Journal of the Taiwan Institute of Chemical Engineers
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2018
·
IF 3.849
Keyu Cui,Baihui Gao,Meng Tai,Bin Su
Rapid development of rare earth industry has led to an increasing demand for highly purified rare earth elements (REEs). The combination of ion-imprinted technique (IIT) and membrane separation technique (MST) is recently regarded as a promising strategy for selectively separating specific ions from multiple REEs. In this work, a facile bionic strategy for preparation of Gd (III)-imprinted membranes (GIMs) were developed via interlaced stacking of one-dimensional Gd (III)-imprinted carbon nanotubes (GICNTs) and two-dimensional polydopamine-modified graphene oxide (pDA@GO). Polydopamine was synthesized on graphene oxide to large enhance the interfacial adhesion, and ion-imprinting polymerization is implemented on carbon nanotubes (CNTs) by direct cross-link of linear polymers. The obtained materials are characterized in detail by FTIR, SEM, TEM and AFM to explorer the evolution of chemical composition and morphology. Selectivity towards Gd (III) is obtained by isothermal adsorption, kinetic adsorption and time-depended permeation. Isothermal and kinetic models are fitted with adsorption data to obtain the mechanism of selective separation on GIMs. The as-synthesized GIMs with high permeation selectivity (2.91 and 2.49) towards Gd (III) and stable permeation regeneration would potentially be applied to separation and purification of specific ions form multiple REEs.
研究领域:
材料科学
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化学工程
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环境科学
✓ 已验证
DOI
高影响因子
CHEMICAL ENGINEERING JOURNAL
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2018
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IF 6.735
Tingliang Xie,Minxuan Chen,Cong Xu,Jing Chen
Microextractors are known to provide high mass transfer rates for the extraction and separation of rare-earth elements (REEs). High-throughput microextractors are essential for industrial-scale production of REEs, but few practical studies have been conducted to date. In this work, a chaotic advection microextractor, i.e., a three-stage microextractor, was designed and demonstrated to extract Pr(III) and Ce(III) efficiently from nitric acid media at high throughputs by using 2-ethylhexyl phosphoric acid-2-ethylhexyl ester (P507) and sulfonated kerosene as an extraction agent and a diluent, respectively. Flow visualization experiments showed that the dispersed phase could be effectively broken into small droplets owing to vortex and recirculation flows. Microextraction experiments performed under optimal extraction conditions indicated that at low throughputs, the concentration ratio D , extraction efficiency E , and separation factor β decreased with an increase in the throughput, whereas at high throughputs, D , E , and β increased with an increase in the throughput. An extraction efficiency close to that of co-current balanced extraction was successfully achieved, even at a high total throughput of 100 mL/min and a rather short residence time of 0.029 s. Thus, the chaotic advection microextractor features a high throughput and high extraction efficiency, which are appropriate for the high-efficiency extraction and separation of REEs.
研究领域:
化学工程
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分离科学
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稀土冶金
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微流控技术
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过程强化
✓ 已验证
DOI
高影响因子
SEPARATION AND PURIFICATION TECHNOLOGY
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2019
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IF 5.107
Hongmin Cui,Xuejiao Feng,Jinsong Shi,Wengang Liu,Nanfu Yan,Guohua Rao,Wei Wang
Separation of rare earth elements (REEs) from dilute solutions using liquid-liquid extraction is often plagued by third phase formation and multiple sequential extraction steps. A new system based on the N, N-di(2-ethylhexyl)-diglycolamide (DEHDGA) grafted polymer resin, used for the efficient separation of RE(III) are proposed. Upon grafting of DEHDGA ligand, the resulting polymer resin was evaluated for its RE(III) adsorption performance. By using a combination of pH-dependent adsorption, kinetics and equilibrium adsorption isotherms experiments, the results suggest that adsorption behavior of the resin for RE(III) is mainly influenced by pH, and thus a competitive adsorption model is proposed to simultaneously describe the adsorption of RE(III) and protons. The proposed resin demonstrates enhanced selectivity towards RE(III) in the presence of Al(III) and Fe(III) compared to the DGA-normal resin at pH 3.0. These results establish that the polymer skeleton could provide a favorable geometry of DEHDGA ligand for complexing RE(III) through the carbonyl and ether groups, which is supported by the FT-IR and XPS analysis of prepared RE(III)-loaded resin. Furthermore, the polymer resin could be reused after four consecutive cycles without substantial loss of adsorption ability, offering a facile process for highly efficient REEs separation from a low concentration of leaching solution.
