Solvent Extraction Equilibria of Gd with PC88A from Chloride Solution

염산용액에서 PC88A에 의한 Gd 용매추출의 평형

  • 이광섭 (목포대학교 신소재공학과) ;
  • 이진영 (한국지질자원연구원 자원활용소재연구부) ;
  • 김성돈 (한국지질자원연구원 자원활용소재연구부) ;
  • 김전수 (한국지질자원연구원 자원활용소재연구부) ;
  • 박장현 (목포대학교 제어시스템공학과) ;
  • 이만승 (목포대학교 신소재공학과)
  • Published : 2004.04.01

Abstract

Solvent extraction equilibria of Gd with PC88A from chloride solutions were analyzed by considering chemical equilibria. phase equilibria, mass and charge balance equations. The following solvent extraction reaction and equilibrium constant were evaluated from the experimental data performed in this study. $Gd^{3+}$ $+2H_2$$A_2$,$or=GdA_3$HA.or+3 $H^{+}$ , K=3.3 A procedure was suggested to calculate the initial concentration of chloride ion from initial pH and initial concentration of Gd. By applying ionic equilibria, the distribution of Gd complexes with Gd and HCl concentration was obtained. The predicted distribution coefficients of Gd agreed well with the experimental results.

염산용액에서 PC88A에 의한 Gd추출반응의 평형을 해석하기 위해 화학반응, 상평형, 물질수지 및 전기적중성식을 고려하였다. 본 연구의 실험조건에서 PC88A에 의한 Gd의 추출반응에 대해 다음의 반응식과 평형상수를 얻었다. $Gd^{3+}$ $+2H_2$$A_2$,$or=GdA_3$HA.or+3$ H^{+/}$ , K=3.3 Gd의 초기농도와 pH로부터 염소의 초기농도를 구하는 방법을 제시했고, Gd과 염산농도에 따른 Gd 착물의 농도분포를 구했다. 본 연구에서 구한 Gd 추출반응의 평형상수와 이온평형을 초기 추출조건에 적용하여 예측한 Gd의 분배계수와 측정값은 서로 잘 일치하였다.

Keywords

References

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