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Monoalkyl Esters of Isoalkylphosphonic Acid as Extractants in rare earth separation

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Journal of rare earths 1992年第2期10卷 142-147页

作者：陈德朴钟攸兰梁树权 Institute of Chemistry Academia SinicaBeijing 100080China

Four monoalkyl esters of isoalkylphosphonic acids have been studied for the chromatographic separation of rare earths (RE).The relationship between distribution ratios and acid concentration of the eluants for samarium and ytterbium has been *** characteristics of these extractants loaded onto macroreticular poly (methyl methacrylate) resin beads for the separation of lanthanum,cerium,praseodymium and neodymium have been *** the extractants studied,mono(1-methylheptyl) ester of isooctylphosphonic acid was found to be the best for RE *** acidity for separation is lower than any known P-containing extractants for the same *** instance,with 1.73 mol·L^(-1) nitric acid as eluent,thulium,ytterbium and lutetium can be separated *** extractant-loaded resins possess high column efficiency with good kinetic *** extraction mechanism was also explored.

关键词： rare earth separation Monoalkyl isoalkylphosphonates Extractant-loaded resins Extraction mechanism

Study of Transport and separation of rare earth Ions through the Emulsion Liquid Membrane of Bis(2,4,4-trimethylpentyl)phosphinic Acid-Span 80-Toluene

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Journal of rare earths 1993年第4期11卷 241-245页

作者：李克安邹长英姚晓华童沈阳 Department of Chemistry Peking UniversityBeijing 100871China Visiting scholar from Shanxi Worker Medical College

It is indicated from a study of transport of rare earth ions through the emulsion liquid mem- brane of bis(2,4,4-trimethylpentyl)phosphinic acid-Span 80-toluene that transporting rare earth ions com- pletely and rapidly was realized under the optimum experimental conditions:1.0×10^(-3)～3.0×10^(-3)mol/L bis(2,4,4-trimethylpentyl)phosphinic acid and 2%～4%(W/V)Span 80 in toluene solution as membrane phase,0.50～2.0 mol/L HCl as inner phase,rare earth ion solutions with pH 3.5～5.0 as outer ***- cording to the differences of transport behavior for rare earth ions,it is possible to separate rare earth ions from mixed solutions of rare earth ions by this liquid membrane system.

关键词： Emulsion liquid membrane Ionic transport rare earth separation Bis(2,4,4-trimethylpentyl)phosphinic acid(Cyanex 272)

Research and Application Progress in Countercurrent Solvent Extraction

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Journal of rare earths 2004年第5期22卷 576-581页

作者：贾江涛吴声廖春生严纯华 State Key Lab of rare earth Materials Chemistry and Applications Beijing Peking University 100871 (China ) Beijing Institute of Founder rare earth Sci & Tech. Co. Ltd. Beijing 100871 China Beijing Institute of Founder rare earth Sci & Tech. Co. Ltd. Beijing 100871 China

In this article, the recent progress made by Peking University is briefly introduced. Based on Theory of Countercurrent Extraction established by Prof. Guangxian Xu, the static equilibrium and dynamic process for two- and three-outlet countercurrent extractions, and designed the optimized parameters for the real cascades to separate different rare earth minerals, which can be scaled-up to the industrial process without any further experimental verification were systematically investigated. In order to stabilize the quality of products and improve the capability of automation for extraction process, we have also established an (()^(241)Am) stimulated X-ray fluorescent energy dispersive method to detect the elemental composition in both organic and aqueous phases, which can be used as an on-line analysis method in practice. Furthermore, the expert system and the control software with open- and close-loop models have been set up. Combined with the detected data from on-line analysis, the flow-rates of extracting, feeding, scrubbing and stripping solutions can be (controlled) in an optimum status for the industrial cascades. In addition, we have developed a new multi-input and multi-output countercurrent extraction process for separating multi-component rare earth mixture with lower chemical cost and pollution.

关键词： countercurrent extraction rare earth separation optimized process rare earths

Automation System in rare earths Countercurrent Extraction Processes

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Journal of rare earths 2001年第1期19卷 6-10页

作者：贾江涛严纯华廖春生吴声王明文李标国 Peking Univ Beijing Inst Founder Rare Earth Sci & Technol State Key Lab Rare Earth Mat Chem & Applicat Beijing 100871 Peoples R China

Based on the countercurrent extraction theory for optimized designing and simulating, the rare earth separation processes, the selection of the detecting points (stages) and on-line analysis for elements, the simulation of open loop response and its response speed, the diagnosis and the regulative prescription for running the solvent extraction cascades were studied.

关键词： rare earths automation rare earth separation open loop response feedback feedforward

separation of Neighboring REElementsfrom Sm_2O_3Eu_2O_3Gd_2O_3 System by a Stepwise ChlorinationChemical Vapor Transport Reaction

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Journal of rare earths 1999年第3期17卷 178-181页

作者：孙艳辉王之昌郭雷 NE Univ Technol Dept Chem Shenyang 110006 Peoples R China Chinese Acad Sci Inst Appl Ecol Shenyang 110015 Peoples R China

The mutual separation characteristics were investigated for the neighboring Sm, Eu and Gd from their ternary oxide mixture Sm 2O 3 Eu 2O 3 Gd 2O 3 by a stepwise chlorination chemical vapor transport reaction within 6 h using AlCl 3 as complex former. The rare earth chlorides were more readily transported and concentrated in the middle temperature range of 980～1100 K and the transport efficiency was in the order of Sm≈Gd>Eu. The separation factor, expressed as molar ratio for the resulting chlorides, was 1 70 for Eu∶Sm, 1 88 for Eu∶Gd, 1 24 for Sm∶Gd in the higher temperature region, and 2 76 for Sm∶Eu, 2 83 for Gd∶Eu and 1 12 for Gd∶Sm in the lower temperature region, respectively. All results are much higher than those of the conventional wet process.

关键词： rare earths Chemical vapor transport rare earth separation Sm 2O 3 Eu 2O 3 Gd 2O 3 system