Anodic exchange reactions of extracted metal chelates with 1-pyrrolidinecarbodithioic acid in isobutyl methyl ketone.

Abstract

The metal-1-pyrrolidinecarbodithioate M(pcd)m, M=Mn(III), Fe(III), Co(III), Ni(II), Cu(II), Zn(II), In(III), Sb(III), Tl(I), Pb(II), and Bi(III), extracted from tartrate into isobutyl methyl ketone (IBMK, 4-methyl-2-pentanone), gives reduction and oxidation waves. The oxidation process is the anodic exchange reactions of the type (2/m)M(pcd)m + Hg_??_Hg(pcd)2 + (2/m)Mm+ + 2e-that can be studied electrochemically with Nernstian treatments. The formation constants of M(pcd)m in IBMK were calculated from the half-wave potentials of the anodic exchange reactions at a dropping mercury electrode. The adsorption pre-wave was observed in the oxidation wave for Zn(pcd)2 and the surface excess was calculated.