Activated composite membranes (ACMs) containing di-(2-ethylhexyl) dithiophosphoric acid (D2EHDTPA) as a carrier have been found to facilitate the transport and separation of several cations. This paper describes an approach to the chemical characterisation of the transport phenomena of Zn2+, Cd2+, Cu2+, Ni2+, Sn2+ and In 3+ by an ACM. The selectivity of D2EHDTPA based ACM towards different metal ions is presented and discussed focusing in Zn2+ and Cd 2+ transport and recovery. Selectivity demonstrates that zinc ions are removable from mixtures due to the different extraction strength of D2EHDTPA. Such selectivity is based on the differences of the dynamic behaviour of the metal ions transport. In addition, a correlation of the chemical behaviour of those ACM systems with the corresponding solvent extraction systems has been found. © 2004 Elsevier B.V. All rights reserved.
- Activated composite membranes
- Di-(2-ethylhexyl) dithiophosphoric acid
- Facilitated transport
- Mass transfer
- Metal ions