研究领域:
化学工程
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材料科学
✓ 已验证
产品关联
DOI
高影响因子
Separations
·
2025
·Vol. 12
·期 11
·303
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IF 2.7
Ruiyi Sun,Fan Li,Yu Xie,Na Sui,Yong Li,Junlian Wang
In this study, two γ-carbon-substituted dialkylphosphinic acids—symmetrical di-(3,5,5-trimethylhexyl)phosphinic acid (P355) and unsymmetrical (2-ethylhexyl)(3,5,5-trimethylhexyl)phosphinic acid (P227-355)—were synthesized via a precise free radical addition method. Their chemical structures were fully characterized using ESI-HRMS,1H NMR,31P NMR, and FT-IR. Their middle REE extraction/separation performance, anti-emulsification behavior, and underlying mechanisms were investigated. Key results showed that P355 had better Dy saturation capacity (357.51 mg/L) and good selectivity for middle REEs (their average value ofβN + 1/N= 3.18), while P227-355 showed higher back-extraction efficiency (≈90% Dy stripping at ≥0.02 mol/L H2SO4). Methyln-pentyl ketone (MNPK) eliminated emulsification and boosted saturation capacity (324.18 mg/L Sm and 357.51 mg/L Dy for P355). Mechanistically, the extraction followed cation exchange (Sm3++ 2(HL)2↔ Sm·L3·(HL) + 3H+); MNPK formed hydrogen-bonded associates (HL·MNPK) with free extractants, slightly reducing the effective concentration of (HL)2but not altering the core cation exchange mechanism.
研究领域:
湿法冶金
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稀土元素分离
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溶剂萃取
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无机合成
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配位化学
✓ 已验证
产品关联
DOI
高影响因子
SOLVENT EXTRACTION AND ION EXCHANGE
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2020
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IF 1.988
Sherif M. Ibrahim,Yan Zhang,Yun Xue,Suliang Yang,Fuqiu Ma,Guoxin Tian
The extraction of Nd(III), Gd(III), and Er(III), which represent light, middle, and heavy lanthanides, respectively, from chloride solutions has been carried out by using N,N-di(2-ethylhexyl)-diglycolamic acid (HDEHDGA, HA) diluted in kerosene as the organic phase. The results from the slope analysis method indicate that the extraction of Ln(III) with HDEHDGA is mainly governed by the cation-exchange reaction mechanisms in the low pH region (pH 1.2–2.7). The obtained data reveal that the extracted species in the organic phase might be LnA3∙HA(1~2), which consist of a core of 1:3 LnA3 complex and one additional neutral HA molecule for light Ln(III) or two for heavy Ln(III) associated with the core in the outer coordination sphere. The dependency on the temperatures indicates that the extraction of Ln(III) with HDEHDGA is exothermic and is mainly driven by the exothermic enthalpies crossing the whole Ln(III) series. The extraction of the whole Ln(III) series (except for Pm(III)) and Th(IV) has also been evaluated. HDEHDGA provides remarkable extraction capability with considerable separation factors (SF) for adjacent light Ln(III) pairs (SFCe/La = 6.8, SFPr/Ce = 3.3, SFNd/Pr = 2.5, and SFSm/Nd = 3.5), but relatively poor selectivity for the adjacent heavy Ln(III) pairs. It also presents very good selectivity/extractability for Th(IV) over the light Ln(III) ions (SFTh/La = 1362 and SFTh/Ce = 200). These properties make HDEHDGA a promising extractant for separating Th(IV) from light Ln(III) ions and for separating light Ln(III) ions from each other, which coexist significantly in some Rare Earth (RE) minerals, especially monazite and bastnaesite.
