Various metal extraction from hydrochloric acid into n-dodecane by methylimino-dioctylacetamide (MIDOA)

ABSTRACT

Methylimino-di-n-octylacetamide (MIDOA) was used to extract 57 metals from HCl into n-dodecane. MIDOA is a tridentate ligand with one N donor and two carbonyl O donors and can extract soft acid metals and metal oxonium anions. In the present work, Fe(III), Zr(IV), Ga(III), Mo(VI), Tc(VII), Pd(II), Cd(II), In(III), Sn(IV), W(VI), Re(VII), Os(III), Ir(III), Pt(IV), Au(III), Hg(II), Bi(III), and U(VI) had distribution ratios above 10 when using 0.1 M MIDOA/n-dodecane and 3 M HCl. The amount of metal ion (Mo(VI), Tc(VII), Re(VII), Pd(II), Pt(IV), and Au(III)) extracted from HCl was greater than that obtained using HNO₃.

KEYWORDS:

• HCl
• MIDOA
• solvent extraction
• precious metal

Acknowledgments

I would like to acknowledge Associate Professor Masahiko Matsumiya, Yokohama National University, for his useful comments.