Studies on Solvent Extraction and Analytical Application of Metal Dithiocarbamate Complexes(II). Extraction Equilibria of Metal-Dibenzylammonium dibenzyldithiocarbamate Complexes

Dithiocarbamate 금속착물의 용매추출 및 분석적 응용(제2보) Dibenzylammonium dibenzyldithiocarbamate 금속착물의 추출평형

  • Received : 1996.03.15
  • Published : 1996.09.25

Abstract

Basic studies for the effective extraction of dibenzylammonium dibenzyldithiocarbamate(DBADBDC) complexes of Ag(I), Pd(II), Au(III) and Pt(IV) into chloroform have been conducted. The effects of pH on the extraction of ligand itself and metal cemplexes showed that DBADBDC itself was uniformly extracted in the pH range of 2~9 and metal complexes were effectively extracted at the pH range as follows. That is, Ag(I) : in an acidic aqua medium, Pd(II) : > 4, Au(III) : wide range, and Pt(IV) : > 3. The distribution ratio and extractabilities were obtained from the partition and extraction equilibria of metal-DBDC complexes between aqueous solution and chloroform. Ag(I) : log D=4.226 : E(%)=99.9% in the aqueous solution of pH 0, Pd(II) : log D=1.804 : E(%)=98.5% at pH 4~7, Au(III) : log D=3.755 : E(%)=99.9% at pH 2~10, and Pt(IV) : log D=0.165 : E(%)=57.2% at pH 8.0. And also mole ratio of metal ion to ligand in complexes were determined by mole ratio method : 1 : 1 for Ag(I) and 1 : 2 for Pd(II), Au(III) and Pt(IV). $Cl^-$ was included as a coordination species in complexes of Au(III) and Pt(IV). Besides, extraction mechanisms of compleses sere examined in the presence of chloride ion in an aquous solution, and extraction reactions and estraction constants could be proposed and calculated, respectively.

Keywords

Dibenzylammonium dibenzyldithiocarbamate(DBADBDC);Extraction;Distribution ratio;Extraction constant;Noble metal ion

Acknowledgement

Supported by : 교육부 기초과학연구소