhang,Yongnian Li,Yanzhao Yang
Selective recovery of gold and platinum from secondary resources is of great significance under the crisis of resource shortage. Hence, the optimal extractant 1-(2-(dimethylamino) ethyl)-4-methyl-piperazin bis(trifluoromethylsulfonyl)imide ([C 6 -Et-TMEDA-PIP][Tf 2 N] 2 ) was synthesized and screened out from five piperazine-based ionic liquids (ILs) to construct an IL-water system for Au(III) and Pt(IV) extraction. ILs have high hydrophobicity and low viscosity at room temperature, which can be used as both extractant and hydrophobic phase. The effects of IL dosage, metal concentration and acidity on the extraction efficiency were investigated. Under the optimal conditions, the extraction efficiency of 98.5% (Au(III)) and 97.5% (Pt(IV)) can be achieved. The anion exchange mechanism was verified through the combination of Ultraviolet visible spectroscopy (UV–vis), Nuclear magnetic spectra (NMR) and quantum chemical calculations. Besides that, the two-factor optimization of the extractant dosage and HCl concentration was carried out by Response surface methodology (RSM), and the effective separation of Au(III) and Pt(IV) was successfully achieved. Au(III)/ Pt(IV) was extracted into the IL phase as [Et-TMEDA-PIP + ][AuCl 4 - ] and can easily be stripped by reduction to Au(0)/Pt(Ⅱ) with H 2 C 2 O 4 /CS(NH 2 ) 2 -HCl, and each extraction ability maintained after 5 turns of extraction cycle experiments. Since the excellent behaviors showed in the multi-metal selective extraction and cycle experiments, the [C 6 -Et-TMEDA-PIP][Tf 2 N] 2 was regarded as the most potential system for Au(III) and Pt(IV) recovery from HCI medium.
研究领域:
化学
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材料科学
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环境科学
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分析化学
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF MEMBRANE SCIENCE
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2018
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IF 6.578
Yujian Yao,Meng Li,Xingzhong Cao,Peng Zhang,Wen Zhang,Junfeng Zheng,Xuan Zhang,Lianjun Wang
A new sulfonated diamine monomer , 4,4′-((1,4-phenylenebis(methylene))bis(azanediyl))dibenzenesulfonic acid (PMABSA) was synthesized and used as the sole aqueous reactant to fabricate a novel reverse osmosis (RO) membrane with trimesoyl chloride (TMC), in place of conventional m -phenylene diamine (MPD). The separation performance of the PMABSA/TMC membrane was optimized by the response surface method (RSM) by means of evaluating the pure water permeability (PWP) and salt rejection (R) to NaCl, and optimal results of PWP of 1.18 ± 0.03 L m −2 h −1 bar −1 , and R of 98.2 ± 0.4%, respectively, were achieved at 1.55 MPa. Owing to the rigid benzene ring in the center of the molecule, which may have a blocking effect during the interfacial polymerization (IP) process, the resulting barrier layer was less compact and had low thickness. Both molecular dynamics (MD) simulation and positron annihilation spectroscopy (PAS) revealed the creation of sufficient free volumes in the sulfonated polyamide matrix. Regardless of the slightly lower water permeation, the PMABSA/TMC membrane exhibited a superior rejection ability to all the ions compared to that of commercial SW30HR (Dow Chemical) in a model seawater separating test. Overall, all the results indicated the great potential of the novel membrane as a new choice of non-MPD RO membrane for seawater desalination.
研究领域:
材料科学
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化学工程
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环境科学
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水处理
✓ 已验证
DOI
高影响因子
Materials Today Nano
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2022
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IF 13.364
J. Wu,P. Wu,X. Weng,J. Lin,G. Owens,Z. Chen
Recently, the green synthesis of iron nanoparticles and associated hybrids using plant extracts has attracted much attention due to its low cost, simplicity and environmental friendliness . However, the exact formation mechanism is still unclear. In this study, the one step green synthesis of hybrid rGO/Fe NPs by a tea extract was examined using a response surface methodology (RSM) to obtain a high activity of rGO/Fe NPs. The results showed that the best conditions for synthesis were an extract concentration = 35 g/L, pH = 7, and temperature = 30 °C. The optimized hybrid produced could remove 99.9% of mitoxantrone (MTX) compared to only 78.9% when unoptimized. To better understand the formation process, characterizations by SEM , TEM, AFM , FTIR, XRD , Raman, and XPS were performed. Theses characterizations showed that the Fe NPs produced had a particle size of 25 nm which were deposited randomly across the rGO nanosheet with a thickness of approximately 1.5 nm, indicating that stable hybrid rGO/Fe NPs were successfully synthesized, where the green tea extract exhibited both reducing and capping/stabilizing behavior. Furthermore, the specific biomolecules in the green tea extract responsible for bio-reduction and stabilization were identified by GC-MS and LC-MS, which showed that catechins were the main reducing agents, while alkaloids, amino acids and phenolic acids were the main capping/stabilizing agents. Finally, a mechanism for synthesizing rGO/Fe NPs was proposed, where the polyphenols successfully reduced GO and complexed with iron ions to form amorphous ferric (and ferrous) polyphenol complex nanoparticles.
研究领域:
材料科学
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纳米技术
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环境科学
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分析化学
✓ 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）