Liquid membrane transport of transition metal ions with calix[4] crowns

Selective transport of metal ions across liquid membrane can be achieved by using calixarene derivatives with recognition groups. Four new calix[4] cr owns, in this work, were examined for the transport of transition metal ion s such as Cu2+, Fe3+, Co2+, Ni2+ and Zn2+. It was found that one of these c alix crowns, 25 , 27-dihydroxy-26 , 28-(3' , 6' -dioxa-2' , 7' - dioxooctyl ene) dioxycalix [4] arene (III), transported efficiently Cu2+. Various fact ors affecting the transport Of Cu2+ with III were investigated in detail, i ncluding source phase and receiving phase' s acidities, carrier concentrati on, time, temperature, etc.. The mechanism of H+ exchange was suggested for the present system H3O- (liquid membrane)-H2O, and the transport process o f Cu2+ was briefly discussed.