研究领域:
湿法冶金
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稀土元素分离
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溶剂萃取
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无机化学
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核化学
✓ 已验证
DOI
高影响因子
Inorganics
·
2025
·Vol. 13
·期 9
·296
·
IF 3
Ming Huang,Shunyan Ning,Juan Liu,Lifeng Chen,Mohammed F. Hamza,Yuezhou Wei
This work develops a novel phosphate-functionalized extraction resin (HEHEHP + Cyanex272)/SiO2-P via the vacuum impregnation method for efficient separation of light rare earth element impurities from lanthanum (La3+) in nitric medium through synergistic extraction. Batch experiments have demonstrated superior adsorption selectivity toward impurity ions over La3+in a pH 4 nitric acid solution. Column studies confirmed exceptional performance under ambient conditions, achieving a lanthanum treatment capacity of 120.6 mg/g and over 98% impurity removal, which surpasses most reported values. Notably, this purification process enables direct production of purified La3+solutions through a single-column system without desorption, significantly enhancing efficiency and reducing costs. Mechanistic insights revealed combined ion exchange and coordination interactions between metal ions and P-OH/P=O groups, corroborated by advanced characterization and density functional theory calculations. These findings indicate a higher binding affinity of light rare earth compared with La3+. This strategy provides a scalable approach for ultra-high-purity lanthanum compound production in advanced optical and electronic applications.
研究领域:
湿法冶金
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稀土元素分离
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材料科学
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分离技术
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环境化学
✓ 已验证
产品关联
DOI
高影响因子
SEPARATION AND PURIFICATION TECHNOLOGY
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2021
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IF 7.312
Kaibo Hu,Hongshuai Gao,Yi Nie,Haifeng Dong,Junjun Yan,Xiangping Zhang,Fujian Li
The efficient extraction separation of yttrium (Y) from holmium (Ho) and erbium (Er) is always difficult because of their similar physical and chemical properties. In this work, three pyridine carboxylic acid ionic liquids were synthesized and used to extraction of Y. The effects of aqueous phase acidity, extraction time, extractant concentration, temperature and alkyl chain length of ionic liquids on extraction of Y were investigated systematically. The extraction efficiency of [(CH 2 ) 7 COOHpyr][NTf 2 ] for Y increased with an increase in pH, and could reach 99.3% at a pH of 2.5. Meanwhile, the extraction process could achieve equilibrium completely within 5 min. In addition, both the separation coefficients of Ho/Y and Er/Y were greater than 2, which were higher than other ionic liquid extractants. At last, 98.5% of Y could be stripped from the loaded ionic liquid phase with a single step using 0.04 mol/L HCl, and the extraction efficiency of the [(CH 2 ) 7 COOHpyr][NTf 2 ] for Y still maintained about 98% after 8 cycles. A possible cation exchange extraction mechanism was proposed by slope analysis and FTIR spectroscopy.
研究领域:
湿法冶金
·
稀土元素分离
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离子液体
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溶剂萃取
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无机化学
✓ 已验证
DOI
高影响因子
SEPARATION AND PURIFICATION TECHNOLOGY
·
2023
·
IF 8.6
Ruihui Wu,Ronghao Liu,Xiaoxia Liu,Jianwei Zhang,Wenfeng Xue,Yanzhao Yang
The recovery of Nd(III) from NdFeB permanent magnets is gaining increasing attention. In the rare earth elements separation industry, wastewater produced through saponification has become a serious environmental problem. In this work, a novel non-saponification P350-N235 synergistic extraction system was established for the extraction of Nd(III) from nitric acid medium. Almost 100% of Nd(III) was extracted by using a P350-N235 system when the molar fraction (X) of P350 was 0.3. And the synergistic enhancement factor R max reached 60.03. Firstly, the effects of time, pH, volume ratio and other variables were investigated to determine the extraction behaviors. Response surface methodology (RSM) was used to optimize the extraction conditions. The mechanism of synergistic extraction was investigated by FT-IR, UV–vis, NMR methods and ESP maps, indicating that the composition of the extracted complex was Nd(NO 3 ) 3 ·(P350) 2.5 (N235) 2.5 . Then, the extraction thermodynamics and kinetics were also thoroughly investigated, the extraction process is demonstrated to be a spontaneously exothermic reaction. In the NdFeB leaching solution, the synergistic system showed excellent separation factor (β) for Nd/Sm (1.43), Nd/Gd (7.33), and Nd/Dy (9.81). Finally, after 5 cycles, the P350-N235 synergistic system maintained high extraction efficiency. In conclusion, this study overcame the saponification problem in traditional extraction techniques and proposed an environmentally friendly green extraction system.
研究领域:
环境科学
·
化学工程
·
材料科学
·
稀土元素分离
✓ 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）