Thermodynamic characterization of the liquid–liquid extraction of silver by acyclic dithia benzene derivatives Original Research Article

A study of the liquid–liquid extraction equilibria between aqueous Ag(I) and 1,3-bis[(ethylthio)methyl]benzene, 1,3-bis[(pentylthio)methyl]benzene and 1,3-bis[(octylthio)methyl]benzene in chloroform solution, is reported. The results have been expressed in terms of solvent extraction reactions between Ag(I) in aqueous solution and the ligands in the organic phase. A numerical analysis of the metal distribution data has determined the following reactions to be responsible for the extraction process in all cases:Ag++L(org)+NO−3→[LAg(NO3)](org)Ag++2L(org)+NO−3→[L2Ag(NO3)](org) From this analysis polynuclear species have also been found to be formed in the aqueous phase. Thus, trinuclear species [L3Ag3(NO3)3] were found to give the best interpretation of the experimental data.