Minerals
·
2021
·Vol. 11
·期 1
·61
·
IF 2.644
Wenjie Zhang,Xian Xie,Xiong Tong,Yunpeng Du,Qiang Song,Dongxia Feng
Solvent extraction is the most widely used method for separation and purification of rare earth elements, and organic extractants such as di(2-ethylhexyl) phosphoric acid (P204) and di(1-methyl-heptyl) methyl phosphonate (P350) are most commonly used for industrial applications. However, the presence of impurity ions in the feed liquid during extraction can easily emulsify the extractant and affect the quality of rare earth products. Aluminum ion is the most common impurity ion in the feed liquid, and it is an important cause of emulsification of the extractant. In this study, the influence of aluminum ion was investigated on the extraction of light rare earth elements by the P204-P350 system in hydrochloric acid medium. The results show that Al3+competes with light rare earths in the extraction process, reducing the overall extraction rate. In addition, the Al3+stripping rate is low and there is continuous accumulation of Al3+in the organic phase during the stripping process, affecting the extraction efficiency and even causing emulsification. The slope method and infrared detection were utilized to explore the formation of an extraction compound of Al3+and the extractant P204-P350 that entered the organic phase as AlCl[(HA)2]2P350(o).Keywords:Al3+;light rare earths;P204;P350;impurity
研究领域:
化学工程
·
材料科学
✓ 已验证
DOI
高影响因子
JOURNAL OF RARE EARTHS
·
2021
·
IF 3.712
Wenjie Zhang,Dongxia Feng,Xian Xie,Xiong Tong,Yunpeng Du,Yang Cao
Solvent extraction is the most important method for rare earth extraction and separation. Currently, di(2-ethylhexyl) phosphoric acid (HDEHP) and 2-ethylhexyl phosphonic acid mono-2-ethylhexyl ester (HEH/EHP) are widely used in industrial production, but there are still obvious deficiencies that require further research to resolve. In this paper, the unsaponification extraction of light rare earth ions in a hydrochloric acid medium by di(2-ethylhexyl) phosphoric acid-di(1-methyl-heptyl) methyl phosphonate (HDEHP-P350) system was studied. The results show that the addition of P350 reduces the extraction capacity of HDEHP, and also greatly reduces the concentration of acidity required for the back-extraction. It still has a good separation factor for light rare earths without saponification , and the extractant is not easy to emulsify. With an aqueous phase of pH = 2.85, and HDEHP mole fraction X HDEHP = 0.9 (compared with O/A = 2), the separation effect of light rare earth is the best, resulting in the separation coefficient β Ce/La = 3.39, β Pr/Ce = 1.67 and β Nd/Pr = 1.45, respectively. The loaded light rare earth ions extracted by HDEHP-P350 can be easily stripped when 2 mol/L HCl is used as the stripping agent. Finally, the extraction mechanism is discussed using a slope method, and the final structure of the extracted complex is determined to be RECl[(DEHP) 2 ] 2 P350 (o) , based on a combination of infrared spectra and 1 H NMR and 31 P NMR analyses.
研究领域:
化学工程
·
材料科学
✓ 已验证
DOI
高影响因子
JOURNAL OF INDUSTRIAL AND ENGINEERING CHEMISTRY
·
2023
·
IF 6.1
Yanli Zhang,Meixue Zhao,Xu Li,Qingping Xin,Xiaoli Ding,Lizhi Zhao,Hui Ye,Ligang Lin,Hong Li,Yuzhong Zhang
The incorporation of porous nano-fillers into mixed matrix membranes (MMMs) has a great impact on CO 2 separation. In this study, a series of F-Ln (Ln is the Light Lanthanide, Ln = La, Ce, Pr, Nd) nanosheets with mesoporous structure was fabricated as a filler in Pebax®1657 matrix to improve the performance of CO 2 separation. F-Ln nanosheets are uniformly distributed in the membrane and the mesoporous structure can construct multiple channels for CO 2 fast transport in Pebax/F-Ln MMMs. The pore diameter of nanosheet is in order: F-La > F-Ce > F-Pr > F-Nd, and the smaller pore diameter of nanosheets is beneficial to improve the CO 2 separation performance. In humidified conditions, Pebax/F-Nd-6 MMMs show optimum separation performance among MMMs, and the CO 2 permeability is up to 1265 Barrer and CO 2 /CH 4 selectivity is 36.7, which are 2.3 times and 1.9 times higher than pure Pebax and approaches 2019 upper bound. Meanwhile, to demonstrate the potential universal applicability of F-Ln nanosheets in CO 2 separation, XLPEO/F-Ce MMMs were fabricated to separate CO 2 /N 2 and the performance exceeds the 2019 upper bound. The efficient CO 2 separation performance of 2D F-Ln nanosheets with mesoporous structure in membranes reveals the potential application of these nanosheets in industrial CO 2 separation.
研究领域:
材料科学
·
环境工程
✓ 已验证
产品关联
DOI
高影响因子
ACS Omega
·
2019
·
IF 2.584
Sherif M. Ibrahim,Yan Zhang,Yun Xue,Suliang Yang,Fuqiu Ma,Yang Gao,Yu Zhou,Guoxin Tian
The complexation and selectivity of N,N-di(2-ethylhexyl)-diglycolamic acid (HDEHDGA/kerosene, HA) toward the light lanthanides, La(III), Ce(III), Pr(III), and Nd(III), are presented for the extraction from chloride media. In the low pH region (pH 1.8–2.8), the obtained data reveal that the extraction of Ln(III) is governed by cation-exchange mechanism and is driven by the negative change in enthalpy. The results from the slope analysis method suggest the formation of LnA3·(HA)1or2 in the extraction process. As major extracted species with a core of LnA3 in the first coordination sphere, LnA3 might connect with one or two additional HA molecules in the second coordination sphere by hydrogen bonding. The LnA3 core might share similar coordination geometry to those of 1:3 Ln(III) complexes (LnA′3) with water-soluble N,N-dimethyl-diglycolamic acid (HDMDGA, HA′) formed in aqueous solutions or in solid-state compounds. The correlation between the extraction with HDEHDGA (HA) as an extractant and the complexation with HDMDGA (HA′) as a chelator has been explored by interpreting the separation factors for HA with the difference in the stability constants for HA′. Consequently, the ratios of the stability constants of the corresponding 1:3 complexes (LnA′3) with HDMDGA could be reasonably translated to the separation factors (SFs) with HDEHDGA, providing a valuable approach for understanding the origin of the extraction/separation mechanism. By comparing the extraction selectivity of HDEHDGA with that of the currently deployed extractants in the industry such as P204, P507, and Cyanex 272, HDEHDGA offers outstanding selectivity with considerable SFs (SFCe/La = 6.68, SFPr/Ce = 2.79, and SFNd/Pr = 2.65) for light Ln(III) pairs under conditions of low acid concentrations.
研究领域:
化学
·
材料科学
·
环境科学
✓ 已验证
DOI
PubMed
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
·
稀土元素分离
·
材料科学
·
分离技术
·
环境化学
✓ 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）