Synergistic extraction of rare earth by mixtures of 2-ethylhexyl phosphoric acid mono-2-ethylhexyl ester and di-(2-ethylhexyl) phosphoric acid from sulfuric acid medium  

作　　者：黄小卫 李建宁 龙志奇 张永奇 薛向欣 朱兆武 

机构地区：[1]Institute of Metallurgical Resources & Environmental Engineering, Northeastern University [2]National Engineering Research Center for Rare Earth Materials,General Research Institute for Nonferrous Metals, and GRIREM Advanced Material Co. Ltd.

出　　处：《Journal of Rare Earths》2008年第3期410-413,共4页稀土学报（英文版）

基　　金：the National Natural Science Foundation of China (50674016);the National High Technology Research and Develop-ment Program of China (863 Program) ( 2006AA06Z123)

摘　　要：The extraction of Nd^3＋ and Sm^3＋, including the extraction and stripping capability as well as the separation effect of Nd^3＋ or Sm^3＋, from a sulfuric acid medium, by mixtures of di-（2-ethylhexyl） phosphoric acid （HDEHP, H2A2（0）） and 2-ethylhexyl phosphoric acid mono-2-ethylhexyl ester （HEH/EHP, H2L2（0）） were studied. The distribution ratios and synergistic coefficients of Nd^3＋ and Sm^3＋ in different acidities were also determined. A synergistic extractive effect was found when HDEHP and HEH/EHP were used as mixed extractants for Sm^3＋ or Nd^3＋. The chemical compositions of the extracted complex were determined as Nd.（HA2）2-HL2 and Sm.（HA2）2-HL2. The extraction equilibrium constants, enthalpy change, and entropy change of the extraction reaction were also determined.The extraction of Nd^3＋ and Sm^3＋, including the extraction and stripping capability as well as the separation effect of Nd^3＋ or Sm^3＋, from a sulfuric acid medium, by mixtures of di-（2-ethylhexyl） phosphoric acid （HDEHP, H2A2（0）） and 2-ethylhexyl phosphoric acid mono-2-ethylhexyl ester （HEH/EHP, H2L2（0）） were studied. The distribution ratios and synergistic coefficients of Nd^3＋ and Sm^3＋ in different acidities were also determined. A synergistic extractive effect was found when HDEHP and HEH/EHP were used as mixed extractants for Sm^3＋ or Nd^3＋. The chemical compositions of the extracted complex were determined as Nd.（HA2）2-HL2 and Sm.（HA2）2-HL2. The extraction equilibrium constants, enthalpy change, and entropy change of the extraction reaction were also determined.

关 键 词：di-（2-ethylhexyl） phosphoric acid 2-ethylhexyl phosphoric acid mono-2-ethylhexyl ester synergistic extraction mechanism  Sm^3＋  Nd^3＋ rare earths 

分 类 号：TG146.45[一般工业技术—材料科学与工程]