H_2A与TBP协同萃取RE(Ⅲ)的性能和机理研究

Synergistic Extraction of RE(Ⅲ) with H_2A and TBP

研究了 1,2 双 (1′ 苯基 3′ 甲基 5′ 氧代吡唑 4′ 基 )乙二酮 [1,2 ](H2 A)与磷酸三丁酯 (TBP)协同萃取RE(Ⅲ ) (RE =La、Pr、Nd、Gd、Dy和Y)的性能。通过考察萃取剂浓度和溶液酸度对RE(Ⅲ )萃取平衡的影响 ,确定了萃取机理和萃合物组成 ,求得了半萃取值pH1/ 2 和萃取反应平衡常数Ks.e .。

The synergistic extraction properties and mechanism of RE(Ⅲ)(RE=La,Pr,Nd,Y,Gd and Dy) with 1,2 bis(1′ phenyl 3′ methyl 5′ pyrazolone 4′ yl) ethanedione [1,2] (H 2A) and tributyl phosphate(TBP) were studied in nitric acid solution at 30±1℃. The results show that there is a notable synergistic effect on La 3+ for H 2A+TBP system,and the synergistic extraction coefficient of La 3+ is calculated to be 5.2. By investigating the influence of concentrations of H 2A and TBP on the extraction of La 3+ , the composition of extracted compound is determined as LaA·HA·TBP. The half extraction values pH 1/2 of La 3+ ,Pr 3+ ,Nd 3+ ,Gd 3+ ,Dy 3+ and Y 3+ are 4.19, 3.73,3.56,3.31,3.23 and 3.08, respectively. Meanwhile, the extraction equilibrium constants are also calculated.