Selective removal of silver(i) using polymer inclusion membranes containing calixpyrroles

This paper discusses the results of studies on the transport of Ag(i) across polymer inclusion membranes (PIMs), derivatives of calixpyrroles with methyl (KP1) and carboxyl (KP2) groups, as ion carriers, o-nitrophenyl pentyl ether (o-NPPE) as a plasticizer and cellulose triacetate (CTA) as support. The influence of the pH of the source phase, metal concentration, stripping phase as well as carrier and plasticizer concentration on the efficiency of Ag(i) transport through PIM is presented. Long-term experiments with a supported liquid membrane and a plasticizer membrane demonstrate the durability of the studied PIMs. The obtained results indicate that the competitive transport of Cu(ii), Zn(ii), Ag(i) and Cd(ii) from the aqueous nitrate source phase through KP1 and KP2 is an effective separation method for Ag(i) ions. The prepared PIMs were characterized by scanning electron microscopy (SEM), and atomic force microscopy (AFM) techniques.