Ionic Equilibria of Pt(IV), Pd(II) and Rh(III) in Hydrochloric Acid Solution

염산용액(鹽酸溶液)에서 白金(IV), 팔라듐(II)과 로듐(III)의 이온평형(平衡)

  • Lee, Man-Seung (Department of Advanced Materials Science & Engineering, Mokpo National University) ;
  • Lee, Jin-Young (Mineral Resources Research Division, Korea Institute of Geoscience and Mineral Resources)
  • 이만승 (목포대학교 공과대학 신소재공학과) ;
  • 이진영 (한국지질자원연구원 광물자원연구본부)
  • Published : 2009.02.27

Abstract

Distribution diagram of Pt(IV), Pd(II), and Rh(III) in HCl solution was obtained as a function of HCl concentration from 0.001 to 10 M by considering complex formation reaction together with mass balance. When HCl concentration was higher than 0.1 M, most of Pt and Pd in HCl solution exist as $PtCl_6^{2-}$ and $PtCl_4^{2-}$. The concentration of HCl had a feat effect on the speciation of Rh(III). As HCl concentration increases from 0.1 to 10 M, the pedominant species changes from $PhCl_5^{2-}$ to $PhCl_6^{3-}$. Interaction parameters of $PtCl_6^{2-}$ and $PdCl_4^{2-}$ with hydrogen ion were evaluated from the solvent extraction data of Pt and Pd reported in the literature.

염산농도 0.001에서 10 M사이의 범위에서 백금(IV)과 팔라듐(II) 및 로듐(III)의 착물형성반응과 물질수지를 고려하여 각 금속의 분배곡선을 구했다. 염산농도가 0.1 M이상인 조건에서는 백금과 팔라듐의 대부분은 $PtCl_6^{2-}$$PdCl_2^{2-}$로 존재하였다. 로듐의 농도분포는 염산농도에 큰 영향을 받는다. 염산농도가 0.1에서 10 M로 증가함에 따라 로듐의 주 화학종이 $PhCl_5^{2-}$에서 $PhCl_6^{3-}$로 변했다. 문헌에 발표된 백금과 팔라듐의 용매추출자료로부터 $PtCl_6^{2-}$$PtCl_4^{2-}$와 수소이온간의 매개변수를 추산했다.

Keywords

References

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